98 results on '"Masafumi Fukuto"'
Search Results
2. Machine-learning for designing nanoarchitectured materials by dealloying
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Chonghang Zhao, Cheng-Chu Chung, Siying Jiang, Marcus M. Noack, Jiun-Han Chen, Kedar Manandhar, Joshua Lynch, Hui Zhong, Wei Zhu, Phillip Maffettone, Daniel Olds, Masafumi Fukuto, Ichiro Takeuchi, Sanjit Ghose, Thomas Caswell, Kevin G. Yager, and Yu-chen Karen Chen-Wiegart
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Materials of engineering and construction. Mechanics of materials ,TA401-492 - Abstract
Nanoporous metals produced by metal agent dealloying are attractive for multiple applications. Here, a machine learning-augmented framework is reported for predicting, synthesizing and characterizing ternary systems for dealloying.
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- 2022
- Full Text
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3. Enhanced piezoelectricity from highly polarizable oriented amorphous fractions in biaxially oriented poly(vinylidene fluoride) with pure β crystals
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Yanfei Huang, Guanchun Rui, Qiong Li, Elshad Allahyarov, Ruipeng Li, Masafumi Fukuto, Gan-Ji Zhong, Jia-Zhuang Xu, Zhong-Ming Li, Philip L. Taylor, and Lei Zhu
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Science - Abstract
Piezoelectric polymers usually have rather low piezoelectric coefficients less than 30 pC/N. Here, the authors achieve a highly piezoelectric polymer (d 33 = −62 pC/N) based on a poled biaxially oriented poly(vinylidene fluoride) with a pure β phase due to the mobile oriented amorphous fraction.
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- 2021
- Full Text
- View/download PDF
4. Smectic-B phase and temperature-driven smectic-B to -A transition in concentrated solutions of 'gapped' DNA
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Prabesh Gyawali, Rony Saha, Sineth G. Kodikara, Ruipeng Li, Masafumi Fukuto, James T. Gleeson, Gregory P. Smith, Noel A. Clark, Antal Jakli, Hamza Balci, and Samuel Sprunt
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Physics ,QC1-999 - Abstract
The occurrence of a smectic-B (Sm-B) phase is demonstrated in concentrated aqueous solutions of “gapped” DNA constructs consisting of fully paired duplexes bridged by a flexible, unpaired strand of nucleotides. The Sm-B phase, identified by small and wide angle x-ray scattering measurements and optical microscopy, develops from a smectic-A (Sm-A) phase with increasing DNA concentration at room temperature. It transitions (reversibly) to the Sm-A when the temperature is raised above ∼50^{∘}C.
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- 2022
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5. Liquid crystal phases with unusual structures and physical properties formed by acute-angle bent core molecules
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Bing-Xiang Li, Yuriy A. Nastishin, Hao Wang, Min Gao, Sathyanarayana Paladugu, Ruipeng Li, Masafumi Fukuto, Quan Li, Sergij V. Shiyanovskii, and Oleg D. Lavrentovich
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Physics ,QC1-999 - Abstract
Liquid crystals formed by acute-angle bent core (ABC) molecules with a 1,7 naphthalene central core show an intriguing phase behavior with the nematic phase accompanied by poorly understood additional phases. In this work, we characterize the physical properties of an ABC material, such as birefringence, dielectric permittivities, elastic constants, and surface alignment and present x-ray diffraction and transmission electron microscopy studies of their ordering. The ABC molecular shape resembling the letter λ yields a very small splay elastic constant in the uniaxial nematic phase and results in the formation of a tetragonal positionally ordered columnar phase consisting of alternating polar and apolar molecular columns with a uniform uniaxial director that can be bent but not splayed.
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- 2020
- Full Text
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6. Influence of the Nature of Aliphatic Hydrophobic Physical Crosslinks on Water Crystallization in Copolymer Hydrogels
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Pablo I. Sepulveda-Medina, Chao Wang, Ruipeng Li, Masafumi Fukuto, and Bryan D. Vogt
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Acrylates ,Polymers ,Ice ,Materials Chemistry ,Water ,Hydrogels ,Physical and Theoretical Chemistry ,Crystallization ,Surfaces, Coatings and Films - Abstract
The local environment within a hydrogel influences the properties of water, including the propensity for ice crystallization. Water-swollen amphiphilic copolymers produce tunable nanoscale environments, which are defined by hydrophobic associations, for the water molecules. Here, the antifreeze properties for equilibrium-swollen amphiphilic copolymers with a common hydrophilic component, hydroxyethyl acrylate (HEA), but associated through crystalline (octadecyl acrylate, ODA) or rubbery (ethylhexyl acrylate, EHA) hydrophobic segments, are examined. Differences in the efficacy of the associations can be clearly enunciated from compositional solubility limits for the copolymers in water (2.6 mol % ODA vs ≤14 mol % EHA), and these differences can be attributed to the strength of the association. The equilibrium-swollen HEA-ODA copolymers are viscoelastic solids, while the swollen HEA-EHA copolymers are viscoelastic liquids. Cooling these swollen copolymers to nearly 200 K induces some crystallization of the water, where the fraction of water frozen depends on the details of the nanostructure. Decreasing the mean free path of water by increasing the ODA composition from 10 to 25 mol % leads to fractionally more unfrozen water (66-87%). The swollen HEA-EHA copolymers only marginally inhibit ice (13%) except with 45 mol % EHA, where nearly 60% of the water remains amorphous on cooling to 200 K. In general, the addition of the EHA leads to less effective ice inhibition than analogous covalently crosslinked HEA hydrogels (19.9 ± 1.8%). These results illustrate that fluidity of confining surfaces can provide pathways for critical nuclei to form and crystal growth to proceed.
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- 2022
7. Advancing Discovery with Artificial Intelligence and Machine Learning at NSLS-II
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Andi Barbour, Stuart Campbell, Thomas Caswell, Masafumi Fukuto, Marcus Hanwell, Andrew Kiss, Tatiana Konstantinova, Ricarda Laasch, Phillip Maffettone, Bruce Ravel, and Daniel Olds
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Nuclear and High Energy Physics ,Atomic and Molecular Physics, and Optics - Published
- 2022
8. Multiple ferroelectric nematic phases of a highly polar liquid crystal compound
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Rony Saha, Pawan Nepal, Chenrun Feng, Md Sakhawat Hossain, Masafumi Fukuto, Ruipeng Li, James T. Gleeson, Samuel Sprunt, Robert J. Twieg, and Antal Jákli
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General Materials Science ,General Chemistry ,Condensed Matter Physics - Published
- 2022
9. Autonomous discovery of emergent morphologies in directed self-assembly of block copolymer blends
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Gregory S. Doerk, Aaron Stein, Suwon Bae, Marcus M. Noack, Masafumi Fukuto, and Kevin G. Yager
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Multidisciplinary - Abstract
The directed self-assembly (DSA) of block copolymers (BCPs) is a powerful approach to fabricate complex nanostructure arrays, but finding morphologies that emerge with changes in polymer architecture, composition, or assembly constraints remains daunting because of the increased dimensionality of the DSA design space. Here, we demonstrate machine-guided discovery of emergent morphologies from a cylinder/lamellae BCP blend directed by a chemical grating template, conducted without direct human intervention on a synchrotron x-ray scattering beamline. This approach maps the morphology-template phase space in a fraction of the time required by manual characterization and highlights regions deserving more detailed investigation. These studies reveal localized, template-directed partitioning of coexisting lamella- and cylinder-like subdomains at the template period length scale, manifesting as previously unknown morphologies such as aligned alternating subdomains, bilayers, or a “ladder” morphology. This work underscores the pivotal role that autonomous characterization can play in advancing the paradigm of DSA.
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- 2023
10. Grazing-incidence X-ray diffraction tomography for characterizing organic thin films
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Esther H. R. Tsai, Yueh-Lin Loo, Ruipeng Li, Masafumi Fukuto, and Yu Xia
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Materials science ,Astrophysics::High Energy Astrophysical Phenomena ,02 engineering and technology ,tomography ,010402 general chemistry ,01 natural sciences ,General Biochemistry, Genetics and Molecular Biology ,law.invention ,Diffraction tomography ,Optics ,law ,Thin film ,GIWAXS ,Scattering ,business.industry ,grazing-incidence wide-angle X-ray scattering ,021001 nanoscience & nanotechnology ,Research Papers ,organic transistors ,Synchrotron ,0104 chemical sciences ,Characterization (materials science) ,thin films ,X-ray crystallography ,Physics::Accelerator Physics ,Tomography ,0210 nano-technology ,business ,Coherence (physics) - Abstract
A computational method that directly translates the scattering peak information to crystalline domain shapes and orientations is presented. The method is demonstrated at a synchrotron beamline with a standard X-ray scattering setup., Characterization of thin films is of paramount importance for evaluating material processing outcomes/efficiency as well as establishing structure–property/performance relationships. This article introduces grazing-incidence diffraction tomography (GID tomography), a technique that combines grazing-incidence X-ray scattering and computed tomography to quantitatively determine the dimension and orientation of crystalline domains in thin films without restrictions on the beam coherence, substrate type or film thickness. This computational method extends the capability of synchrotron beamlines by utilizing standard X-ray scattering experiment setups.
