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Semitransparent organic solar cells (ST-OSCs) are promising candidates for applications in building-integrated photovoltaics (BIPV) as windows and facades. The challenge to achieve highly efficient ST-OSCs is the trade-off between power conversion efficiency (PCE) and average visible transmittance (AVT). Herein, solution-processed ST-OSCs are demonstrated on the basis a polymer donor, PM6, and a small molecule acceptor, Y6; lowering the visible-absorbing PM6 contents in blends could increase AVT and maintain PCE. Additionally, conductive polymer PEDOT:PSS is used as the top electrode due to its high transparency, good conductivity, and solution processability. Efficient ST-OSCs with 20 wt % PM6 achieve high PCE of 7.46% and AVT of 36.4%. The light utilization efficiency (LUE) of 2.72% is among the best reported values for solution-processed ST-OSCs. This work provides a straightforward approach for solution-processed ST-OSCs by combining a low fraction of visible-wavelength-selective polymer donors with near-infrared nonfullerene acceptors to achieve high PCE and AVT simultaneously. Funding agencies: Knut and Alice Wallenberg foundationKnut & Alice Wallenberg Foundation [2016.0059]; Swedish Government Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [200900971]; China Scholarship Council (CSC)China Scholarship Council [201708370115]

Radiative cooling passively removes heat from objects via emission of thermal radiation to cold space. Suitable radiative cooling materials absorb infrared light while they avoid solar heating by either reflecting or transmitting solar radiation, depending on the application. Here, we demonstrate a reflective radiative cooler and a transparent radiative cooler solely based on cellulose derivatives manufactured via electrospinning and casting, respectively. By modifying the microstructure of cellulose materials, we control the solar light interaction from highly reflective (> 90%, porous structure) to highly transparent (approximate to 90%, homogenous structure). Both cellulose materials show high thermal emissivity and minimal solar absorption, making them suitable for daytime radiative cooling. Used as coatings on silicon samples exposed to sun light at daytime, the reflective and transparent cellulose coolers could passively reduce sample temperatures by up to 15 degrees C and 5 degrees C, respectively. Funding Agencies|Linkoping University

Double-layer solid polymer electrolytes (DLSPEs) comprising one layer that is stable toward lithium metal and one which is stable against a high-voltage cathode are commonly suggested as a promising strategy to achieve high-energy-density lithium batteries. Through in-depth EIS analysis, it is here concluded that the polymer–polymer interface is the primary contributor to electrolyte resistance in such DLSPEs consisting of polyether-, polyester-, or polycarbonate-bad SPEs. In comparison to the bulk ionic resistance, the polymer–polymer interface resistance is approximately 10-fold higher. Nevertheless, the interfacial resistance was successfully lowered by doubling the salt concentration from 25 to 50 wt % LiTFSI owing to improved miscibility at the interface of the two polymer layers.

Diketopyrrolopyrroles (DPP) have been recognized as a promising acceptor unit for construction of semiconducting donor-acceptor (D-A) polymers, which are typically flanked by spacers such as thiophene rings via a carbon-carbon single bond formation. It may suffer from a decrease in the coplanarity of the molecules especially when bulky side chains are installed. In this work, the two N atoms in the DPP unit are further fused with C-3 of the two flanking thiophene rings, yielding a p-expanded, very planar fused-ring building block (DPPFu). A novel DPPFu-based D-A copolymer (PBDTT-DPPFu) was successfully synthesized, consisting of a benzo[1,2-b:4,5-b]dithiophene (BDTT) unit as a donor and a DPPFu unit as an acceptor. For comparison, the unfused DPP-based counterpart PBDTT-DPP was also synthesized. Two dodecyl alkyl chains were attached to thiophene rings of DPP moieties to ensure good solubility of the DPPFu-based polymer. The influence of the ring-fusion effect on their structure, photophysical properties, electronic properties, molecular packing, and charge transport properties is investigated. Ring-fusion enhances the intermolecular interactions of PBDTT-DPPFu polymer chains as indicated by density functional theory calculation and analysis of electrostatic potential and van der Waals potential and results in significantly improved molecular packing for both the in-plane and out-of-plane directions as suggested by X-ray measurements. Finally, we correlate the molecular packing to the device performance by fabricating field-effect transistors based on these two polymers. The charge carrier mobility of the ring-fused polymer PBDTT-DPPFu is significantly higher as compared to the PBDTT-DPP polymer without ring-fusion, although PBDTT-DPPFu exhibited a much lower number-average molecular weight of 17 kDa as compared to PBDTT-DPP with a molecular weight of 108 kDa. The results from our comparative study provide a robust way to increase the interchain interaction by ring-fusion-promoted coplanarity. Funding Agencies|Swedish Research CouncilSwedish Research CouncilEuropean Commission [2015-04853, 2016-06146, 2019-04683]; Swedish Research Council FormasSwedish Research CouncilSwedish Research Council Formas; NSFCNational Natural Science Foundation of China (NSFC) [21504006, 21534003, 11272093]; Knut and Alice Wallenberg FoundationKnut & Alice Wallenberg Foundation [2017.0186, 2016.0059]; Swedish Foundation for Strategic ResearchSwedish Foundation for Strategic Research; China Scholarship CouncilChina Scholarship Council [201908440047]; Guangzhou Municipal Science and Technology Bureau [201804010501, 201904010381, 202002030362]; Department of Education of Guangdong ProvinceNational Natural Science Foundation of Guangdong Province [2018GKTSCX041, 2017GKQNCX005]; Department of Science and Technology of Guangdong Province [2016A010103046]; Open Fund of the State Key Laboratory of Luminescent Materials and Devices (South China University of Technology) [2020-skllmd-07]; Natural Science Foundation of Hunan ProvinceNatural Science Foundation of Hunan Province [2018JJ3098]; Office of Science, Office of Basic Energy Sciences, of the U.S. Department of EnergyUnited States Department of Energy (DOE) [DE-AC02-05CH11231]

