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Successful practical implementation of bioelectrochemical systems (BES) requires developing affordable electrode structures that promote efficient electrical communication with microbes. Recent efforts have centered on immobilizing bacteria with organic semiconducting polymers on electrodes via electrochemical methods. This approach creates a fixed biocomposite that takes advantage of the increased electrode's electroactive surface area (EASA). Here, it is demonstrated that a biocomposite comprising the water‐soluble conjugated polyelectrolyte CPE‐K and electrogenic Shewanella oneidensis MR‐1 can self‐assemble with carbon paper electrodes, thereby increasing its biocurrent extraction by ≈6‐fold over control biofilms. A ≈1.5‐fold increment in biocurrent extraction is obtained for the biocomposite on carbon paper relative to the biocurrent extracted from gold‐coated counterparts. Electrochemical characterization revealed that the biocomposite stabilized with the carbon paper more quickly than atop flat gold electrodes. Cross‐sectional images show that the biocomposite infiltrates inhomogeneously into the porous carbon structure. Despite an incomplete penetration, the biocomposite can take advantage of the large EASA of the electrode via long‐range electron transport. These results show that previous success on gold electrode platforms can be improved when using more commercially viable and easily manipulated electrode materials. [ABSTRACT FROM AUTHOR]

Herein, a novel, facile, and versatile approach to fabricate highly flexible and conductive paper is proposed by electroless deposition (ELD) with the assistance of aminocellulose as the interface layer. The obtained Cu nanoparticles (NPs)‐coated cellulose paper is highly conductive with a significant low resistance of 0.38 Ω sq−1 after only 10 min of ELD treatment. This conductive cellulose paper shows excellent stability when it suffers from bending, folding, and tape adhesion cycles. With the same method, the Cu NPs can also be successfully deposited on the polypropylene (PP)‐filled hybrid paper. The conductive paper exhibits very smooth and hydrophobic surface with high reflection, which can be used for special electronic devices. In a word, the fabrication of aminocellulose interface permits a controlled ELD of metal nanoparticles on paper substrate, and this mild and low‐cost method opens up new opportunities for large‐scale production of flexible and wearable electronics. [ABSTRACT FROM AUTHOR]

A photo-responsive multi-bilayered film consisting of azobenzene polymer liquid crystals (PA6Az1) and poly(vinyl alcohol) (PVA) has been prepared on a glass substrate by alternate spin coating of the polymer solutions. The reflectivity of the multi-bilayered film disappears by annealing at 80 °C. The disappearance of the reflection by the annealing is related to the thermal out-of-plane molecular orientation of PA6Az1 even in the multi-bilayered film, which leads to a very small difference in refractive indices between PA6Az1 and PVA. The reflectance of the multi-bilayered film is increased again by UV irradiation because of the transformation from the out-of-plane orientation to an in-plane random orientation. In this way, on-off switching of the reflection is achieved by combination of the thermally spontaneous out-of-plane molecular orientation and following photoisomerization of PA6Az1 comprising the multi-bilayered film., (Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Inkjet-printed paper-based volatile organic compound (VOC) sensor strips imaged with polydiacetylenes (PDAs) are developed. A microemulsion ink containing bisurethane-substituted diacetylene (DA) monomers, 4BCMU, was inkjet printed onto paper using a conventional inkjet office printer. UV irradiation of the printed image allowed fabrication of blue-colored poly-4BCMU on the paper and the polymer was found to display colorimetric responses to VOCs. Interestingly, a blue-to-yellow color change was observed when the strip was exposed to chloroform vapor, which was accompanied by the generation of green fluorescence. The principal component analysis plot of the color and fluorescence images of the VOC-exposed polymers allowed a more precise discrimination of VOC vapors. [ABSTRACT FROM AUTHOR]

Multiwalled carbon nanotubes in the form of bucky papers were modified using Ar/O(2) plasma and thereafter melt-mixed into polycarbonate. The effect of plasma modification on the nanotubes was followed by XPS, indicating the formation of carboxylic or ester groups at the nanotube surfaces. In the melt-mixed nanocomposites, the modified nanotubes exhibited a better macrodispersion and better phase adhesion to the matrix as evidenced by morphological investigations. The electrical percolation threshold was not altered and occurred below 0.5 wt.-% nanotubes. The mechanical properties were improved by having higher values of stress at yield, stress beyond the yield point, and strain at break illustrating the effect of both better dispersion and enhanced phase adhesion., (Copyright © 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