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- 2021
11. Gaussian processes for autonomous data acquisition at large-scale synchrotron and neutron facilities
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Petrus H. Zwart, Paolo Mutti, Daniela M. Ushizima, Steven B. Lee, Katherine C. Elbert, Tobias Weber, Masafumi Fukuto, Aaron Stein, James A. Sethian, Gregory S. Doerk, Paul Steffens, Yannick Le Goc, Martin Boehm, Marcus M. Noack, Esther H. R. Tsai, Ruipeng Li, Eli Rotenberg, Christopher B. Murray, Guillaume Freychet, Kevin G. Yager, Mikhail Zhernenkov, Hoi-Ying N. Holman, and Liang Chen
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Computer science ,General Physics and Astronomy ,computer.software_genre ,symbols.namesake ,Function approximation ,Data acquisition ,Kriging ,Ground-penetrating radar ,symbols ,Use case ,Data mining ,Uncertainty quantification ,computer ,Gaussian process ,Curse of dimensionality - Abstract
The execution and analysis of complex experiments are challenged by the vast dimensionality of the underlying parameter spaces. Although an increase in data-acquisition rates should allow broader querying of the parameter space, the complexity of experiments and the subtle dependence of the model function on input parameters remains daunting owing to the sheer number of variables. New strategies for autonomous data acquisition are being developed, with one promising direction being the use of Gaussian process regression (GPR). GPR is a quick, non-parametric and robust approximation and uncertainty quantification method that can be applied directly to autonomous data acquisition. We review GPR-driven autonomous experimentation and illustrate its functionality using real-world examples from large experimental facilities in the USA and France. We introduce the basics of a GPR-driven autonomous loop with a focus on Gaussian processes, and then shift the focus to the infrastructure that needs to be built around GPR to create a closed loop. Finally, the case studies we discuss show that Gaussian-process-based autonomous data acquisition is a widely applicable method that can facilitate the optimal use of instruments and facilities by enabling the efficient acquisition of high-value datasets. Gaussian process regression (GPR) is a powerful, non-parametric and robust technique for uncertainty quantification and function approximation that can be applied to optimal and autonomous data acquisition. This Review introduces the basics of GPR and discusses several use cases from different fields.
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- 2021
12. Autonomous x-ray scattering
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Kevin G Yager, Pawel W Majewski, Marcus M Noack, and Masafumi Fukuto
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Mechanics of Materials ,Mechanical Engineering ,General Materials Science ,Bioengineering ,General Chemistry ,Electrical and Electronic Engineering - Abstract
Autonomous experimentation (AE) is an emerging paradigm that seeks to automate the entire workflow of an experiment, including—crucially—the decision-making step. Beyond mere automation and efficiency, AE aims to liberate scientists to tackle more challenging and complex problems. We describe our recent progress in the application of this concept at synchrotron x-ray scattering beamlines. We automate the measurement instrument, data analysis, and decision-making, and couple them into an autonomous loop. We exploit Gaussian process modeling to compute a surrogate model and associated uncertainty for the experimental problem, and define an objective function exploiting these. We provide example applications of AE to x-ray scattering, including imaging of samples, exploration of physical spaces through combinatorial methods, and coupling to in situ processing platforms These uses demonstrate how autonomous x-ray scattering can enhance efficiency, and discover new materials.
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- 2023
13. Laponite-Incorporated UiO-66-NH2-Polyethylene Oxide Composite Membranes for Protection against Chemical Warfare Agent Simulants
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Matthew A. Browe, John Landers, Trenton M. Tovar, John J. Mahle, Alex Balboa, Wesley O. Gordon, Masafumi Fukuto, and Christopher J. Karwacki
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General Materials Science - Published
- 2021
14. Kinetics and evolution of solid-state metal dealloying in thin films with multimodal analysis
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Chonghang Zhao, Lin-Chieh Yu, Kim Kisslinger, Charles Clark, Cheng-Chu Chung, Ruipeng Li, Masafumi Fukuto, Ming Lu, Jianming Bai, Xiaoyang Liu, Hui Zhong, Mingzhao Liu, Sanjit Ghose, and Yu-chen Karen Chen-Wiegart
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Polymers and Plastics ,Metals and Alloys ,Ceramics and Composites ,Electronic, Optical and Magnetic Materials - Published
- 2023
15. Ultrastructure of Critical-Gel-like Polyzwitterion–Polyoxometalate Complex Coacervates: Effects of Temperature, Salt Concentration, and Shear
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Jie Qiu, Masafumi Fukuto, Manuela Ferreira, Benxin Jing, Yingxi Zhu, Kehua Lin, Ruipeng Li, and Benjamin M. Yavitt
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Inorganic Chemistry ,Shear (sheet metal) ,chemistry.chemical_classification ,Coacervate ,Polymers and Plastics ,Chemical engineering ,Chemistry ,Organic Chemistry ,Polyoxometalate ,Materials Chemistry ,Ultrastructure ,Salt (chemistry) - Abstract
The structure of unconventional complex coacervates, such as polymer–nonpolymer complex coacervates, remains less investigated than that of the conventional coacervates formed between oppositely ch...
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- 2020
16. Autonomous materials discovery driven by Gaussian process regression with inhomogeneous measurement noise and anisotropic kernels
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Marcus M. Noack, Jason K. Streit, Richard A. Vaia, Kevin G. Yager, Gregory S. Doerk, Ruipeng Li, and Masafumi Fukuto
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0301 basic medicine ,FOS: Computer and information sciences ,Process (engineering) ,Mathematics and computing ,Energy science and technology ,FOS: Physical sciences ,lcsh:Medicine ,Machine Learning (stat.ML) ,02 engineering and technology ,Machine learning ,computer.software_genre ,Article ,03 medical and health sciences ,Engineering ,Kriging ,Statistics - Machine Learning ,lcsh:Science ,Multidisciplinary ,business.industry ,Physics ,lcsh:R ,Computational Physics (physics.comp-ph) ,021001 nanoscience & nanotechnology ,Materials science ,Variety (cybernetics) ,Noise ,Chemistry ,030104 developmental biology ,Face (geometry) ,Ground-penetrating radar ,lcsh:Q ,Artificial intelligence ,0210 nano-technology ,Focus (optics) ,business ,computer ,Physics - Computational Physics - Abstract
A majority of experimental disciplines face the challenge of exploring large and high-dimensional parameter spaces in search of new scientific discoveries. Materials science is no exception; the wide variety of synthesis, processing, and environmental conditions that influence material properties gives rise to particularly vast parameter spaces. Recent advances have led to an increase in the efficiency of materials discovery by increasingly automating the exploration processes. Methods for autonomous experimentation have become more sophisticated recently, allowing for multi-dimensional parameter spaces to be explored efficiently and with minimal human intervention, thereby liberating the scientists to focus on interpretations and big-picture decisions. Gaussian process regression (GPR) techniques have emerged as the method of choice for steering many classes of experiments. We have recently demonstrated the positive impact of GPR-driven decision-making algorithms on autonomously-steered experiments at a synchrotron beamline. However, due to the complexity of the experiments, GPR often cannot be used in its most basic form, but rather has to be tuned to account for the special requirements of the experiments. Two requirements seem to be of particular importance, namely inhomogeneous measurement noise (input-dependent or non-i.i.d.) and anisotropic kernel functions, which are the two concepts that we tackle in this paper. Our synthetic and experimental tests demonstrate the importance of both concepts for experiments in materials science and the benefits that result from including them in the autonomous decision-making process.
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- 2020
17. Cyclic Topology Enhancing Structural Ordering and Stability of Comb-Shaped Polypeptoid Thin Films against Melt-Induced Dewetting
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Ying Wu, Liying Kang, Donghui Zhang, Naisheng Jiang, Jianxia Chen, Kangmin Niu, Albert Chao, Masafumi Fukuto, Tianyi Yu, and Ruipeng Li
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Materials science ,Polymers and Plastics ,Silicon ,fungi ,Organic Chemistry ,chemistry.chemical_element ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Topology ,01 natural sciences ,Stability (probability) ,Article ,0104 chemical sciences ,Inorganic Chemistry ,Chain (algebraic topology) ,chemistry ,Mathematics::K-Theory and Homology ,Materials Chemistry ,Thermal stability ,Dewetting ,Thin film ,0210 nano-technology ,Topology (chemistry) - Abstract
We investigated the effect of cyclic chain topology on the molecular ordering and thermal stability of comb-shaped polypeptoid thin films on silicon (Si) substrates. Cyclic and linear poly(N-decylglycine) (PNDG) bearing long n-decyl side chains were synthesized by ring-opening polymerization of N-decylglycine-derived N-carboxyanhydrides. When the spin-coated thin films were subjected to thermal annealing at temperatures above the melting temperature (T > Tm), the cyclic PNDG films exhibited significantly enhanced stability against melt-induced dewetting than the linear counterparts (l-PNDG). When recrystallized at temperatures below the crystallization temperature (T < Tc), the homogeneous c-PNDG films exhibit enhanced crystalline ordering relative to the macroscopically dewetted l-PNDG films. Both cyclic and linear PNDG molecules adopt cis-amide conformations in the crystalline film, which transition into trans-amide conformations upon melting. A top-down solvent leaching treatment of both l/c-PNDG films revealed the formation of an irreversibly physisorbed monolayer with similar thickness (ca. 3 nm) on the Si substrate. The physisorbed monolayers are more disordered relative to the respective thicker crystalline films for both cyclic and linear PNDGs. Upon heating above Tm, the adsorbed c-PNDG chains adopt trans-amide backbone conformation identical with the free c-PNDG molecules in the molten film. By contrast, the backbone conformations of l-PNDG chains in the adsorbed layers are notably different from those of the free chains in the molten film. We postulate that the conformational disparity between the chains in the physically adsorbed layers versus the free chains in the molten film is an important factor to account for the difference in the thermal stability of PNDG thin films. These findings highlight the use of cyclic chain topology to suppress the melt-induced dewetting in polymer thin films.