Semiconducting polymers that feature thermally activated delayed fluorescence (TADF) can deliver a much desired combination of high-efficiency and metal-free electroluminescence and cost-efficient solution-based fabrication. A TADF polymer is thus a very good fit for the emitting compound in light-emitting electrochemical cells (LECs) because the commonly employed air-stabile and few-layer LEC architecture is well suited for such solution-based fabrication. Herein we report on the first LEC device based on a TADF polymer as the emitting species, which delivers a luminance of 96 cd m–2 at 4 V and a current efficacy of 1.4 cd A–1 and >600 cd m–2 at 6 V, which is competitive with the performance of multilayer organic light-emitting diodes based on the same TADF polymer. We further utilize the established sensitivity of the emission of the TADF polymer to its environment to draw conclusions on the exciton populations in host-guest and host-free TADF LEC devices. Originally included in thesis in manuscript form.

Highly porous, strong aerogels with anisotropicstructural properties are of great interest for multifunctionalmaterials for applications including insulators in buildings,filters for oil cleanup, electrical storage devices,etc. Contem-porary aerogels are mostly extracted from fossil resources andsynthesized from bottom-up techniques, often requiring addi-tional strategies to obtain high anisotropy. In this work, auniversal approach to prepare porous, strong, anisotropicaerogels is presented through exploiting the natural hierarchicaland anisotropic structure of wood. The preparation comprisesnanoscale removal of lignin, followed by dissolution−regener-ation of nanofibers, leading to enhanced cell wall porosity with nanofibrillated networks occupying the pore space in thecellular wood structure. The aerogels retain structural anisotropy of natural wood, exhibit specific surface areas up to 247 m2/g, and show high compression strength at 95% porosity. This is a record specific area value for wood aerogels/foams and evenhigher than most cellulose-based aerogels for its assigned strength. The aerogel can serve as a platform for multifunctionalcomposites including scaffolds for catalysis, gas separation, or liquid purification due to its porous matrix or as binder-freeelectrodes in electronics. To demonstrate the multifunctionality, the aerogels are successfully decorated with metalnanoparticles (Ag) and metal oxide nanoparticles (TiO2)byin situsynthesis, coated by the conductive polymer(PEDOT:PSS), and carbonized to yield conductive aerogels. This approach is found to be a universal way to prepare highlyporous anisotropic aerogels. QC 20200918

Due to the mechanism with which solid polymer electrolytes use to conduct ions, these materials are generally more suitable for high-temperature applications where the ionic conductivity is sufficient and where liquid electrolytes show insufficient stability. To enable high-temperature cycling of polymer electrolytes, the mechanical stability has to be improved. Herein, we report successful long-term cycling of a solid polyester-polycarbonate - poly(epsilon-caprolactone-co-trimethylene carbonate) (poly(CL-co-TMC)) - electrolyte cross-linked through the addition of multifunctional acrylates and the use of UV-irradiation, allowing stable cycling of cells for more than 100 cycles at 80 degrees C, with good rate capabilities (0.2 mA cm(-2)) and Coulombic efficiencies exceeding 99 %. Both the mechanical properties and the ionic conductivity of the mechanically stabilized poly(CL-co-TMC) were investigated and optimized to reduce the frequency dependence of the moduli while still achieving an acceptable ionic conductivity at elevated temperature. These results indicate that the poly(CL-co-TMC) system can straight-forwardly be modified to allow for higher-temperature applications.

Waste tire rubber has been incorporated into asphalt modification for decades due to its various benefits. There are two main mechanisms during bitumen–rubber interaction: rubber swelling and chemical degradation. This study surveys these two processes from the viewpoint of polymer science. The kinetics of rubber dissolution and thermodynamics of rubber swelling are discussed to provide a fundamental understanding of the interaction process and to demonstrate how optimisation of material selection and processing procedures can lead to the desired binder properties. Factors including the interaction conditions and raw material characteristics are analysed based on the previous theories and compared with experimental results. © 2020, © 2020 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.