This work has prepared polymeric self‐assembled monolayer (SAM) sensors for the detection of trace volatile nitroaromatic compound (NAC) explosives by fluorescence quenching. A typical aggregation‐induced emission (AIE) luminogen 1,1,2,2‐tetraphenylethene (TPE) polymerizes into PTPE to increase the fluorescence intensity in the SAMs, and the phosphoric acid acts as the anchor group to form stable covalent bonds with the Al2O3 substrate. This design takes advantage of the high sensitivity and good stability of SAMs, and high fluorescence intensity, and "wire effect" of the conjugated polymers. The polymeric SAM sensors are prepared on the Al2O3 silicon wafer and testing paper. Both of them show good response speed, reversibility, selectivity, and sensitivity. The detection limits down to 0.07, 0.35, and 4.11 ppm for TNT, DNB, and NB, respectively, are achieved on the inorganic testing paper. Furthermore, due to the higher fluorescence intensity by interlacing and overlapping of fibers, the detection of the paper can be distinguished by naked eyes even with a low‐power handheld UV lamp, which provides an experimental basis for the development of cheap and easy trace NAC explosive sensors. [ABSTRACT FROM AUTHOR]

A preview of the articles "Bacterial Cellulose Nanopaper as Reinforcement for Polylactide Composites: Renewable Thermoplastic NanoPaPreg" by M. Tang, C. K. Williams , A. Bismarck, "Supramolecular Adhesives to Hard Surfaces: Adhesion Between Host Hydrogels and Guest Glass Substrates Through Molecular Recognition" by Y. Takashima , T. Sahara , T. Sekine , and "Shape Memory Particles Capable of Controlled Geometric and Chemical Asymmetry made from Aliphatic Polyesters" by S. M. Brosnan, A.M. S. Jackson, Y. Wang, which appeared in the periodical "Macromolecular Rapid Communications" in issue 35, 2014, is presented.

Bacterial cellulose (BC) is often regarded as a prime candidate nano-reinforcement for the production of renewable nanocomposites. However, the mechanical performance of most BC nanocomposites is often inferior compared with commercially available polylactide (PLLA). Here, the manufacturing concept of paper-based laminates is used, i.e., 'PaPreg,' to produce BC nanopaper reinforced PLLA, which has been called 'nanoPaPreg' by the authors. It is demon­strated that high-performance nanoPaPreg ( vf = 65 vol%) with a tensile modulus and strength of 6.9 ± 0.5 GPa and 125 ± 10 MPa, respectively, can be fabricated. It is also shown that the tensile properties of nanoPaPreg are predominantly governed by the mechanical performance of BC nanopaper instead of the individual BC nanofibers, due to difficulties impregnating the dense nanofibrous BC network. [ABSTRACT FROM AUTHOR]

The development of bio‐based polymer materials, such as polylactic acid (PLA) ‐based polymers, is an effective strategy to reduce dependence on petrochemical‐based polymers. However, the preparation of bio‐based polymers with high barrier properties is a major challenge. To overcome this challenge, a nacreous layer structure with a ' brick and mud ' pattern is mimicked to improve the overall performance of the material. In this paper, Poly (L‐lactic acid) (PLLA) and Polypropylene Glycol (PPG) was combined to prepare bio‐based polyurethane (PU‐PLLA), which is used as the slurry structure of nacreous layer. The bio‐based biomimetic composite membrane (PU‐PLLA/BN) is then obtained by adding boron nitride (BN, brick structure of pearl layer) to it. The water vapor permeability test results show that the permeability of PU‐PLLA material can be reduced by more than 50% by 5 wt.% BN, which is because the addition of BN can increase the length and tortuosity of the gas molecular diffusion path in the composite. Therefore, this pearl‐inspired PU‐PLLA/BN film has excellent moisture resistance, which opens up a broad road for the practical application of PLLA in flexible laminated packaging. [ABSTRACT FROM AUTHOR]