- Published
- 2020
18. Long-Range Lamellar Alignment in Diblock Bottlebrush Copolymers via Controlled Oscillatory Shear
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Benjamin M. Yavitt, H. Henning Winter, James J. Watkins, Huafeng Fei, Masafumi Fukuto, Ruipeng Li, and Gayathri Kopanati
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Inorganic Chemistry ,Range (particle radiation) ,Oscillatory shear ,Materials science ,Nanostructure ,Polymers and Plastics ,Chemical physics ,Organic Chemistry ,Materials Chemistry ,Copolymer ,Lamellar structure - Abstract
A simple strategy is presented to achieve well-ordered nanostructures in microphase-separated diblock bottlebrush copolymers (dbBB) for potential opportunities in nanotechnology that require large ...
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- 2020
19. Wet Brush Homopolymers as 'Smart Solvents' for Rapid, Large Period Block Copolymer Thin Film Self-Assembly
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Ruipeng Li, Gregory S. Doerk, Kevin G. Yager, and Masafumi Fukuto
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Materials science ,Polymers and Plastics ,Annealing (metallurgy) ,Organic Chemistry ,Plasticizer ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Inorganic Chemistry ,Solvent ,chemistry.chemical_compound ,Chemical engineering ,chemistry ,Materials Chemistry ,Copolymer ,Self-assembly ,Polystyrene ,Methyl methacrylate ,Thin film ,0210 nano-technology - Abstract
The spontaneous formation of periodic nanopatterns through the self-assembly of block copolymer (BCP) thin films offers an enticing path to engineer functional material properties over large areas, but the prohibitively slow ordering of ultrahigh molecular weight BCPs that generate large pattern periods (>100 nm) severely restricts the design space in which BCPs may be used. Here, we demonstrate that blending lamellae-forming polystyrene-block-poly(methyl methacrylate) diblock copolymers with very low molecular weight polystyrene and poly(methyl methacrylate) homopolymers can reduce by an order-of-magnitude the times required to form ordered large period patterns through solvent vapor annealing. Using in situ grazing-incidence small-angle X-ray scattering and ex situ electron microscopy, we show that the added homopolymer plasticizers act as a “smart solvent”: They increase the mobility of the long BCP chains by amplifying the dilution effect during solvent vapor annealing but segregate to like domains du...
- Published
- 2020
20. Ordered three-dimensional nanomaterials using DNA-prescribed and valence-controlled material voxels
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Lin Bai, Yan Xiong, Jason S. Kahn, Masafumi Fukuto, Oleg Gang, Huolin L. Xin, Ruipeng Li, Thi Vo, Huilin Li, Kevin G. Yager, Brian Minevich, Sanat K. Kumar, Julien Lhermitte, and Ye Tian
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chemistry.chemical_classification ,Valence (chemistry) ,Materials science ,Fabrication ,Mechanical Engineering ,Biomolecule ,Nanoparticle ,Nanotechnology ,02 engineering and technology ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,computer.software_genre ,01 natural sciences ,0104 chemical sciences ,Nanomaterials ,chemistry ,Mechanics of Materials ,Voxel ,General Materials Science ,0210 nano-technology ,Nanoscopic scale ,computer ,Spectral purity - Abstract
The ability to organize nanoscale objects into well-defined three-dimensional (3D) arrays can translate advances in nanoscale synthesis into targeted material fabrication. Despite successes in nanoparticle assembly, most extant methods are system specific and not fully compatible with biomolecules. Here, we report a platform for creating distinct 3D ordered arrays from different nanomaterials using DNA-prescribed and valence-controlled material voxels. These material voxels consist of 3D DNA frames that integrate nano-objects within their scaffold, thus enabling the object's valence and coordination to be determined by the frame's vertices, which can bind to each other through hybridization. Such DNA material voxels define the lattice symmetry through the spatially prescribed valence decoupling the 3D assembly process from the nature of the nanocomponents, such as their intrinsic properties and shapes. We show this by assembling metallic and semiconductor nanoparticles and also protein superlattices. We support the technological potential of such an assembly approach by fabricating light-emitting 3D arrays with diffraction-limited spectral purity and 3D enzymatic arrays with increased activity.
- Published
- 2020
21. Advances in Kriging-Based Autonomous X-Ray Scattering Experiments
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Marcus M. Noack, Kevin G. Yager, Ruipeng Li, Gregory S. Doerk, and Masafumi Fukuto
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Mathematics and computing ,Energy science and technology ,lcsh:Medicine ,Bioengineering ,02 engineering and technology ,010402 general chemistry ,computer.software_genre ,01 natural sciences ,Article ,Surrogate model ,Kriging ,Sensitivity (control systems) ,Variogram ,lcsh:Science ,Multidisciplinary ,Data collection ,lcsh:R ,Experimental data ,Variance (accounting) ,Function (mathematics) ,021001 nanoscience & nanotechnology ,Materials science ,0104 chemical sciences ,Other Physical Sciences ,Generic Health Relevance ,lcsh:Q ,Data mining ,Biochemistry and Cell Biology ,0210 nano-technology ,computer - Abstract
Autonomous experimentation is an emerging paradigm for scientific discovery, wherein measurement instruments are augmented with decision-making algorithms, allowing them to autonomously explore parameter spaces of interest. We have recently demonstrated a generalized approach to autonomous experimental control, based on generating a surrogate model to interpolate experimental data, and a corresponding uncertainty model, which are computed using a Gaussian process regression known as ordinary Kriging (OK). We demonstrated the successful application of this method to exploring materials science problems using x-ray scattering measurements at a synchrotron beamline. Here, we report several improvements to this methodology that overcome limitations of traditional Kriging methods. The variogram underlying OK is global and thus insensitive to local data variation. We augment the Kriging variance with model-based measures, for instance providing local sensitivity by including the gradient of the surrogate model. As with most statistical regression methods, OK minimizes the number of measurements required to achieve a particular model quality. However, in practice this may not be the most stringent experimental constraint; e.g. the goal may instead be to minimize experiment duration or material usage. We define an adaptive cost function, allowing the autonomous method to balance information gain against measured experimental cost. We provide synthetic and experimental demonstrations, validating that this improved algorithm yields more efficient autonomous data collection.
- Published
- 2020
22. 'Structurally Neutral' Densely Packed Homopolymer-Adsorbed Chains for Directed Self-Assembly of Block Copolymer Thin Films
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Ashwanth Subramanian, Naisheng Jiang, Keiji Tanaka, Mani Sen, Maya K. Endoh, Andrei Fluerasu, Shotaro Nishitsuji, Yugang Zhang, Chang-Yong Nam, Masafumi Fukuto, Benjamin M. Yavitt, Lutz Wiegart, Yuma Morimitsu, Tadanori Koga, Ruipeng Li, and Daniel Salatto
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chemistry.chemical_classification ,Materials science ,Polymers and Plastics ,Silicon ,Organic Chemistry ,chemistry.chemical_element ,02 engineering and technology ,Polymer ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Inorganic Chemistry ,chemistry.chemical_compound ,Dynamic light scattering ,chemistry ,Chemical engineering ,Materials Chemistry ,Copolymer ,Surface modification ,Lamellar structure ,Methyl methacrylate ,Thin film ,0210 nano-technology - Abstract
We here report that adsorbed chains composed of one of the constituent blocks can be used as a new surface modification approach to induce perpendicularly oriented lamellar microdomains in block copolymer thin films. A nearly symmetric polystyrene-block-poly(methyl methacrylate) (PS-block-PMMA) diblock copolymer was used as a model. Densely packed PS- or PMMA-adsorbed chains of about 2–3 nm in thickness (“polymer nanocoatings”) were deposited on silicon (Si) substrates using a solvent-rinsing approach. Spin-cast films of 40 or 60 nm-thick PS-block-PMMA (equivalent to two or three interdomain spacings) were subsequently deposited onto the PS or PMMA nanocoatings. Grazing incidence small-angle X-ray scattering experiments revealed the formation of perpendicularly oriented lamellar microdomains within the entire films at 200 °C, where balanced interfacial interactions at the polymer–air interface were achieved. Additionally, X-ray photon correlation spectroscopy studies demonstrated the dynamics of the fully...
- Published
- 2019
23. Linker-Mediated Assembly of Virus-Like Particles into Ordered Arrays via Electrostatic Control
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Byeongdu Lee, Lin Yang, Nicholas E. Brunk, Trevor Douglas, Vikram Jadhao, Masaki Uchida, and Masafumi Fukuto
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Biomaterials ,Biomimetic materials ,Chemistry ,viruses ,Protein subunit ,Biochemistry (medical) ,Biomedical Engineering ,Biophysics ,General Chemistry ,Self-assembly ,Kinetic control ,Linker ,Virus - Abstract
Nanoscale virus-like particles (VLPs), which are self-assembled from protein subunits, offer the possibility of generating hierarchically assembled functional materials such as biomimetic catalytic systems and optical metamaterials. We explore the capacity to control and tune a higher-order assembly of VLPs into ordered array materials over a wide range of ionic conditions using a combination of experimental and computational methods. The integrated methodology demonstrates that P22 VLP variants, genetically engineered to exhibit different surface charges, self-assemble into ordered arrays in the presence of PAMAM dendrimers acting as oppositely charged, macromolecular linkers. Ordered assembly occurs at an optimal ionic strength that strongly correlates with the VLP surface charge. The ordered VLP arrays exhibit the same long-range order and a similar configuration of VLP-bound dendrimers, regardless of the VLP surface charge. The experimentally validated model identifies key electrostatic and kinetic mechanisms underlying the self-assembly process and guides the modulation of dendrimer concentration as a control parameter to tune the assembly of VLPs. The integrated approach opens new design and control strategies to fabricate active functional materials via the self-assembly of engineered VLPs.