The interphase properties in nanocomposites indicate the interaction between filler and matrix, which is dependent on the preparation method, shape, and size of filler and the chemical interaction between two phases. Local chemical environment in polymer matrix give rise to the different dielectric properties compared to that of bulk material. These properties allow the understanding of their effects on the dielectric properties and glass transition (T-g) of the nanocomposites. In this study, interphase power law model was used to predict the interphase properties based on the experimental dielectric constant of polyimide (PI) with BaTiO3, TiO2, and ZrO2 nanocomposites. They were prepared via in situ polymerization of PI whose dielectric constant were increased at interphase filler volume fraction of BaTiO3, TiO2, and ZrO2 at 3.8, 2.05, and 1.7, respectively. These results indicate that PI/ceramics nanocomposites had poor dispersion and weak interphase interaction between the filler and the matrix, as an evidence of scanning electron microscopy and Fourier transform infrared spectroscopy results. However, PI incorporated with high aspect ratio of BaTiO3 nanofiber shows better dispersion than nanocomposites of TiO2 and ZrO2 filled PI; therefore provide higher dielectric constant and T-g. Funding Agencies|AUN/SEED-Net [6050315]; RU (I) [814242]

Engineering low-band-gap -conjugated polymers is a growing area in basic and applied research. The main synthetic challenge lies in the solubility of the starting materials, which precludes advancements in the field. Here, we report an on-surface synthesis protocol to overcome such difficulties and produce poly(p-anthracene ethynylene) molecular wires on Au(111). To this aim, a quinoid anthracene precursor with =CBr2 moieties is deposited and annealed to 400K, resulting in anthracene-based polymers. High-resolution nc-AFM measurements confirm the nature of the ethynylene-bridge bond between the anthracene moieties. Theoretical simulations illustrate the mechanism of the chemical reaction, highlighting three major steps: dehalogenation, diffusion of surface-stabilized carbenes, and homocoupling, which enables the formation of an ethynylene bridge. Our results introduce a novel chemical protocol to design -conjugated polymers based on oligoacene precursors and pave new avenues for advancing the emerging field of on-surface synthesis. Funding Agencies|Comunidad de Madrid [Y2018/NMT-4783, S2013/MIT-3007, S2018/NMT]; European Research Council [ERC-320441-Chirallcarbon, ERC-766555-ELECNANO]; Spanish Ramon y Cajal programme [RYC-2012-11133]; MINECO of Spain [FIS 2015-67287-P, CTQ2017-83531-R, CTQ2016-81911-REDT]; Severo Ochoa Programme for Centers of Excellence in RD (MINECO) [SEV-2016-0686]; Praemium Academie of the Academy of Science of the Czech Republic [MEYS LM2015087, GACR 18-09914S]; Operational Programme Research, Development, and Education - European Structural and Investment Funds; Czech Ministry of Education, Youth, and Sports [CZ.02.1.01/0.0/0.0/16019/0000754]; Czech Science Foundation [19-27454X]; Swedish Research Council [642-2013-2080]; Swedish Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009 00971]

Entangled polymers are deformed by a strong shear flow. The shape of the polymer, called the form factor, is measured by small angle neutron scattering. However, the real-space molecular structure is not directly available from the reciprocal-space data, due to the phase problem. Instead, the data has to be fitted with a theoretical model of the molecule. We approximate the unknown structure using piecewise straight segments, from which we derive an analytical form factor. We fit it to our data on a semi-dilute entangled polystyrene solution under in situ shear flow. The character of the deformation is shown to lie between that of a single ideal chain (viscous) and a cross-linked network (elastic rubber). Furthermore, we use the fitted structure to estimate the mechanical stress, and find a fairly good agreement with rheology literature.

In this study, laser-induced in situ amorphization (i.e., amorphization inside the final dosage form) of the model drug celecoxib (CCX) with six different polymers was investigated. The drug–polymer combinations were studied with regard to the influence of (i) the physicochemical properties of the polymer, e.g., the glass transition temperature (Tg) and (ii) the drug–polymer solubility on the rate and degree of in situ drug amorphization. Compacts were prepared containing 30 wt% CCX, 69.25 wt% polymer, 0.5 wt% lubricant, and 0.25 wt% plasmonic nanoparticles (PNs) and exposed to near-infrared laser radiation. Upon exposure to laser radiation, the PNs generated heat, which allowed drug dissolution into the polymer at temperatures above its Tg, yielding an amorphous solid dispersion. It was found that in situ drug amorphization was possible for drug–polymer combinations, where the temperature reached during exposure to laser radiation was above the onset temperature for a dissolution process of the drug into the polymer, i.e., TDStart. The findings of this study showed that the concept of laser-induced in situ drug amorphization is applicable to a range of polymers if the drug is soluble in the polymer and temperatures during the process are above TDStart.