Benzaldehyde-functional cellulose paper sheets have been synthesized via tosylation of cellulose (Whatman No 5) followed by addition of p-hydroxy benzaldehyde. Via UV-induced Paterno-Büchi [2+2] cycloaddition reactions, these aldehyde functional surfaces are grafted with triallylcyanurate, trimethylolpropane allyl ether, and vinyl chloroacetate. In the following, allyl-functional polymers (poly(butyl acrylate), pBA, Mn = 6990 g mol(-1) , Đ = 1.12 and poly(N-isopropyl acrylamide), pNIPAAm, Mn = 9500 g mol(-1) , Đ = 1.16) synthesized via reversible addition fragmentation chain transfer polymerization are conjugated to the celloluse surface in a UV-induced grafting-to approach. With pBA, hydrophobic cellulose sheets are obtained (water contact angle 116°), while grafting of pNIPAAm allows for generation of "smart" surfaces, which are hydrophilic at room temperature, but that become hydrophobic when heated above the characteristic lower critical solution temperature (93° contact angle). The Paterno-Büchi reaction has been shown to be a versatile synthetic tool that also performs well in grafting-to approaches whereby its overall performance seems to be close to that of radical thiol-ene reactions., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Immobilizing cellulase for improving its hydrolysis activity and recyclability is critical for a cost‐effective and environment‐friendly conversion of cellulosic biomass. However, developing a strategy for achieving a high mass‐transfer rate and good separation efficiency between an insoluble cellulose substrate and cellulase remains difficult. Instead of the traditional method, a single‐enzyme molecular modification method is used in this study. To modify cellulase and provide it with a temperature–pH dual responsive property, systemized poly(acrylic‐acrylonitrile) (PAA–PAN) molecular arms are used. The modified cellulase can reversibly transform between liquid and solid phases. In the liquid phase, the modified cellulase can adjust its active center, increasing its hydrolysis efficiency and separation efficiency. Cellulase and glucose products can be easily separated in the solid phase, allowing the reuse of cellulase. The results show that the modified cellulase's hydrolysis efficiency is comparable to that of free cellulase and that the modified enzyme preserves more than 60% of its initial activity after 15 batches of efficient hydrolysis. Thus, the proposed modification route considerably lowers the cost of cellulose enzymatic hydrolysis. [ABSTRACT FROM AUTHOR]

Exploring the ring‐opening polymerization (ROP) mechanism of benzoxazines is a fundamental issue in benzoxazine chemistry. Though some research papers on the topic have been reported, the ROP mechanism of mono‐benzoxazines is still elusive. The key point for mechanistic studies is to determine and characterize the structure and formation pathways of the products generated in ROP. In this paper, the ROP of a vanillin‐furfurylamine‐based benzoxazine and a mono‐azomethine derivative is studied with differential scanning calorimetry, fourier transform infrared spectroscopy, nuclear magnetic resonance, and electrospray ionization mass spectrometry, respectively. The results show that the products consist of a range of cationic species, zwitterions, fragments, and series of cyclic and linear oligomers of varying molecular sizes. It is proposed that both mono‐benzoxazines undergo thermally activated cationic ring‐opening oligomerization via zwitterion intermediates. Upon thermal induction, multi‐bond‐cleavage takes place to form various zwitterionic intermediates, which react with a monomer, a fragment, or a second zwitterion by several pathways to generate cyclic and linear oligomers. [ABSTRACT FROM AUTHOR]

High‐performance, versatile epoxy resins (EPs) are used in a variety of fields, but the manufacture of transparent, fireproof, and strong EPs remains a major challenge. The hyperbranched, multifunctional flame retardant (DSi) is prepared by using diethanolamine, polyformaldehyde, diphenylphosphine oxide, and phenyltrimethoxysilane as raw materials in this work. When the additional amount of DSi is only 2 wt.%, the EP‐DSi2 sample reaches a vertical burning (UL‐94) V‐0, and its limiting oxygen index (LOI) is 32.8%. When the content of DSi is 3 wt.%, the peak heat release rate (PHRR) and total smoke production (TSP) of EP‐DSi samples are 43.8% and 21.4% lower than those of EP. The good compatibility of DSi and EP endows EP‐DSi with high transparency, and the hyperbranched structure of DSi makes EP‐DSi have obviously enhanced mechanical strength and toughness. The enhanced fire safety of EP‐DSi is mainly due to the promoting carbonization and radical quenching effects of DSi. This paper offers a comprehensive design concept aimed at creating high‐performance epoxy resins with good optical, mechanical, and flame‐retardant properties, which have broad application prospects. [ABSTRACT FROM AUTHOR]

Controlled branched structures remain a key synthetic limitation for monomeric tissue adhesives because their on‐site polymerization that enables adhesion formation requires rapid kinetics, high conversion, and straightforward setup. In this context, site‐specific branching initiation by using evolmers is potentially effective for structural control; however, the efficiency and kinetics in current reaction setups persists to be a major challenge. In this paper, an evolmer induces a controlled branching polymerization of cyanoacrylate amid the high monomer reactivity useful in rapid adhesion. The contrasting reactivities between the vinyl and the initiating groups in the evolmer molecule generate a kinetic pathway that favors a control‐enabling branching mechanism. Through density functional theory calculations, the reaction pathway toward branching is shown to kinetically favor site‐specific initiation by six orders of magnitude than the route toward non‐specificity. Reaction monitoring confirms the branching polymerization after the polymerization with the evolmer forms a more compact structure than the linear counterpart. Control of branching density is demonstrated in rapid polymerizations within minutes and in polymerizations completed in an instant. These results provide a template for achieving site‐specific branching initiation during adhesion formation and, broadly, where conditions for kinetic control are necessary. [ABSTRACT FROM AUTHOR]