- Published
- 2019
24. High Dielectric Constant Polycarbonate/Nylon Multilayer Films Capacitors with Self-Healing Capability
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Deepak Langhe, Michael Ponting, Michael Brubaker, Terry Hosking, Masafumi Fukuto, Eric Baer, Ruipeng Li, Lei Zhu, Xinyue Chen, Zhenpeng Li, and Ci Zhang
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Materials science ,Polymers and Plastics ,business.industry ,Process Chemistry and Technology ,Organic Chemistry ,Dielectric ,law.invention ,Capacitor ,law ,visual_art ,Self-healing ,Power electronics ,visual_art.visual_art_medium ,Optoelectronics ,Field-effect transistor ,Polycarbonate ,Current (fluid) ,business ,High-κ dielectric - Abstract
With the fast development of high-temperature metal oxide semiconductor field effect transistors for power electronics in electric vehicles, current state-of-the-art biaxially oriented polypropylen...
- Published
- 2019
25. Molecular Structure of Aromatic Reverse Osmosis Polyamide Barrier Layers
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Benjamin S. Hsiao, Nisha Verma, Qinyi Fu, Masafumi Fukuto, Benjamin M. Ocko, Francisco J. Medellín-Rodríguez, Ruipeng Li, Hongyang Ma, and Christopher M. Stafford
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Materials science ,Polymers and Plastics ,Organic Chemistry ,02 engineering and technology ,Permeance ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Chloride ,Interfacial polymerization ,0104 chemical sciences ,Inorganic Chemistry ,Membrane ,Chemical engineering ,Polyamide ,Materials Chemistry ,Perpendicular ,medicine ,Molecule ,0210 nano-technology ,Reverse osmosis ,medicine.drug - Abstract
The molecular structures of polyamide barrier layers in reverse osmosis membranes, made by interfacial polymerization of m-phenylenediamine and trimesoyl chloride under different reaction and post-treatment conditions, were characterized by grazing incidence wide-angle X-ray scattering (GIWAXS). The molecular backbone packing is consistent with two different aromatic molecular packing motifs (parallel and perpendicular) with preferential surface-induced orientation. The results suggest that the perpendicular, T-shaped, packing motif (5 A spacing) might be associated with optimal membrane permeance, compared with the parallel packings (3.5–4.0 A spacings).
- Published
- 2019
26. Self-Organization of Triblock Copolymer Melt Chains Physisorbed on Non-neutral Surfaces
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Chang-Yong Nam, Xiaoyu Di, Maya K. Endoh, Tadanori Koga, Daniel Salatto, Masafumi Fukuto, and Naisheng Jiang
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Materials science ,Silicon ,Scattering ,General Chemical Engineering ,chemistry.chemical_element ,02 engineering and technology ,General Chemistry ,Substrate (electronics) ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Article ,0104 chemical sciences ,Adsorption ,Chemical engineering ,chemistry ,Ellipsometry ,Copolymer ,Thin film ,0210 nano-technology ,Glass transition - Abstract
We here report the self-organization process of poly(styrene-b-ethylene/butadiene-b-styrene) (SEBS) triblock copolymer chains physically adsorbed on a non-neutral surface. Spin-cast SEBS thin films were prepared on silicon (Si) substrates and then annealed at a high temperature far above the bulk glass transition temperatures of the two constituent blocks. To reveal the buried interfacial structure, we utilized solvent rinsing processes and a suite of surface-sensitive techniques including ellipsometry, X-ray reflectivity, atomic force microscopy, and grazing incidence small angle X-ray scattering. We revealed that the SEBS chains form two different chain structures on the substrate simultaneously: (i) “flattened chains” with the average height of 2.5 nm but without forming microdomain structures; (ii) “loosely adsorbed chains” with the average height of 11.0 nm and the formation of perpendicularly oriented cylindrical microdomains to the substrate surface. In addition, the kinetics to form the perpendicular-oriented cylinder was sluggish (∼200 h) and proceeded via multistep processes toward the equilibrium state. We also found that the lateral microdomain structures were distorted, and the characteristic lengths of the microdomains were slightly different from the bulk even after reaching “quasiequilibrium” state within the observed time window. Furthermore, we highlight the vital role of the adsorbed chains in the self-assembling process of the entire SEBS thin film: a long-range perturbation associated with the adsorbed chains propagates into the film interior, overwhelming the free surface effect associated with surface segregation of the lower surface tension of polystyrene blocks.
- Published
- 2018
27. Antifreeze Hydrogels from Amphiphilic Statistical Copolymers
- Author
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Pablo I. Sepulveda-Medina, Changhuai Ye, Robert Weiss, David S. Simmons, Bryan D. Vogt, Clinton G. Wiener, Masafumi Fukuto, Chao Wang, and Ruipeng Li
- Subjects
Hydrogen bond ,Chemistry ,General Chemical Engineering ,02 engineering and technology ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Methacrylate ,01 natural sciences ,0104 chemical sciences ,law.invention ,Chemical engineering ,law ,Antifreeze ,Self-healing hydrogels ,Amphiphile ,Materials Chemistry ,Copolymer ,Crystallization ,0210 nano-technology ,Supercooling - Abstract
Prevention of ice formation is a critical issue for many applications, but routes to overcome the large thermodynamic driving force for crystallization of water at significant supercooling are limited. Here, we demonstrate that supramolecular hydrogels formed from statistical copolymers of 2-hydroxyethyl acrylate (HEA) and 2-(N-ethylperfluorooctane sulfonamido)ethyl methacrylate (FOSM) exhibit a degree of ice formation suppression unprecedented in a synthetic material. The mechanisms of ice prevention by these hydrogels mimic two methods used by nature: (1) hydrogen bonding of water to highly hydrophilic macromolecular chains and (2) nanoconfinement of water between hydrophobic moieties. From systematic variation in the copolymer composition to control the nanoscale (
- Published
- 2018
28. High Dielectric Constant Semiconducting Poly(3-alkylthiophene)s from Side Chain Modification with Polar Sulfinyl and Sulfonyl Groups
- Author
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Zhongbo Zhang, Ruipeng Li, Chunlai Wang, Lei Zhu, Sandra Pejić, Masafumi Fukuto, and Geneviève Sauvé
- Subjects
Sulfonyl ,chemistry.chemical_classification ,Materials science ,Polymers and Plastics ,Condensed Matter::Other ,Exciton ,Organic Chemistry ,02 engineering and technology ,Condensed Matter::Mesoscopic Systems and Quantum Hall Effect ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Photochemistry ,01 natural sciences ,0104 chemical sciences ,Inorganic Chemistry ,Organic semiconductor ,Condensed Matter::Materials Science ,chemistry ,Hardware_GENERAL ,Hardware_INTEGRATEDCIRCUITS ,Materials Chemistry ,Side chain ,Polar ,0210 nano-technology ,High-κ dielectric - Abstract
There is growing interest in designing and developing high dielectric constant (er) organic semiconductors because they have the potential to further enhance device performance by promoting exciton...
- Published
- 2018
29. Mono- and bilayer smectic liquid crystal ordering in dense solutions of 'gapped' DNA duplexes
- Author
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James T. Gleeson, Mirosław Salamończyk, Gregory P. Smith, Masafumi Fukuto, Soumitra Basu, Hamza Balci, Ruipeng Li, Prakash Kharel, Noel A. Clark, Rony Saha, Antal Jakli, Samuel Sprunt, and Prabesh Gyawali
- Subjects
Phase transition ,Multidisciplinary ,Materials science ,Molecular Structure ,Small-angle X-ray scattering ,Bilayer ,DNA ,Liquid Crystals ,Solutions ,Crystallography ,Liquid crystal ,Phase (matter) ,Physical Sciences ,Monolayer ,Molecule ,Lamellar structure - Abstract
Although its mesomorphic properties have been studied for many years, only recently has the molecule of life begun to reveal the true range of its rich liquid crystalline behavior. End-to-end interactions between concentrated, ultrashort DNA duplexes—driving the self-assembly of aggregates that organize into liquid crystal phases—and the incorporation of flexible single-stranded “gaps” in otherwise fully paired duplexes—producing clear evidence of an elementary lamellar (smectic-A) phase in DNA solutions—are two exciting developments that have opened avenues for discovery. Here, we report on a wider investigation of the nature and temperature dependence of smectic ordering in concentrated solutions of various “gapped” DNA (GDNA) constructs. We examine symmetric GDNA constructs consisting of two 48-base pair duplex segments bridged by a single-stranded sequence of 2 to 20 thymine bases. Two distinct smectic layer structures are observed for DNA concentration in the range [Formula: see text] mg/mL. One exhibits an interlayer periodicity comparable with two-duplex lengths (“bilayer” structure), and the other has a period similar to a single-duplex length (“monolayer” structure). The bilayer structure is observed for gap length [Formula: see text] 10 bases and melts into the cholesteric phase at a temperature between 30 °C and 35 °C. The monolayer structure predominates for gap length [Formula: see text] 10 bases and persists to [Formula: see text] C. We discuss models for the two layer structures and mechanisms for their stability. We also report results for asymmetric gapped constructs and for constructs with terminal overhangs, which further support the model layer structures.