The sustainable development of engineering biocomposites has been limited due to a lack of bio‐based monomers combining favorable processing with high performance. Here, the authors report a novel and fully bio‐based transparent wood biocomposite based on green synthesis of a new limonene acrylate monomer from renewable resources. The monomer is impregnated and readily polymerized in a delignified, succinylated wood substrate to form optically transparent biocomposites. The chemical structure of the limonene acrylate enables diffusion into the cell wall, and the polymer phase is both refractive index‐matched and covalently linked to the wood substrate. This results in nanostructured biocomposites combining an excellent optical transmittance of 90% at 1.2 mm thickness and a remarkably low haze of 30%, with a high mechanical performance (strength 174 MPa, Young's modulus 17 GPa). Bio‐based transparent wood holds great potential towards the development of sustainable wood nanotechnologies for structural applications, where transparency and mechanical performance are combined., A fully bio‐based transparent wood biocomposite is prepared by impregnation and polymerization of a novel, green limonene acrylate monomer into a wood substrate. Succinylation of the delignified wood substrate using succinic anhydride results in a nanostructured and mechanically strong biocomposite with a tailored interface. The optically transparent wood biocomposite combines high transmittance and low haze.

Enzymes immobilized on synthetic polyethylene terephthalate (PET) textile surface by resource‐efficient inkjet printing technology can promote developments for various novel applications. Synthetic fabrics often require adequate pretreatments to facilitate such printing process. This work discusses PET–woven fabric pretreatment routes to improve wettability by alkaline, enzymatic, and plasma processes for effective printing of lysozyme using an industrial piezoelectric printhead. Results indicate that all pretreated samples contain a similar amount of enzymes upon printing. Plasma treated fabrics show relatively more hydrophilic surface characteristics, better protein binding stability, and lower retained activity. Alkali and cutinase‐treated samples possess relatively higher activity due to the greater amount of enzyme desorption to substrate solution. Depending on respective enzyme‐binding stability, a combination of a well-pretreated surface and inkjet as preferential placement technology, the approach of this study can be used as a facile enzyme immobilization method for suitable applications, for example, controlled‐release and bio‐sensing. Correction to article published 23 November 2021: https://doi.org/10.1002/admi.202101935

The purpose of this study was to investigate the influence of aging on the properties of high-density polyethylene (HDPE) reinforced with multi-wall carbon nanotubes (MWCNTs). Nanocomposites were prepared with nanotubes at 0, 1, 3, and 5 wt%. The long-term durability of the prepared materials was evaluated by thermo-oxidative aging test. Test bodies were aged at 110°C for up to 10 weeks. The nanocomposites were characterized by differential scanning calometry, thermogravimetric analysis (TGA), 13C-NMR, elongation at break, and transmission electron microscopy. The aging mainly occurred on the surface of the samples and the neat HDPE showed a strong yellowing after the aging. A strong reduction in elongation at break was seen. For neat HDPE, the elongation at break was reduced from roughly 1400–25%. When HDPE was reinforced with the nanotubes, the reduction was less dramatic

The limited ionic conductivity is the main issue for the application of solid-state ionic conductors. In this work, we have shown that increasing the ferroelectric phase content in a polymer matrix could enhance the molar ionic conductivity of the incorporated ionic liquid by two orders of magnitude compared to the original films with the same composition. The ferroelectric polymer fiber mats were prepared through electrospinning to induce the ferroelectric phase that ensure the polarization of the dipoles. After analyzing the ferroelectric phase content and polarization of the fiber mats and films containing different ion concentration with FTIR spectroscopy and piezoelectric characterization, a detailed mechanism explaining the improved conductivity in the ferroelectric fiber mats was proposed. Benefiting from the good flexibility, improved ionic conductivity and high temperature coefficient of the fiber mats, we fabricated an organic ionic thermistor. The temperature tracking and mapping function of the ionic thermistor was demonstrated by using two devices with 4 and 16 pixels. Funding Agencies|Swedish Research Council VRSwedish Research Council [2016-05990, 2018-04037]; Wallenberg Wood Science Center; Advanced Functional Materials Center at Linkoping University [2009-00971]; Knut and Alice Wallenberg FoundationKnut & Alice Wallenberg Foundation

The efficiency of bulk heterojunction (BHJ) based organic solar cells is highly dependent on the morphology of the blend film, which is a result of a fine interplay between donor, acceptor, and solvent during the film drying. In this work, a versatile set-up of in situ spectroscopies is used to follow the morphology evolution during blade coating of three iconic BHJ systems, including polymer:fullerene, polymer:nonfullerene small molecule, and polymer:polymer. the drying and photoluminescence quenching dynamics are systematically study during the film formation of both pristine and BHJ films, which indicate that the component with higher molecular weight dominates the blend film formation and the final morphology. Furthermore, Time-resolved photoluminescence, which is employed for the first time as an in situ method for such drying studies, allows to quantitatively determine the extent of dynamic and static quenching, as well as the relative change of quantum yield during film formation. This work contributes to a fundamental understanding of microstructure formation during the processing of different blend films. The presented setup is considered to be an important tool for the future development of blend inks for solution-cast organic or hybrid electronics. Funding Agencies|Knut and Alice Wallenberg Foundation through the project "Mastering Morphology for Solutionborne Electronics" [2016.0059]; Wallenberg Scholar grant from the Knut and Alice Wallenberg Foundation; Swedish Government Strategic Research Area in Material Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [200900971]; Swedish Research CouncilSwedish Research CouncilEuropean Commission [2017-04123]; China Scholarship CouncilChina Scholarship Council