The need for eco‐friendly cooling materials and material recycling are two urgent challenges to address. In this paper, the role of the ground tyre rubber treatment (cryo‐grinding and devulcanization) is investigated on the tensile and elastocaloric properties of Natural rubber (NR)/ ground tyre rubber (GTR). The GTR particles that are sieved (<63µm) and devulcanized by microwave irradiation (1 min at 800Watts) exhibit a low network chain density (0.53 × 10−4 mol.cm−3) resulting from crosslinks breakage and rubber chains scission, as supported by FTIR showing a decrease of S─S, C─S, and C─C bonds. The NR/GTR blends show a high elastocaloric effect as compared to the pristine NR, which can be ascribed to the high content of carbon black in the GTR (52 wt.%) and also the high level of devulcanization of the GTR. NR/GTR blends reach a heating of +8 °C and a cooling of >−6 °C, resulting in a material's coefficient of performance COPmat = 2.8–3 compared to 2.6 for the pristine NR. The concomitant effect of cryogrinding and microwave devulcanization is proposed as a way to improve the tensile and elastocaloric properties of natural rubber/waste rubber blends for their possible integration into elastocaloric devices for heating/cooling applications. [ABSTRACT FROM AUTHOR]

In recent years, the automotive industry has made significant progress in integrating multifunctional sensors to improve vehicle performance, safety, and efficiency. As the number of integrated sensors keeps increasing, there is a growing interest in alternative energy sources. Specifically, self‐powered sensor systems based on energy harvesting are drawing much attention, with a main focus on sustainability and reducing reliance on typical batteries. This paper demonstrates the use of triboelectric nanogenerators (TENGs) in a computer mouse for efficient energy harvesting and in automobile braking systems for safety applications using SrBi2Ta2O9 (SBTO) perovskite, blended PDMS composite operating in free‐standing mode with an interdigitated patterned aluminum electrode. This self‐powered sensor is capable of distinguishing between normal and abnormal braking patterns using digital signal processing techniques. It is noteworthy that the addition of 15% wt. of the SBTO in PDMS composite‐based TENG delivered 13.5 V, 45 nA, and an output power of 0.98 µW. This new combination of energy harvesting and safety applications enables real‐time monitoring and predictive maintenance in the automotive industry. [ABSTRACT FROM AUTHOR]

The pursuit of innovative organic materials and the examination of the “structure‐function” correlation in lithium‐ion batteries (LIBs) are crucial and highly desirable. Current research focuses on the creation of novel conjugated organic polymers with polycarbonyl groups and examining the impact of electrode structure on the function of lithium‐ion batteries. In this paper, two novel cyanovinylene‐based conjugated organic polymers, NBA‐TFB and NBA‐TFPB, are synthesized using a Knoevenagel condensation reaction with naphthalene diimide as the integral unit. The performance of NBA‐TFB and NBA‐TFPB as cathodes in lithium‐ion batteries is investigated. Improved conductivity and increased active site density in NBA‐TFPB resulted in superior electrochemistry compared to NBA‐TFB. Specifically, NBA‐TFPB exhibited a larger reversible capacity (87.58 mAh g−1 at 0.2C and 88.34% retention after 100 cycles), exceptional rate capability (66.13 mAh g−1 at 5C), and robust cycling stability (99.58% coulombic efficiency at 1C and 60.71% retention after 2000 cycles). This study expands the family of diimide‐based naphthalene polymers and provides a strategy for enhancing the performance of organic electrode materials containing polycarbonyl structure. [ABSTRACT FROM AUTHOR]

Antibacterial materials with high hydrophobicity have drawbacks such as protein adsorption, bacterial contamination, and biofilm formation, which are responsible for some serious adverse health events. Therefore, antibacterial materials with high hydrophilicity are highly desired. In this paper, UV‐curable antibacterial materials are prepared from silicone−containing Choline chloride (ChCl) functionalized hyperbranched quaternary ammonium salts (QAS) and tri−hydroxylethyl acrylate phosphate (TAEP). The materials show high hydrophilic performance because their water contact angle is as low as 19.3°. The materials also exhibit quite high antibacterial efficiency against S. aureus over 95.6%, fairly high transmittance over 90%, and good mechanical performance with tensile strength as high as 6.5 MPa. It reveals that it is a feasible strategy to develop antibacterial materials with low hydrophobicity from silicone‐modified ChCl‐functionalized hyperbranched QAS. [ABSTRACT FROM AUTHOR]