- Published
- 2021
30. Enhanced piezoelectricity from highly polarizable oriented amorphous fractions in biaxially oriented poly(vinylidene fluoride) with pure β crystals
- Author
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Guanchun Rui, Elshad Allahyarov, Jia-Zhuang Xu, Yan-Fei Huang, Gan-Ji Zhong, Zhong-Ming Li, Philip L. Taylor, Ruipeng Li, Qiong Li, Lei Zhu, and Masafumi Fukuto
- Subjects
Materials science ,Polymers ,Science ,Chemie ,Analytical chemistry ,General Physics and Astronomy ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,Article ,General Biochemistry, Genetics and Molecular Biology ,Crystal ,Crystallinity ,Molecular dynamics ,chemistry.chemical_compound ,Polarizability ,Multidisciplinary ,Poling ,General Chemistry ,021001 nanoscience & nanotechnology ,Piezoelectricity ,0104 chemical sciences ,Amorphous solid ,chemistry ,0210 nano-technology ,Fluoride ,Actuators - Abstract
Piezoelectric polymers hold great potential for various electromechanical applications, but only show low performance, with |d33 | < 30 pC/N. We prepare a highly piezoelectric polymer (d33 = −62 pC/N) based on a biaxially oriented poly(vinylidene fluoride) (BOPVDF, crystallinity = 0.52). After unidirectional poling, macroscopically aligned samples with pure β crystals are achieved, which show a high spontaneous polarization (Ps) of 140 mC/m2. Given the theoretical limit of Ps,β = 188 mC/m2 for the neat β crystal, the high Ps cannot be explained by the crystalline-amorphous two-phase model (i.e., Ps,β = 270 mC/m2). Instead, we deduce that a significant amount (at least 0.25) of an oriented amorphous fraction (OAF) must be present between these two phases. Experimental data suggest that the mobile OAF resulted in the negative and high d33 for the poled BOPVDF. The plausibility of this conclusion is supported by molecular dynamics simulations., Piezoelectric polymers usually have rather low piezoelectric coefficients less than 30 pC/N. Here, the authors achieve a highly piezoelectric polymer (d33 = −62 pC/N) based on a poled biaxially oriented poly(vinylidene fluoride) with a pure β phase due to the mobile oriented amorphous fraction.
- Published
- 2021
31. Achieving Flat-on Primary Crystals by Nanoconfined Crystallization in High-Temperature Polycarbonate/Poly(vinylidene fluoride) Multilayer Films and Its Effect on Dielectric Insulation
- Author
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Eric Baer, Ruipeng Li, Masafumi Fukuto, Qiong Li, Lei Zhu, Xinyue Chen, Michael Ponting, and Deepak Langhe
- Subjects
Materials science ,02 engineering and technology ,Dielectric ,010402 general chemistry ,01 natural sciences ,GeneralLiterature_MISCELLANEOUS ,law.invention ,chemistry.chemical_compound ,law ,Power electronics ,Hardware_INTEGRATEDCIRCUITS ,General Materials Science ,Composite material ,Crystallization ,Polycarbonate ,ComputingMilieux_MISCELLANEOUS ,Ene reaction ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,Film capacitor ,chemistry ,ComputerSystemsOrganization_MISCELLANEOUS ,visual_art ,visual_art.visual_art_medium ,0210 nano-technology ,Fluoride - Abstract
To meet the stringent requirements of next-generation film capacitors for power electronics, multilayer films (MLFs) are fabricated with the advantage of achieving high temperature rating, high energy density, and reasonably low loss simultaneously. In this study, a high permittivity polar polymer, poly(vinylidene fluoride) (PVDF), is multilayered with a linear, low loss dielectric polymer such as high-temperature polycarbonate (HTPC). However, the dielectric loss of these MLFs was still high as compared with current state-of-the-art biaxially oriented polypropylene (BOPP) films. The goal of this work is to decrease the dielectric loss and enhance dielectric insulation by achieving flat-on primary PVDF crystals in MLFs via nanoconfined melt-recrystallization. Based on simultaneous small- and wide-angle X-ray scattering experiments, edge-on lamellar crystals were observed for all as-extruded MLFs, regardless of different PVDF layer thicknesses. However, after melting at 180 °C followed by recrystallization, flat-on primary crystals were successfully achieved when the PVDF layer thickness was below 39 nm. Above 78 nm for the PVDF layer, major edge-on primary crystals with minor flat-on secondary crystals were observed. From leakage current, breakdown, lifetime, and electric displacement-electric field loop studies, MLFs with the flat-on primary crystals exhibited reduced loss and enhanced dielectric insulation as compared to as-extruded MLFs and those with edge-on primary/flat-on secondary crystals. This was attributed to the effective blockage of charge carriers by the flat-on PVDF primary crystals and their reduced ferroelectric switching.
- Published
- 2020
32. Liquid crystal phases with unusual structures and physical properties formed by acute-angle bent core molecules
- Author
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Hao Wang, Min Gao, Oleg D. Lavrentovich, Yuriy A. Nastishin, Quan Li, Sergij V. Shiyanovskii, Bing-Xiang Li, Masafumi Fukuto, Ruipeng Li, and Sathyanarayana Paladugu
- Subjects
Condensed Matter::Soft Condensed Matter ,Core (optical fiber) ,Condensed Matter::Materials Science ,Crystallography ,Tetragonal crystal system ,Materials science ,Liquid crystal ,Phase (matter) ,Bent molecular geometry ,Polar ,Molecule ,Columnar phase - Abstract
The work explores liquid crystalline phases formed by acute-angle bent-core molecules. The material shows a very small splay modulus in the uniaxial nematic phase and a tetragonal positionally ordered columnar phase consisting of columns with alternating polar and non-polar packing of molecular pairs.
- Published
- 2020
33. Shear-induced polydomain structures of nematic lyotropic chromonic liquid crystal disodium cromoglycate
- Author
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Benjamin M. Yavitt, Hend Baza, Oleg D. Lavrentovich, Masafumi Fukuto, Taras Turiv, Bing-Xiang Li, and Ruipeng Li
- Subjects
Materials science ,Nucleation ,FOS: Physical sciences ,02 engineering and technology ,Condensed Matter - Soft Condensed Matter ,010402 general chemistry ,01 natural sciences ,law.invention ,Physics::Fluid Dynamics ,Optical microscope ,law ,Liquid crystal ,Lyotropic ,Condensed Matter - Materials Science ,Scattering ,Small-angle X-ray scattering ,Elastic energy ,Materials Science (cond-mat.mtrl-sci) ,General Chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,0104 chemical sciences ,Condensed Matter::Soft Condensed Matter ,Chemical physics ,Chromonic ,Soft Condensed Matter (cond-mat.soft) ,0210 nano-technology - Abstract
Lyotropic chromonic liquid crystals (LCLCs) represent aqueous dispersions of organic disk-like molecules that form cylindrical aggregates. Despite the growing interest in these materials, their flow behavior is poorly understood. Here, we explore the effect of shear on dynamic structures of the nematic LCLC, formed by 14 wt% water dispersion of disodium cromoglycate (DSCG). We employ in situ polarizing optical microscopy (POM) and small-angle and wide-angle X-ray scattering (SAXS/WAXS) to obtain independent and complementary information on the director structures over a wide range of shear rates. The DSCG nematic shows a shear-thinning behavior with two shear-thinning regions (Region I at [small gamma, Greek, dot above]1 s-1 and Region III at [small gamma, Greek, dot above]10 s-1) separated by a pseudo-Newtonian Region II (1 s-1[small gamma, Greek, dot above]10 s-1). The material is of a tumbling type. In Region I, [small gamma, Greek, dot above]1 s-1, the director realigns along the vorticity axis. An increase of [small gamma, Greek, dot above] above 1 s-1 triggers nucleation of disclination loops. The disclinations introduce patches of the director that deviates from the vorticity direction and form a polydomain texture. Extension of the domains along the flow and along the vorticity direction decreases with the increase of the shear rate to 10 s-1. Above 10 s-1, the domains begin to elongate along the flow. At [small gamma, Greek, dot above]100 s-1, the texture evolves into periodic stripes in which the director is predominantly along the flow with left and right tilts. The period of stripes decreases with an increase of [small gamma, Greek, dot above]. The shear-induced transformations are explained by the balance of the elastic and viscous energies. In particular, nucleation of disclinations is associated with an increase of the elastic energy at the walls separating nonsingular domains with different director tilts. The uncovered shear-induced structural effects would be of importance in the further development of LCLC applications.
- Published
- 2020
34. Enhanced Piezoelectricity from Highly Polarizable Oriented Amorphous Fractions in Biaxially Oriented Poly(vinylidene fluoride) with Pure β Crystals
- Author
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yanfei Huang, Guanchun Rui, Elshad Allahyarov, Ruipeng Li, Masafumi Fukuto, Gan-Ji Zhong, Jiazhuang Xu, Zhongming Li, Philip Taylor, and Lei Zhu
- Abstract
Piezoelectric polymers hold great potential for various electromechanical applications, but only show low performance, with |d33| < 30 pC/N. We prepared a highly piezoelectric polymer (d33 = -62 pC/N) based on a biaxially oriented poly(vinylidene fluoride) (BOPVDF, crystallinity = 0.52). After unidirectional poling, macroscopically aligned samples with pure β crystals were achieved, which showed an unprecedentedly high spontaneous polarization (Ps) of 140 mC/m2. Given the theoretical limit of Ps = 188 mC/m2 for the neat b crystal, the high Ps could not be explained by a simple two-phase model (i.e., the crystalline and the amorphous phases). Instead, we deduce that a significant amount (at least 0.25) of an oriented amorphous fraction (OAF) must be present between these two phases. Experimental data suggest that the mobile OAF resulted in the negative and high d33 for the poled BOPVDF. The plausibility of this conclusion was supported by molecular dynamics simulations.