Anthracene is a highly valuable building block for luminescent conjugated polymers, particularly when a large singlet-triplet energy gap (Delta E-ST) is desired. Unfortunately, the extended pi system of anthracene imparts a strong tendency for polymer aggregation, resulting in detrimental effects on its solid state photophysics. A large decrease in photoluminescence quantum yield (PLQY, phi(F)) on going from solution to the solid state is especially common, represented in terms of a low phi(R) (phi(R) = phi(F film)/phi(F sol.)). Significant and undesirable red-shifting of fluorescence in the solid state is also typical due to processes such as excimer formation. In this work a series of alkylene-encapsulated conjugated anthracene polymers is developed to overcome these challenging problems. We demonstrate a promising material which displays a good solid state PLQY that is effectively unchanged compared to solution measurements (phi(R) similar to 1, phi(F film) similar to 40%), alongside an identical PL 0-0 transition wavelength in solution and thin film. Such a direct transfer of luminescence properties from solution to the solid state is remarkable for a conjugated polymer and completely unprecedented for one based on anthracene.

Development of functional and stable solid polymer electrolytes SPEs for battery applications is an important step towards both safer batteries and for the realization of lithium based or anode less batteries. The interface between the lithium and the solid polymer electrolyte is one of the bottlenecks, where severe degradation is expected. Here, the stability of three different SPEs poly ethylene oxide PEO , poly amp; 949; caprolactone PCL and poly trimethylene carbonate PTMC together with lithium bis trifluoromethanesulfonyl imide LiTFSI salt, is investigated after they have been exposed to lithium metal under UHV conditions. Degradation compounds, e.g. Li O R, LiF and LixSyOz, are identified for all SPEs using soft X ray photoelectron spectroscopy. A competing degradation between polymer and salt is identified in the outermost surface region lt;7 nm , and is dependent on the polymer host. PTMC LiTFSI shows the most severe decomposition of both polymer and salt followed by PCL LiTFSI and PEO LiTFSI. In addition, the movement of lithium species through the decomposed interface shows large variation depending on the polymer electrolyte system

Removal of contaminants from wastewater is one key element for the development of sustainable society. Here, innovative “all-lignocellulose” derived photo-curable hydrogel nanocomposites based on methacrylated carboxymethyl cellulose (M-CMC) and lignosulfonate-derived carbonaceous products were successfully designed. The carbon products were synthesized by microwave-assisted hydrothermal carbonization (MAHC), followed by oxidation and methacrylation. This yielded nano-graphene oxide (nGO) and methacrylated nGO (M-nGO). The structure of the carbon products was confirmed by several spectroscopic techniques. The photo-curing process, mechanical properties, swelling degree, adsorption efficiency towards cationic contaminants and recycling efficiency of the produced hydrogel nanocomposites containing different amounts of nGO or M-nGO were evaluated. Rapid photo-curing was demonstrated for all studied compositions. However, the shielding effect caused by the addition of aromatic nGO increased the time required for reaching gel point (8.5–19.5 s, instead of 4.8 s for pure M-CMC). This was partially compensated by the addition of M-nGO, that could participate in the photo-curing process. The photo-cured nanocomposites, M-CMC/nGO and M-CMC/M-nGO, demonstrated good mechanical properties, extremely high swelling degrees, outstanding adsorption capacity (up to 350 and 145 mg/g for MB and Cu(II) adsorption, respectively) and very good recyclability for at least 3 cycles. The designed “all-lignocellulose” derived hydrogel nanocomposites are, thus, promising candidates for wastewater purification to ensure access to clean water. © 2020 The Authors QC 20210105

An important factor in the development of sodium-ion batteries (SIBs) is the use of cheap and sustainable materials. Sodium lignosulfonate, a lignin derivative, is demonstrated here as an attractive, “green”, water-soluble, and potentially cost-effective binder for use in hard carbon anodes for SIBs. A comparison of its battery cycling performance is made against other binders including sodium carboxymethyl cellulose and lignin, obtained from the kraft process, as well as sodium alginate, derived from algae. Apart from lignin, which requires processing in N-methyl-2-pyrrolidone, the other three binders are water-soluble. Lignosulfonate shows comparable or better performance, with high capacity retention and stability, when using 1 M NaPF6 in propylene carbonate or ethylene carbonate:diethyl carbonate electrolytes for both half- and full-cells (against a Prussian white cathode). Further improvements are observed when including styrene-butadiene rubber as a co-binder. X-ray photoelectron spectroscopy demonstrates similar solid electrolyte interphase compositions after the initial sodium insertion for both lignosulfonate and carboxymethyl cellulose binders. However, after subsequent cycling, the surface layer composition and thickness are found to be dependent on the binder. For the lignosulfonate-based electrode, the layer appears thicker but comprises a smaller fraction of carbon–oxygen species.