Durable functionalization on polypropylene (PP) surfaces is always a key problem to besolved. Coatings with low surface energy peel off easily especially under extreme conditions, owing to their weak adhesion. In this paper, side groups of both polyhedral oligomeric silsesquioxane (POSS) and alkane are grafted to polypentafluorophenyl methacrylate (PFP), and then PP blends with these side‐group modified PFP are obtained through a melt‐blending process. It is found that POSS can result in surface segregation and provide hydrophobicity in blends. Microfibers are formed because of the orientation effect during the tensile testing, which furtherly promotes mechanical strength. Significantly, alkaneside‐groups can be entangled with PP segments, which brings about cross linking. Therefore, with crosslinking and synchronous orientation of POSS, the elongation at the break of blends is greatly increased up to 974%. The final blend demonstrates quite durable hydrophobicity under many extreme conditions, such as repeated tape peeling, ultrasonic washing, strong friction, and soaking in strong acid (pH = 1), strong alkali (pH = 14) and alcohol. The heat and UV resistance of the blend are also obviously improved. This study will develop anovel and facile strategy to endow PP with durable hydrophobicity as well as greatly enhanced mechanical properties. [ABSTRACT FROM AUTHOR]

The development of peptidomimetics to modulate the conformational profile of peptides has been extensively studied in the fields of biological and medicinal chemistry. However, large‐scale synthesis of peptidomimetics with both an ordered sequence and a controlled secondary structure is highly challenging. In this paper, the framework of peptidomimetics has been designed to be alternating an achiral α,α‐disubstituted α‐amino acid unit and a chiral α‐methylphenylalanine unit. The polymers are synthesized via invented Ugi reaction‐based polycondensation technique. The chiral higher‐order structures of the alternating peptides are evaluated mainly through circular dichroism (CD) spectroscopy. The UV–Vis and CD spectra of the polymers in three solvents are systematically measured at various temperatures. The anisotropic factors of CD (gCD) values are calculated to know the chiroptical response. The results indicate the characteristic conformational behaviors. In a polar solvent, the hydrogen bonds between the N‐H group of MePhe unit and the C=O of α,α‐diphenylglycine unit outweigh the intraresidue hydrogen bonds in α,α‐diphenylglycine unit, leading to the formation of a prevailing preferred‐handed 310‐helical conformation. On the other hand, in a less polar solvent, the intrachain hydrogen bonds switch to intraresidue hydrogen bonds in α,α‐diphenylglycine unit, which make the polymer adopting a prevailing extended planar C5‐conformation. [ABSTRACT FROM AUTHOR]

Abstract: Liquid crystal elastomers are among the best candidates for artificial muscles, and the materials of choice when constructing microscale robotic systems. Recently, significant efforts are dedicated to designing stimuli‐responsive actuators that can reproduce the shape‐change of soft bodies of animals by means of proper external energy source. However, transferring material deformation efficiently into autonomous robotic locomotion remains a challenge. This paper reports on a miniature inching robot fabricated from a monolithic liquid crystal elastomer film, which upon visible‐light excitation is capable of mimicking caterpillar locomotion on different substrates like a blazed grating and a paper surface. The motion is driven by spatially uniform visible light with relatively low intensity, rendering the robot “human‐friendly,” i.e., operational also on human skin. The design paves the way toward light‐driven, soft, mobile microdevices capable of operating in various environments, including the close proximity of humans. [ABSTRACT FROM AUTHOR]

Two key challenges in the multidisciplinary field of sequence‐controlled polymers are their efficient synthesis and the establishment of correlation with polymer properties. In this context, in this paper, gradient architecture in the hydrophobic tail of an amphiphile is implemented and synthesized for a fixed hydrophilic unit (polyethylene glycol, PEG), by means of two monomers (2‐hydroxypropyl methacrylate, HPMA, and diacetone acrylamide, DAAM) of contrasting reactivities. The resulting non‐biochemical gradient sequence‐controlled polymers are generated from a one‐pot, homogeneous mixture through a PET‐RAFT‐PISA (photoinduced electron/energy transfer‐reversible addition‐fragmentation chain transfer‐polymerization‐induced self‐assembly) method. In addition, the initial concentration ratio of the monomers in the gradient is varied as an input for a set of fixed experimental parameters and conditions, and its correlation with kinetics, gradient and self‐assembled morphologies is established, as the output of the process. These results are extensively corroborated via nuclear magnetic resonance (NMR) spectroscopy analysis, together with transmission electron microscopy (TEM) images, dynamic light scattering (DLS), and gel permeation chromatography (GPC) experiments. These results have implications for chemical computation carried out by PISA, programmable self‐assembly, information storage, biomimetics, origins of life and synthetic protocell studies. [ABSTRACT FROM AUTHOR]