- Published
- 2020
35. Future trends in synchrotron science at NSLS-II
- Author
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Yu-chen Karen Chen-Wiegart, Kevin G. Yager, John Hill, Gabriella Carini, Ignace Jarrige, Jean Jakoncic, Stuart I. Campbell, Masafumi Fukuto, Andrei Fluerasu, Peter Siddons, Mourad Idir, Yong S. Chu, and Toshi Tanabe
- Subjects
Engineering ,Low emittance ,business.industry ,02 engineering and technology ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,01 natural sciences ,Synchrotron ,law.invention ,law ,0103 physical sciences ,General Materials Science ,National Synchrotron Light Source II ,010306 general physics ,0210 nano-technology ,Telecommunications ,business ,National laboratory - Abstract
In this paper, we summarize briefly some of the future trends in synchrotron science as seen at the National Synchrotron Light Source II, a new, low emittance source recently commissioned at Brookhaven National Laboratory. We touch upon imaging techniques, the study of dynamics, the increasing use of multimodal approaches, the vital importance of data science, and other enabling technologies. Each are presently undergoing a time of rapid change, driving the field of synchrotron science forward at an ever increasing pace. It is truly an exciting time and one in which Roger Cowley, to whom this journal issue is dedicated, would surely be both invigorated by, and at the heart of.
- Published
- 2020
36. Can Relaxor Ferroelectric Behavior Be Realized for Poly(vinylidene fluoride-co-chlorotrifluoroethylene) [P(VDF–CTFE)] Random Copolymers by Inclusion of CTFE Units in PVDF Crystals?
- Author
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Thibaut Soulestin, Jun Lei, Fabrice Domingues Dos Santos, Ruipeng Li, Gan-Ji Zhong, Lei Zhu, Masafumi Fukuto, Yue Li, Jia-Zhuang Xu, Yan-Fei Huang, and Zhong-Ming Li
- Subjects
chemistry.chemical_classification ,Materials science ,Polymers and Plastics ,Electrostriction ,Organic Chemistry ,02 engineering and technology ,Polymer ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Inorganic Chemistry ,chemistry.chemical_compound ,chemistry ,Chemical engineering ,Materials Chemistry ,Copolymer ,Electric energy storage ,Inclusion (mineral) ,0210 nano-technology ,Chlorotrifluoroethylene ,Fluoride ,Relaxor ferroelectric - Abstract
Relaxor ferroelectric (RFE) polymers are attractive for various electrical applications such as electrostrictive actuation, electromechanical sensors, electric energy storage, and electrocaloric co...
- Published
- 2018
37. Sulfur Diffusion within Nitrogen-Doped Ordered Mesoporous Carbons Determined by in Situ X-ray Scattering
- Author
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Ruipeng Li, Masafumi Fukuto, Chao Wang, Yanfeng Xia, and Bryan D. Vogt
- Subjects
inorganic chemicals ,Materials science ,Chemical substance ,Diffusion ,chemistry.chemical_element ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,law.invention ,law ,Electrochemistry ,General Materials Science ,Spectroscopy ,Scattering ,X-ray ,Surfaces and Interfaces ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,Sulfur ,Cathode ,0104 chemical sciences ,Chemical engineering ,chemistry ,0210 nano-technology ,Science, technology and society ,Mesoporous material - Abstract
The low intrinsic conductivity of sulfur necessitates conductive additives, such as mesoporous carbons, to the cathode to enable high-performance metal-sulfur batteries. Simultaneous efforts to address polysulfide shuttling have introduced nitrogen-doped carbons to provide both conductivity and suppressed shuttling because of their strong interaction with sulfur. The strength of this interaction will impact the ability to fill the mesopores with sulfur via melt infusion. Here, we systematically investigate how nitrogen doping influences the rate that molten sulfur can infiltrate the mesopores and the overall extent of pore filling of highly ordered mesoporous doped carbons using in situ small angle X-ray scattering (SAXS). The similarity in electron density between molten sulfur and the soft carbon framework of the mesoporous material leads to a precipitous decrease in the scattered intensity associated with the ordered structure as voids are filled with sulfur. As the nitrogen doping increases from 1 to 20 at. %, the effective diffusivity of sulfur in the mesopores decreases by an order of magnitude (2.7 × 10
- Published
- 2018
38. Flat-On Secondary Crystals as Effective Blocks To Reduce Ionic Conduction Loss in Polysulfone/Poly(vinylidene fluoride) Multilayer Dielectric Films
- Author
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Donald E. Schuele, Michael Ponting, Xinyue Chen, Hua-Dong Huang, Deepak Langhe, Lei Zhu, Eric Baer, Ruipeng Li, and Masafumi Fukuto
- Subjects
Materials science ,Polymers and Plastics ,Organic Chemistry ,02 engineering and technology ,Dielectric ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Thermal conduction ,01 natural sciences ,0104 chemical sciences ,Ion ,Inorganic Chemistry ,chemistry.chemical_compound ,Differential scanning calorimetry ,chemistry ,Impurity ,Materials Chemistry ,Ionic conductivity ,Dielectric loss ,Polysulfone ,Composite material ,0210 nano-technology - Abstract
Recently, poly(vinylidene fluoride) (PVDF)-based multilayer films have demonstrated good potential as high energy density, high temperature, and low loss polymer dielectrics for advanced electrical and power applications. However, impurity ion conduction in the PVDF layers can cause significant dielectric loss at high temperatures. In this study, we discovered a facile melt-recrystallization method to suppress ionic conduction loss in polysulfone (PSF)/PVDF 50/50 (v/v) 33-layer films. By use of combined differential scanning calorimetry, broadband dielectric spectroscopy, and simultaneous small-angle X-ray scattering/wide-angle X-ray diffraction techniques, the underlying mechanism for the suppression of ionic conduction was unraveled. Basically, the growth and hierarchical organization of primary and secondary PVDF crystals confined in 400 nm layers played an important role. When the cooling rate during melt-recrystallization was high (e.g., ≥500 °C/min), small and poorly oriented secondary crystals betw...
- Published
- 2018
39. Thickness Limit for Alignment of Block Copolymer Films Using Solvent Vapor Annealing with Shear
- Author
-
Kevin G. Yager, Kevin A. Cavicchi, Bryan D. Vogt, Chao Zhang, Ruipeng Li, and Masafumi Fukuto
- Subjects
Materials science ,Polymers and Plastics ,Polydimethylsiloxane ,Scattering ,Small-angle X-ray scattering ,Annealing (metallurgy) ,Organic Chemistry ,Shear force ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Inorganic Chemistry ,chemistry.chemical_compound ,chemistry ,Materials Chemistry ,Copolymer ,Wafer ,Thin film ,Composite material ,0210 nano-technology - Abstract
The swelling and deswelling of a cross-linked polydimethylsiloxane (PDMS) pad adhered to a block copolymer (BCP) film during solvent vapor annealing (SVA) provides sufficient shear force to produce highly aligned domains over macroscopic dimensions in thin films. Here, we examine how far this alignment can propagate through the thickness of a BCP film to understand the limits for efficacy of the SVA-S (SVA with shear) process. Films of cylinder-forming polystyrene-block-polyisoprene-block-polystyrene (SIS) ranging from 100 nm to more than 100 μm are examined using the same processing conditions. The SIS surface in contact with the PDMS is always well-aligned, with Herman’s orientation parameter (S) exceeding 0.9 as determined from AFM micrographs, but the bottom surface in contact with the silicon wafer is not aligned for the thickest films. The average orientation through the film thickness was determined by transmission small-angle X-ray scattering (SAXS), with S decreasing gradually with increasing thi...
- Published
- 2018
40. Structure-induced switching of interpolymer adhesion at a solid–polymer melt interface
- Author
-
Mani Sen, Masafumi Fukuto, Justin Cheung, Naisheng Jiang, Sushil K. Satija, Wenduo Zeng, Maya K. Endoh, Guangcui Yuan, Yuma Morimitsu, Jan-Michael Y. Carrillo, Zhizhao Chen, Bobby G. Sumpter, and Tadanori Koga
- Subjects
chemistry.chemical_classification ,Materials science ,Nanostructure ,02 engineering and technology ,General Chemistry ,Polymer ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,01 natural sciences ,Paint adhesion testing ,0104 chemical sciences ,Overlayer ,Molecular dynamics ,Adsorption ,chemistry ,Physisorption ,Chemical engineering ,Adhesive ,0210 nano-technology - Abstract
Here we report a link between the interfacial structure and adhesive property of homopolymer chains physically adsorbed (i.e., via physisorption) onto solids. Polyethylene oxide (PEO) was used as a model and two different chain conformations of the adsorbed polymer were created on silicon substrates via the well-established Guiselin's approach: "flattened chains" which lie flat on the solid and are densely packed, and "loosely adsorbed polymer chains" which form bridges jointing up nearby empty sites on the solid surface and cover the flattened chains. We investigated the adhesion properties of the two different adsorbed chains using a custom-built adhesion testing device. Bilayers of a thick PEO overlayer on top of the flattened chains or loosely adsorbed chains were subjected to the adhesion test. The results revealed that the flattened chains do not show any adhesion even with the chemically identical free polymer on top, while the loosely adsorbed chains exhibit adhesion. Neutron reflectivity experiments corroborated that the difference in the interfacial adhesion is not attributed to the interfacial brodening at the free polymer-adsorbed polymer interface. Instead, coarse-grained molecular dynamics simulation results suggest that the tail parts of the loosely adsorbed chains act as "connector molecules", bridging the free chains and substrate surface and improving the interfacial adhesion. These findings not only shed light on the structure-property relationship at the interface, but also provide a novel approach for developing sticking/anti-sticking technologies through precise control of the interfacial polymer nanostructures.