A composite electrolyte based on a garnet electrolyte (LLZO) and polyester-based co-polymer (80:20 epsilon-caprolactone (CL)-trimethylene carbonate, PCL-PTMC with LiTFSI salt) is prepared. Integrating the merits of both ceramic and co-polymer electrolytes is expected to address the poor ionic conductivity and high interfacial resistance in solid-state lithium-ion batteries. The composite electrolyte with 80 wt % LLZO and 20 wt % polymer (PCL-PTMC and lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) at 72:28 wt %) exhibited a Li-ion conductivity of 1.31 X 10(-4) S/cm and a transference number (t(Li+)) of 0.84 at 60 degrees C, notably higher than those of the pristine PCL-PTMC electrolyte. The prepared composite electrolyte also exhibited an electrochemical stability of up to 5.4 V vs Li+/Li. The interface between the composite electrolyte and a LiFePO4 (LFP) cathode was also improved by direct incorporation of the polymer electrolyte as a binder in the cathode coating. A Li/composite electrolyte/LFP solid-state cell provided a discharge capacity of ca. 140 mAh/g and suitable cycling stability at 55 degrees C after 40 cycles. This study clearly suggests that this type of amorphous polyester-based polymers can be applied in polymer-in-ceramic composite electrolytes for the realization of advanced all-solid-state lithium-ion batteries.

We study composites of cellulose nanocrystals (CNCs) in an ionomer matrix of poly(ethylene-stat-sodium acrylate) and find that direct cellulose/cellulose interactions in the composite are not a requirement for achieving reinforcement. While isotropic composites only show a slightly enhanced stiffness compared to the neat ionomer, a more substantial increase in Youngs modulus by a factor of up to 5 is achieved by uniaxial alignment of the composites through melt spinning. The orientation of CNC in melt-spun composites reduces the probability of cellulose/cellulose interactions, which suggests that cellulose/polymer interactions must be present that lead to the observed reinforcement. Molecular dynamics simulations confirm strong cellulose/polymer interactions in the form of ionic interactions as well as hydrogen bonding. These cellulose/polymer interactions facilitate efficient stress transfer, leading to the high reinforcing effect of CNC, while cellulose/cellulose interactions play a minor role in the mechanical response of the composite. Funding Agencies|Swedish Foundation for Strategic ResearchSwedish Foundation for Strategic Research [RMA15-0052]; Swedish Research Council FormasSwedish Research CouncilSwedish Research Council Formas [FR-2018/0010]; Treesearch; Chalmers University of Technology Foundation; Swedish Research CouncilSwedish Research CouncilEuropean Commission [2018-06487 RFI NanoSPAM]

Polymer-based ion exchange membranes (IEMs) are utilized for many applications such as in water desalination, energy storage, fuel cells and in electrophoretic drug delivery devices, exemplified by the organic electronic ion pump (OEIP). The bulk of current research is primarily focused on finding highly conductive and stable IEM materials. Even though great progress has been made, a lack of fundamental understanding of how specific polymer properties affect ionic transport capabilities still remains. This leads to uncertainty in how to proceed with synthetic approaches for designing better IEM materials. In this study, an investigation of the structure-property relationship between polymer size and ionic conductivity was performed by comparing a series of membranes, based on ionically charged hyperbranched polyglycerol of different polymer sizes. Observing an increase in ionic conductivity associated with increasing polymer size and greater electrolyte exclusion, indi-cating an ionic transportation phenomenon not exclusively based on membrane electrolyte uptake. These findings further our understanding of ion transport phenomena in semi-permeable membranes and indicate a strong starting point for future design and synthesis of IEM polymers to achieve broader capabilities for a variety of ion transport-based applications. Funding Agencies|Swiss Society for Biomaterials and Regenerative Medicine, SSB + RM; Swedish Foundation for Strategic ResearchSwedish Foundation for Strategic Research; Swedish Research CouncilSwedish Research CouncilEuropean Commission; European UnionEuropean Commission [834677]

Attaching hydrogels to soft internal tissues is crucial for the development of various biomedical devices. Tough sticky hydrogel patches present high adhesion, yet with lack of injectability and the need for treatment of contacting surface. On the contrary, injectable and photo-curable hydrogels are highly attractive owing to their ease of use, flexibility of filling any shape, and their minimally invasive character, compared to their conventional preformed counterparts. Despite recent advances in material developments, a hydrogel that exhibits both proper injectability and sufficient intrinsic adhesion is yet to be demonstrated. Herein, a paradigm shift is proposed toward the design of intrinsically adhesive networks for injectable and photo-curable hydrogels. The bioinspired design strategy not only provides strong adhesive contact, but also results in a wide window of physicochemical properties. The adhesive networks are based on a family of polymeric backbones where chains are modified to be intrinsically adhesive to host tissue and simultaneously form a hydrogel network via a hybrid cross-linking mechanism. With this strategy, adhesion is achieved through a controlled synergy between the interfacial chemistry and bulk mechanical properties. The functionalities of the bioadhesives are demonstrated for various applications, such as tissue adhesives, surgical sealants, or injectable scaffolds.