Polyethylene (PE), a highly prevalent non‐biodegradable polymer in the field of plastics, presents a waste management issue. To alleviate this issue, bio‐based PE (bio‐PE), derived from renewable resources like corn and sugarcane, offers an environmentally friendly alternative. This review discusses various production methods of bio‐PE, including fermentation, gasification, and catalytic conversion of biomass. Interestingly, the bio‐PE production volumes and market are expanding due to the growing environmental concerns and regulatory pressures. Additionally, the production of PE and bio‐PE biocomposites using agricultural waste as filler materials, highlights the growing demand for sustainable alternatives to conventional plastics. According to previous studies, addition of ≈50% defibrillated corn and abaca fibers into bio‐PE matrix and a compatibilizer, results in the highest Young's modulus of 4.61 and 5.81 GPa, respectively. These biocomposites have potential applications in automotive, building construction, and furniture industries. Moreover, the advancement made in abiotic and biotic degradation of PE and PE biocomposites is elucidated to address their environmental impacts. Finally, the paper concludes with insights into the opportunities, challenges, and future perspectives in the sustainable production and utilization of PE and bio‐PE biocomposites. In summary, production of PE and bio‐PE biocomposites can contribute to a cleaner and sustainable future. [ABSTRACT FROM AUTHOR]

The raw materials of Poly(ethylene terephthalate) (PET) are derived from petroleum‐based resources, which are no sustainable. Therefore, previous researchers introduced biomass‐derived 2,5‐tetrahydrofurfuryl dimethanol (THFDM) into PET. However, its heat resistance has decreased compared to PET. In this paper, a novel bio‐based copolyester, poly(ethylene glycol‐co‐2,5‐tetrahydrofuran dimethanol‐co‐isosorbide terephthalate) (PEIFT), is prepared by introducing biomass‐derived isosorbide (ISB) and THFDM into the PET chains through melting copolymerization process. With the introduction of ISB content, copolyesters' hydrophilicity and rigidity improve. Compared to PET, glass transition temperature (Tg) increases by over 5 °C. In addition, the toughness and spinning performance of PEIFT have also been improved as a result of the addition of THFDM components. The hydrophobicity of PEIFTs electrospinning is greatly improved, with a contact angle exceeding 135°. Finally, due to the good hydrophobicity of PEIFTs nanofibers, they have potential application value in the manufacture of hydrophobic nanofiber and filter films. Given its biomass source and excellent performance, they make it easier to replace materials derived from petroleum. [ABSTRACT FROM AUTHOR]

In 2007, polydopamine (PDA) films were shown to be formed spontaneously on the surface of all known classes of materials by simply dipping those substrates in an aerated dopamine solution at pH = 8.5 in the presence of Tris(hydroxymethyl) amino methane buffer. This universal deposition method has raised a burst of interest in surface science, owing not only to the universality of this water based one pot deposition method but also to the ease of secondary modifications. Since then, PDA films and particles are shown to have applications in energy conversion, water remediation systems, and last but not least in bioscience. The deposition of PDA films from aerated dopamine solutions is however a slow and inefficient process at ambient temperature with most of the formed material being lost as a precipitate. This incited to explore the possibility to get PDA and related films based on other catecholamines, using other oxidants than dissolved oxygen and other deposition methods. Those alternatives to get PDA and related films are reviewed and compared in this paper. It will appear that many more investigations are required to get better insights in the relationships between the preparation method of PDA and the properties of the obtained coatings. [ABSTRACT FROM AUTHOR]

Currently, heat accumulation has seriously affected the stabilities and life of electronic devices. Polyimide (PI) film with high thermal conductivity coefficient (λ) has long been held up as an ideal solution for heat dissipation. Based on the thermal conduction mechanisms and classical thermal conduction models, this review presents design ideas of PI films with microscopically ordered liquid crystalline structures which are of great significance for breaking the limit of λ enhancement and describes the construction principles of thermal conduction network in high‐λ filler strengthened PI films. Furthermore, the effects of filler type, thermal conduction paths, and interfacial thermal resistances on thermally conductive behavior of PI film are systematically reviewed. Meanwhile, this paper summarizes the reported research and provides an outlook on the future development of thermally conductive PI films. Finally, it is expected that this review will give some guidance to future studies in thermally conductive PI film. [ABSTRACT FROM AUTHOR]