- Published
- 2018
41. Pathway-engineering for highly-aligned block copolymer arrays
- Author
-
Masafumi Fukuto, Kevin G. Yager, Youngwoo Choo, Pawel W. Majewski, and Chinedum O. Osuji
- Subjects
Materials science ,Energy landscape ,02 engineering and technology ,Photothermal therapy ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Energy minimization ,Kinetic energy ,01 natural sciences ,0104 chemical sciences ,Cylinder (engine) ,law.invention ,Chemical physics ,law ,Metastability ,Copolymer ,General Materials Science ,Thin film ,0210 nano-technology - Abstract
While the ultimate driving force in self-assembly is energy minimization and the corresponding evolution towards equilibrium, kinetic effects can also play a very strong role. These kinetic effects, such as trapping in metastable states, slow coarsening kinetics, and pathway-dependent assembly, are often viewed as complications to be overcome. Here, we instead exploit these effects to engineer a desired final nano-structure in a block copolymer thin film, by selecting a particular ordering pathway through the self-assembly energy landscape. In particular, we combine photothermal shearing with high-temperature annealing to yield hexagonal arrays of block copolymer cylinders that are aligned in a single prescribed direction over macroscopic sample dimensions. Photothermal shearing is first used to generate a highly-aligned horizontal cylinder state, with subsequent thermal processing used to reorient the morphology to the vertical cylinder state in a templated manner. Finally, we demonstrate the successful transfer of engineered morphologies into inorganic replicas.
- Published
- 2018
42. Correction to 'Laponite-Incorporated UiO-66-NH2-Polyethylene Oxide Composite Membranes for Protection against Chemical Warfare Agent Simulants'
- Author
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Matthew A. Browe, John Landers, Masafumi Fukuto, Wesley O. Gordon, Trenton M. Tovar, Christopher J. Karwacki, Alex Balboa, and John J. Mahle
- Subjects
Inert ,chemistry.chemical_classification ,Materials science ,Diffuse reflectance infrared fourier transform ,Sulfide ,Composite number ,02 engineering and technology ,Permeation ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,chemistry.chemical_compound ,Membrane ,chemistry ,Chemical engineering ,Ultimate tensile strength ,General Materials Science ,0210 nano-technology ,Octane - Abstract
A strategy is developed to enhance the barrier protection of polyethylene oxide (PEO)-metal-organic framework (MOF) composite films against chemical warfare agent simulants. To achieve enhanced protection, an impermeable high-aspect-ratio filler in the form of Laponite RD (LRD) clay platelets was incorporated into a composite PEO film containing MOF UiO-66-NH2. The inclusion of the platelets aids in mitigating permeation of inert hydrocarbons (octane) and toxic chemicals (2-chloroethyl ethyl sulfide, 2-CEES) of dimensions/chemistry similar to prominent vesicant threats while still maintaining high water vapor transport rates (WVTR). By utilizing small-angle neutron scattering, small-angle X-ray scattering, and wide-angle X-ray scattering, the LRD platelet alignment of the films was determined, and the structure of the films was correlated with performance as a barrier material. Performance of the membranes against toxic chemical threats was assessed using permeation testing of octane and 2-CEES, a common simulant for the vesicant mustard gas, and breathability of the membranes was assessed using WVTR measurements. To assess their robustness, chemical exposure (in situ diffuse reflectance infrared Fourier transform spectroscopy) and mechanical (tensile strength) measurements were also performed. It was demonstrated that the barrier performance of the film upon inclusion of the LRD platelets exceeds that of other MOF-polymer composites found in the literature and that this approach establishes a new path for improving permselective materials for chemical protection applications.
- Published
- 2021
43. Rapid assessment of crystal orientation in semi-crystalline polymer films using rotational zone annealing and impact of orientation on mechanical properties
- Author
-
Jing Wang, Kevin G. Yager, Xuhui Xia, Stephen Z. D. Cheng, Bryan D. Vogt, Chao Wang, Ruipeng Li, Clinton G. Wiener, Masafumi Fukuto, and Changhuai Ye
- Subjects
Materials science ,Annealing (metallurgy) ,Modulus ,Crystal growth ,02 engineering and technology ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,01 natural sciences ,Grain size ,0104 chemical sciences ,Crystal ,Crystallinity ,Crystallography ,Spherulite ,Composite material ,0210 nano-technology ,Anisotropy - Abstract
Crystal orientation in semi-crystalline polymers tends to enhance their performance, such as increased yield strength and modulus, along the orientation direction. Zone annealing (ZA) orients the crystal lamellae through a sharp temperature gradient that effectively directs the crystal growth, but the sweep rate (VZA) of this gradient significantly impacts the extent of crystal orientation. Here, we demonstrate rotational zone annealing (RZA) as an efficient method to elucidate the influence of VZA on the crystal morphology of thin films in a single experiment using isotactic poly(1-butene), PB-1, as a model semi-crystalline polymer. These RZA results are confirmed using standard, serial linear ZA to tune the structure from an almost unidirectional oriented morphology to weakly oriented spherulites. The overall crystallinity is only modestly changed in comparison to isothermal crystallization (maximum of 55% from ZA vs. 48% for isothermal crystallization). However, the average grain size increases and the spherulites become anisotropic from ZA. Due to these structural changes, the Young's modulus of the oriented films, both parallel and perpendicular to the spherulite orientation direction, is significantly increased by ZA. The modulus does become anisotropic after ZA due to the directionality in the crystal structure, with more than a threefold increase in the modulus parallel to the orientation direction for the highest oriented film in comparison to the modulus from isothermal crystallization. RZA enables rapid identification of conditions to maximize orientation of crystals in thin polymer films, which could find utility in determining conditions to improve crystallinity and performance in organic electronics.
- Published
- 2017
44. Enhanced dielectric properties due to space charge-induced interfacial polarization in multilayer polymer films
- Author
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Xinyue Chen, Donald E. Schuele, Jung-Kai Tseng, Eric Baer, Matthew Mackey, Imre Treufeld, Ruipeng Li, Masafumi Fukuto, and Lei Zhu
- Subjects
chemistry.chemical_classification ,Polypropylene ,Work (thermodynamics) ,Materials science ,02 engineering and technology ,General Chemistry ,Polymer ,Dielectric ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Space charge ,0104 chemical sciences ,chemistry.chemical_compound ,Film capacitor ,chemistry ,visual_art ,Materials Chemistry ,visual_art.visual_art_medium ,Polycarbonate ,Composite material ,0210 nano-technology ,Spectroscopy - Abstract
With the recent advancement of power electronics, polymer film capacitors have become increasingly important. However, the low temperature rating (up to 85 °C) and low energy density (5 J cm−3 at breakdown) of state-of-the-art biaxially oriented polypropylene (BOPP) films have been limiting factors for advanced power electronics. Based on our recent work, multilayer films (MLFs), which consist of a high energy density polymer [e.g., poly(vinylidene fluoride) (PVDF)] and a high breakdown/low loss polymer [e.g., polycarbonate (PC)], have shown potential to achieve high energy density (13–17 J cm−3), enhanced breakdown strength, high temperature tolerance, and low loss simultaneously. In this study, the dielectric properties of PC/PVDF 50/50 32- and 256-layer (32L and 256L) films were investigated. The breakdown strength of the 32L film was as high as 800 MV m−1 at room temperature, as compared to 600 MV m−1 of PVDF and 750 MV m−1 of PC. The temperature rating of the 32L film reached 120 °C, higher than that of BOPP. In addition, it was observed that the 32L film with thicker PC layers exhibited a higher breakdown strength and a lower DC conductivity than the 256L film with thinner PC layers at elevated temperatures. These differences were attributed to the difference in the interfacial polarization of space charges, which was further verified by thermally stimulated depolarization current spectroscopy. From this study, we conclude that interfacial polarization endows MLFs with the desirable dielectric properties for next generation film capacitors.
- Published
- 2017
45. Novel Effects of Compressed CO2 Molecules on Structural Ordering and Charge Transport in Conjugated Poly(3-hexylthiophene) Thin Films
- Author
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Mani Sen, Levent Sendogdular, Bulent Akgun, Chang-Yong Nam, Naisheng Jiang, Tadanori Koga, Masafumi Fukuto, Maya K. Endoh, and Sushil K. Satija
- Subjects
Materials science ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,Isothermal process ,law.invention ,law ,Electrochemistry ,Side chain ,General Materials Science ,Lamellar structure ,Electrical measurements ,Crystallization ,Thin film ,Spectroscopy ,chemistry.chemical_classification ,Surfaces and Interfaces ,Polymer ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,0104 chemical sciences ,Crystallography ,chemistry ,Chemical engineering ,Melting point ,0210 nano-technology - Abstract
We report the effects of compressed CO, molecules as a novel plasticization agent for poly(3-hexylthiophene) (P3HT)-conjugated polymer thin films. In situ neutron reflectivity experiments demonstrated the excess sorption of CO, molecules in the P3HT thin films (about 40 nm in thickness) at low pressure (P = 8.2 MPa) under the isothermal condition of T = 36 degrees C, which is far below the polymer bulk melting point. The results proved that these CO2, molecules accelerated the crystallization process of the polymer on the basis of ex situ grazing incidence X-ray diffraction measurements after drying the films-via rapid depressurization to atmospheric pressure: both the out-of-plane lamellar ordering of the backbone chains and the intraplane pi-pi stacking of the side chains were significantly improved, when compared with those in the control P3HT films subjected to conventional thermal annealing (at T = 170 degrees C). Electrical measurements elucidated that the CO2-annealed P3HT thin films exhibited enhanced charge carrier mobility along with decreased background charge carrier concentration and trap density compared with those in the thermally annealed counterpart. This is attributed to the CO2-induced increase in polymer chain mobility that can drive the detrapping of molecular oxygen and healing of conformational defects in the polymer thin film. Given the universality of the excess sorption of CO2 regardless of the type of polymers, the present findings suggest that CO2 annealing near the critical point can be useful as a robust processing strategy for improving the structural and electrical characteristics of other semiconducting conjugated polymers and related systems such as polymer:fullerene bulk heterojunction films.