Dynamic control of structural colors across the visible spectrum with high brightness has proven to be a difficult challenge. Here, this is addressed with a tuneable reflective nano-optical cavity that uses an electroactive conducting polymer (poly(thieno[3,4-b]thiophene)) as spacer layer. Electrochemical doping and dedoping of the polymer spacer layer provides reversible tuning of the cavitys structural color throughout the entire visible range and beyond. Furthermore, the cavity provides high peak reflectance that varies only slightly between the reduced and oxidized states of the polymer. The results indicate that the polymer undergoes large reversible thickness changes upon redox tuning, aided by changes in optical properties and low visible absorption. The electroactive cavity concept may find particular use in reflective displays, by opening for tuneable monopixels that eliminate limitations in brightness of traditional subpixel-based systems. Funding Agencies|Swedish Foundation for Strategic ResearchSwedish Foundation for Strategic Research; Knut and Alice Wallenberg FoundationKnut & Alice Wallenberg Foundation; Swedish Research Council (VR)Swedish Research Council; Wenner-Gren Foundations; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009 00971]

There is no molecular strategy for selectively increasing the Seebeck coefficient without reducing the electrical conductivity for organic thermoelectrics. Here, it is reported that the use of amphipathic side chains in an n-type donor-acceptor copolymer can selectively increase the Seebeck coefficient and thus increase the power factor by a factor of approximate to 5. The amphipathic side chain contains an alkyl chain segment as a spacer between the polymer backbone and an ethylene glycol type chain segment. The use of this alkyl spacer does not only reduce the energetic disorder in the conjugated polymer film but can also properly control the dopant sites away from the backbone, which minimizes the adverse influence of counterions. As confirmed by kinetic Monte Carlo simulations with the host-dopant distance as the only variable, a reduced Coulombic interaction resulting from a larger host-dopant distance contributes to a higher Seebeck coefficient for a given electrical conductivity. Finally, an optimized power factor of 18 mu W m(-1) K-2 is achieved in the doped polymer film. This work provides a facile molecular strategy for selectively improving the Seebeck coefficient and opens up a new route for optimizing the dopant location toward realizing better n-type polymeric thermoelectrics. Funding Agencies|STW/NWOTechnologiestichting STWNetherlands Organization for Scientific Research (NWO) [VIDI 13476]; China Scholarship CouncilChina Scholarship Council; Center for Information Technology of the University of Groningen; Swedish Research CouncilSwedish Research Council [2016-03979]; Olle Engkvists Stiftelse [204-0256]; Advanced Functional Materials center at LiU [2009 00971]; King Abdullah University of Science and Technology (KAUST) Office of Sponsored Research (OSR) [OSR-CRG2018-3737]; NWO Exact and Natural Sciences [2020/ENW/00852342]

Hard carbons are the most promising negative active materials for sodium ion storage. In this work, a simple synthesis approach is proposed to produce hard carbon microspheres (CMSs) (with a mean diameter of ~1.3 μm) from resorcinol-formaldehyde precursors produced via acid-catalyzed polycondensation reaction. Samples prepared at 1200, 1400, and 1500 oC showed different electrochemical behavior in terms of reversible capacity, initial coulombic efficiency (iCE), and the mechanism of sodium ion storage. The specific capacity contributions from the flat voltage profile (

Increasing the ionic conductivity has for decades been an overriding goal in the development of solid polymer electrolytes. According to fundamental theories on ion transport mechanisms in polymers, the ionic conductivity is strongly correlated to free volume and segmental mobility of the polymer for the conventional transport processes. Therefore, incorporating plasticizing side chains onto the main chain of the polymer host often appears as a clear-cut strategy to improve the ionic conductivity of the system through lowering of the glass transition temperature (T-g) This intended correlation between Tg and ionic conductivity is, however, not consistently observed in practice. The aim of this study is therefore to elucidate this interplay between segmental mobility and polymer structure in polymer electrolyte systems comprising plasticizing side chains. To this end, we utilize the synthetic versatility of the ion-conductive poly(trimethylene carbonate) (PTMC) platform. Two types of host polymers with side chains added to a PTMC backbone are employed, and the resulting electrolytes are investigated together with the side chain-free analogue both by experiment and with molecular dynamics (MD) simulations. The results show that while added side chains do indeed lead to a lower Tg, the total ionic conductivity is highest in the host matrix without side chains. It was seen in the MD simulations that while side chains promote ionic mobility associated with the polymer chain, the more efficient interchain hopping transport mechanism occurs with a higher probability in the system without side chains. This is connected to a significantly higher solvation site diversity for the Li+ ions in the side-chain-free system, providing better conduction paths. These results strongly indicate that the side chains in fact restrict the mobility of the Li+ ions in the polymer hosts.