Biomimetic actuators are critical components of bionics research and have found applications in the fields of biomedical devices, soft robotics, and smart biosensors. This paper reports the first study of nanoassembly topology‐dependent actuation and shape memory programming in biomimetic 4D printing. Multi‐responsive flower‐like block copolymer nanoassemblies (vesicles) are utilized as photocurable printing materials for digital light processing (DLP) 4D printing. The flower‐like nanoassemblies enhance thermal stability, attributed to their surface loop structures on the shell surfaces. Actuators prepared from these nanoassemblies display topology‐dependent bending in response to pH and temperature‐programmable shape memory properties. Biomimetic octopus‐like soft actuators are programmed with multiple actuation patterns, large bending angles (≈500°), excellent weight‐to‐lift ratios (≈60), and moderate response time (≈5 min). Thus, nanoassembly topology‐dependent and shape‐programmable intelligent materials are successfully developed for biomimetic 4D printing. [ABSTRACT FROM AUTHOR]

The mineralization of type I collagen is a biological process occurring in vertebrates by which some hard tissues such as bone and dentin are constructed. Due to the extensive clinical needs for bone defect repair and remineralization of mineral‐depleted dentin, biomimetic mineralization of collagen is attracting more and more interests. Synthetic analogs of noncollagenous proteins are necessary for directing the in vitro mineralization. In this paper, the function and mechanism of poly(acrylic acid) (PAA) in regulating the mineralization, especially intrafibrillar mineralization (IM) of collagen are reviewed. As two mineralization patterns (extrafibrillar and intrafibrillar) co‐exist in natural hard tissues, differences between them in terms of microstructure, biodegradation, cytocompatibility, osteoinduction in vitro, and performance in vivo are systematically compared. Then the roles of PAA in biomimetic collagen IM within one‐analog and two‐analog systems are discussed, respectively. Moreover, mineralization of some self‐mineralizable collagen matrices is described. Due to the interactions between collagen and PAA play a crucial role in the processes of collagen mineralization, some reference researches are also provided involving the collagen/PAA interactions in some other fields. Finally, this review is ended with an outlook for future potential improvements based on the collection of existing bottlenecks in this field. [ABSTRACT FROM AUTHOR]

In recent years, hydrogels have attracted extensive attention in smart sensing owing to their biocompatibility and high elasticity. However, it is still a challenge to develop hydrogels with excellent multiple responsiveness for smart wearable sensors. In this paper, a facile synthesis of carbon quantum dots (CQDs)‐doped cross‐linked chitosan quaternary/carboxymethylcellulose hydrogels (CCCDs) is presented. Designing of dual network hydrogels decorated with CQDs provides abundant crosslinking and improves the mechanical properties of the hydrogels. The hydrogel‐based strain sensor exhibits excellent sensitivity (gauge factor: 9.88), linearity (R2: 0.97), stretchable ability (stress: 0.67 MPa; strain: 404%), good cyclicity, and durability. The luminescent properties are endowed by the CQDs further broaden the application of hydrogels for realizing flexible electronics. More interestingly, the strain sensor based on CCCDs hydrogel demonstrates photo responsiveness (ΔR/R0≈20%) and pH responsiveness (pH range ≈4–7) performance. CCCDs hydrogels can be used for gesture recognition and light sensing switch. As a proof‐of‐concept, a smart wearable sensor is designed for monitoring human activities and detecting pH variation in human sweat during exercise. This study reveals new possibilities for further applications in wearable health monitoring. [ABSTRACT FROM AUTHOR]

The charge carrier mobility of organic field‐effect transistors (OFETs) has been remarkably improved through several engineering approaches and techniques by targeting pivotal parts. Herein, an ultrathin perovskite channel layer that boosts the field‐effect mobility of conjugated polymer OFETs by forming perovskite‐conjugated polymer hybrid semiconducting channel is introduced. The optimized lead‐iodide‐based perovskite‐conjugated polymer hybrid channel transistors show enhanced hole mobility of over 4 cm2 V–1 s–1 (average = 2.10 cm2 V–1 s–1) with high reproducibility using a benchmark poly(3‐hexylthiophene) (P3HT) polymer and employing high‐k fluorinated polymer dielectrics. A significant hole carrier mobility enhancement of ≈200–400% in benzo[1,2‐b:4,5:b′]dithiophene (BDT)‐based conjugated polymers is also demonstrated by exploring certain interactive groups with perovskite. This significant enhancement in the transistor performance is attributed to the increased charge carrier density in the hybrid semiconducting channel and the perovskite–polymer interactions. The findings of this paper demonstrate an exceptional engineering approach for carrier mobility enhancement in hybrid perovskite‐conjugated‐polymer‐based electronic devices. [ABSTRACT FROM AUTHOR]