- Published
- 2016
46. A Kriging-Based Approach to Autonomous Experimentation with Applications to X-Ray Scattering
- Author
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Gregory S. Doerk, Marcus M. Noack, Ruipeng Li, James A. Sethian, Kevin G. Yager, and Masafumi Fukuto
- Subjects
0301 basic medicine ,Computer science ,lcsh:Medicine ,Context (language use) ,Bioengineering ,Parameter space ,Synthetic data ,Article ,03 medical and health sciences ,0302 clinical medicine ,Surrogate model ,Kriging ,lcsh:Science ,Multidisciplinary ,lcsh:R ,Computational science ,Experimental data ,Sampling (statistics) ,Scientific data ,Applied mathematics ,Other Physical Sciences ,Data set ,030104 developmental biology ,Design, synthesis and processing ,Data analysis ,Errors-in-variables models ,lcsh:Q ,Biochemistry and Cell Biology ,Generic health relevance ,Algorithm ,030217 neurology & neurosurgery ,Software - Abstract
Modern scientific instruments are acquiring data at ever-increasing rates, leading to an exponential increase in the size of data sets. Taking full advantage of these acquisition rates will require corresponding advancements in the speed and efficiency of data analytics and experimental control. A significant step forward would come from automatic decision-making methods that enable scientific instruments to autonomously explore scientific problems—that is, to intelligently explore parameter spaces without human intervention, selecting high-value measurements to perform based on the continually growing experimental data set. Here, we develop such an autonomous decision-making algorithm that is physics-agnostic, generalizable, and operates in an abstract multi-dimensional parameter space. Our approach relies on constructing a surrogate model that fits and interpolates the available experimental data, and is continuously refined as more data is gathered. The distribution and correlation of the data is used to generate a corresponding uncertainty across the surrogate model. By suggesting follow-up measurements in regions of greatest uncertainty, the algorithm maximally increases knowledge with each added measurement. This procedure is applied repeatedly, with the algorithm iteratively reducing model error and thus efficiently sampling the parameter space with each new measurement that it requests. We validate the method using synthetic data, demonstrating that it converges to faithful replica of test functions more rapidly than competing methods, and demonstrate the viability of the approach in an experimental context by using it to direct autonomous small-angle (SAXS) and grazing-incidence small-angle (GISAXS) x-ray scattering experiments.
- Published
- 2019
47. Instrumentation for In situ/Operando X-ray Scattering Studies of Polymer Additive Manufacturing Processes
- Author
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Marcus M. Noack, James A. Sethian, Kevin G. Yager, Gregory S. Doerk, Yuval Shmueli, Lutz Wiegart, M. Torres Arango, Masafumi Fukuto, Ruipeng Li, Gad Marom, Sang Soo Lee, Kristof Toth, Ron Pindak, Chinedum O. Osuji, and Miriam Rafailovich
- Subjects
In situ ,chemistry.chemical_classification ,Nuclear and High Energy Physics ,Materials science ,Scattering ,X-ray ,Material system ,Nanotechnology ,Optical Physics ,02 engineering and technology ,Polymer ,021001 nanoscience & nanotechnology ,01 natural sciences ,Atomic and Molecular Physics, and Optics ,Characterization (materials science) ,chemistry ,0103 physical sciences ,Instrumentation (computer programming) ,010306 general physics ,0210 nano-technology - Abstract
With new opportunities and challenges from additive manufacturing (AM), novel characterization approaches are needed to realize reliable and industry-transferrable material systems and processes. T...
- Published
- 2019
48. Strain rate dependent nanostructure of hydrogels with reversible hydrophobic associations during uniaxial extension
- Author
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Robert Weiss, Chao Wang, Kevin G. Yager, Clinton G. Wiener, Bryan D. Vogt, Ruipeng Li, and Masafumi Fukuto
- Subjects
Toughness ,Nanostructure ,Materials science ,Strain (chemistry) ,Small-angle X-ray scattering ,technology, industry, and agriculture ,macromolecular substances ,02 engineering and technology ,General Chemistry ,Strain rate ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,01 natural sciences ,0104 chemical sciences ,Chemical physics ,Self-healing hydrogels ,Deformation (engineering) ,0210 nano-technology ,Anisotropy - Abstract
An energy dissipation mechanism during deformation is required to impart toughness to hydrogels. Here we describe how in situ small angle X-ray scattering (SAXS) provides insight into possible energy dissipation mechanisms for a tough hydrogel based on an amphiphilic copolymer where nanoscale associations of the hydrophobic moieties act as effective crosslinks. The mechanical properties of the hydrogels are intimately coupled with the nanostructure that provides reversible crosslinks and evolves during deformation. As the extension rate increases, more mechanical energy is dissipated from rearrangements of the crosslinks. The scattering is consistent with hopping of hydrophobes between the nanoscale aggregates as the primary rearrangement mechanism. This rearrangement changes the network conformation that leads to non-affine deformation, where the change in the nanostructure dimension from SAXS is less than 15% of the total macroscopic strain. These nanostructure changes are rate dependent and correlated with the relaxation time of the hydrogel. At low strain rate (0.15% s-1), no significant change of the nanostructure was observed, whereas at higher strain rates (1.5% s-1 and 8.4% s-1) significant nanostructure anisotropy occurred during extension. These differences are attributed to the ability for the network chains to rearrange on the time scale of the deformation; when the characteristic time for extension is longer than the average segmental relaxation time, no significant change in nanostructure occurs on uniaxial extension. These results illustrate the importance of strain rate in the mechanical characterization and consideration of relaxation time in the design of tough hydrogels with reversible crosslinks.
- Published
- 2018
49. Correction: Shear-induced polydomain structures of nematic lyotropic chromonic liquid crystal disodium cromoglycate
- Author
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Hend Baza, Taras Turiv, Bing-Xiang Li, Ruipeng Li, Benjamin M. Yavitt, Oleg D. Lavrentovich, and Masafumi Fukuto
- Subjects
Shear (sheet metal) ,Materials science ,Liquid crystal ,Disodium cromoglycate ,Lyotropic ,Chromonic ,Thermodynamics ,General Chemistry ,Soft matter ,Condensed Matter Physics - Abstract
Correction for ‘Shear-induced polydomain structures of nematic lyotropic chromonic liquid crystal disodium cromoglycate’ by Hend Baza et al., Soft Matter, 2020, 16, 8565–8576.
- Published
- 2021
50. Transmission X-ray scattering as a probe for complex liquid-surface structures
- Author
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Dmytro Nykypanchuk, Masafumi Fukuto, Ivan Kuzmenko, and Lin Yang
- Subjects
Diffraction ,Nuclear and High Energy Physics ,Radiation ,Materials science ,business.industry ,Small-angle X-ray scattering ,Scattering ,02 engineering and technology ,Substrate (electronics) ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Synchrotron ,0104 chemical sciences ,law.invention ,Optics ,Chemical physics ,law ,Monolayer ,Meniscus ,Specular reflection ,0210 nano-technology ,business ,Instrumentation - Abstract
The need for functional materials calls for increasing complexity in self-assembly systems. As a result, the ability to probe both local structure and heterogeneities, such as phase-coexistence and domain morphologies, has become increasingly important to controlling self-assembly processes, including those at liquid surfaces. The traditional X-ray scattering methods for liquid surfaces, such as specular reflectivity and grazing-incidence diffraction, are not well suited to spatially resolving lateral heterogeneities due to large illuminated footprint. A possible alternative approach is to use scanning transmission X-ray scattering to simultaneously probe local intermolecular structures and heterogeneous domain morphologies on liquid surfaces. To test the feasibility of this approach, transmission small- and wide-angle X-ray scattering (TSAXS/TWAXS) studies of Langmuir films formed on water meniscus against a vertically immersed hydrophilic Si substrate were recently carried out. First-order diffraction rings were observed in TSAXS patterns from a monolayer of hexagonally packed gold nanoparticles and in TWAXS patterns from a monolayer of fluorinated fatty acids, both as a Langmuir monolayer on water meniscus and as a Langmuir–Blodgett monolayer on the substrate. The patterns taken at multiple spots have been analyzed to extract the shape of the meniscus surface and the ordered-monolayer coverage as a function of spot position. These results, together with continual improvement in the brightness and spot size of X-ray beams available at synchrotron facilities, support the possibility of using scanning-probe TSAXS/TWAXS to characterize heterogeneous structures at liquid surfaces.
- Published
- 2016
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