A facile and clean strategy for synthesizing unimodal polymethacrylates with narrow dispersity (Đ < 1.10) is successfully developed by a near‐infrared (NIR) light‐emitting diode (LED) light (λmax = 740 nm)‐controlled in situ bromine–iodine transformation reversible‐deactivation radical polymerization system without the use of NIR dyes and expensive catalysts. In this system, alkyl iodide ethyl α‐iodophenylacetate (EIPA) initiator is generated in situ by the nucleophilic substitution reaction between an alkyl bromide compound ethyl α‐bromophenylacetate and sodium iodide (NaI). At the same time, excessive NaI is also acted as a highly active catalyst by forming halogen bonds with terminal iodine of the polymer chains in this system to make it capable of precisely synthesizing polymethacrylates with narrow dispersities (Đ = 1.03–1.10). In addition, the strong penetration ability of NIR LED light is illustrated by the successful polymerization even through 11 pieces of A4 paper. [ABSTRACT FROM AUTHOR]

Poly(ionic liquid) (PIL)‐based porous membranes are extensively investigated as soft polymer actuators. While PILs have shown significant advancements in membrane fabrication and stabilization of metal nanoparticles (MNPs), research on integrating MNPs into porous membranes to achieve actuation behavior under multiple stimuli is limited. Herein, this work presents a new paradigm for designing a porous PIL‐polyacrylic acid (PAA) membrane with a distinct MNP gradient via a top‐bottom diffusion approach involving a metal salt precursor solution and NaBH4 as a reducing agent. The strong binding sites provided by PILs, combined with the gradient distribution of ‐COO− groups across the membrane cross‐section, play a significant role in controlling the MNPs' gradient distribution. Interestingly, the MNPs within the membrane display excellent catalytic activity in exothermic reactions such as H2O2 decomposition, dissipating uneven heat that quickly permeates the membrane network. This induces asymmetrical swelling of polymer chains, resulting in rapid membrane bending. Furthermore, such MNP‐loaded membrane could serve as a portable test paper for visually monitoring H2O2. This advancement paves the way for the development of intricate smart actuation materials and expands their practical applications in various real‐life scenarios. [ABSTRACT FROM AUTHOR]

Even though electrospinning is getting more and more attention, the preparation of 3D nanofibrous meshes is still a big challenge that limits the application of electrospun materials, especially in tissue engineering. To overcome this problem, several solutions are introduced but most of them focus on the postprocessing of the electrospun meshes. This paper presents a straightforward novel method that utilizes the joint effect of the addition of CaCl2 and the relative environmental humidity (RH), which can induce the random 3D formation of polysuccinimide (PSI) electrospun fibers with different such as wrinkled or ribbon‐like structures. Although the effect of humidity and inorganic salt additives on the micro and macrostructure of electrospun fibers is known, the connection between the two in this manner has never been presented. To investigate the effect, fibers with different PSI and CaCl2 concentrations at different humidity RH levels are prepared, and their microstructure is visualized with high‐resolution scanning electron microscopy (SEM). To reveal the nature of the interaction between the polymer and the CaCl2, Fourier‐transformed infrared (FTIR), X‐ray diffraction (XRD), and thermogravimetry (TGA) measurements are carried out and 3D nanofibrous structures are obtained. [ABSTRACT FROM AUTHOR]

Covalent adaptable networks (CANs) possess multiple functions including reprocessing (or recyclability), self‐healing, welding, shape shifting, 3D printing, etc., due to the network rearrangement from dynamic bonds, and favorable performance from their cross‐linked feature, and they are supposed to be as sustainable alternatives to thermosets. However, the thermal and mechanical properties, and stability of CANs are often sacrificed for rapid network rearrangement. In this paper, fast‐reprocessing CANs with high performance are facilely constructed by in situ polymerization and dynamic cross‐linking of styrene (St), maleic anhydride (MA), and acetal diol (BHAD). The rigid and hydrophobic polymer backbone endow the materials with high glass transition temperatures, mechanical performance, and water resistance. Besides, carboxylic group‐catalyzed dual dynamic ester and acetal‐based networks exhibit faster stress relaxation and realize extrusion reprocessing. This work provides an ingenious and simple strategy of construction of CANs combining rapid network rearrangement and excellent comprehensive performance, which is beneficial for the application of CANs. [ABSTRACT FROM AUTHOR]