A series of glycolated polythiophenes for use in organic electrochemical transistors (OECTs) is designed and synthesized, differing in the distribution of their ethylene glycol chains that are tethered to the conjugated backbone. While side chain redistribution does not have a significant impact on the optoelectronic properties of the polymers, this molecular engineering strategy strongly impacts the water uptake achieved in the polymers. By careful optimization of the water uptake in the polymer films, OECTs with unprecedented steady-state performances in terms of [mu C*] and current retentions up to 98% over 700 electrochemical switching cycles are developed. Funding Agencies|KAUSTKing Abdullah University of Science & Technology; King Abdullah University of Science and Technology Office of Sponsored Research (OSR) [OSR-2018-CARF/CCF-3079, OSR-2015-CRG4-2572, OSR-4106 CPF2019]; EC FP7 Project SC2 [610115]; EC H2020 [643791]; EPSRCEngineering & Physical Sciences Research Council (EPSRC) [EP/G037515/1, EP/M005143/1, EP/L016702/1]; Knut and Alice Wallenberg FoundationKnut & Alice Wallenberg Foundation; Wallenberg Wood Science Center [KAW 2018.0452]; Swedish Government Strategic Research Area in Materials Science on Advanced Functional Materials at Linkoping University [2009-00971]; TomKat Center for Sustainable Energy at Stanford University

We report a side group modification strategy to tailor the structure of a polymer of intrinsic microporosity (PIM-1). PIM-1 with an average of ∼50% of the repeat units converted to tetrazole is prepared, and a subsequent reaction then introduces three types of pseudo-ionic liquid tetrazole-like structures (PIM-1-ILx). The presence of pseudo-ionic liquid functional groups in the PIM-1 structure increases gas selectivities for O2/N2 and CO2/N2, while it decreases pure-gas permeabilities. The overall gas separation performance of PIM-1-ILx is close to the 2008 Robeson upper bound. Since the tetrazoles are versatile groups for building a wide variety of ionic liquids, the modification method can be expanded to explore a broad spectrum of functional groups.

Carbon-based adsorbents possess exceptional adsorption capability, making them an ideal platform for the remediation of environmental contaminants. Here, we demonstrate carbonized lignosulfonate (LS)-based porous nanocomposites with excellent adsorption performance towards heavy metal ions and cationic dye pollutants. Through microwave-assisted hydrothermal carbonization, a green approach was employed to carbonize lignosulfonate to carbon spheres. The LS-derived carbon spheres were then oxidized into nanographene oxide (nGO) carbon dots. A facile two-step procedure that involved the self-assembly of nGO and gelatin into a hydrogel precursor coupled with freeze-drying enabled the construction of three-dimensional (3D) free-standing porous composites without the use of organic solvents or chemical crosslinking agents. The favorable pore structure and abundance of surface functional groups on the nGO/gelatin porous composite proved to substantially facilitate the adsorption of Cu(II) in comparison to conventionally-used activated carbon. Further enhancement of adsorption performance was achieved by introducing additional surface functional groups through a non-covalent functionalization of the porous composite with lignosulfonate. The presence of negatively-charged sulfonate groups increased the Cu(II) equilibrium adsorption capacity (66 mg/g) by 24% in comparison to the non-functionalized nGO/gelatin counterpart. Both functionalized and non-functionalized composites exhibited significantly faster adsorption rates (40 min) compared to many graphene- or GO-based adsorbents reported in literature. In addition to the adsorption of heavy metal ions, the composites also demonstrated good adsorption capacity towards cationic dyes such as methylene blue. This paves the way for a high value-added application of lignin in environmental remediation and opens up new possibilities for the development of sustainable materials for adsorption and water purification.

In this work, we demonstrate all-polymer solar cells where all the layers are made from polymers. We use PEDOT:PSS as the semitransparent anode and polyethyleneimine modified PEDOT:PSS as the semitransparent cathode, both of which are slot-die printed on polyethylene terephthalate (PET). Active layers are deposited on the cathode and anode surfaces by spin coating separately. These layers are then joined through a roll-to-roll compatible lamination process. This results in a semitransparent and flexible solar cell. We have used two polymer-polymer systems and several combinations, and the highest power conversion efficiency (PCE) obtained is 2.3% with a mean transparency amp;gt;35% within the visible light range. By laminating a thin layer acceptor polymer to a thick polymer-polymer blend, we can improve the performance by reducing recombination, compared to laminating blend to blend, which is verified by the trap-limited charge transport, CELIV and electroluminescence. Funding Agencies|Swedish Energy Agency; Knut and Alice Wallenberg foundation (KAW); China Scholarship Council (CSC)

Solid polymer electrolytes (SPEs) are promising candidates for solid-state lithium-ion batteries. Potentially, they can be used with lithium metal anodes and high-voltage cathodes, provided that their electrochemical stability is sufficient. Thus far, the oxidative stability has largely been asserted based on results obtained with sweep voltammetry, which are often determined and reliant on arbitrary assessments that are highly dependent on the experimental conditions and do not take the interaction between the electrolyte and the electrode material into account. In this study, alternative techniques are introduced to address the pitfalls of sweep voltammetry for determining the oxidative stability of SPEs. Staircase voltammetry involves static conditions and eliminates the kinetic aspects of sweep voltammetry, and coupled with impedance spectroscopy provides information of changes in resistance and interphase layer formation. Synthetic charge–discharge profile voltammetry applies the real voltage profile of the active material of interest. The added effect of the electrode active material is investigated with a cut-off increase cell cycling method where the upper cut-off voltage during galvanostatic cycling is gradually increased. The feasibility of these techniques has been tested with both poly(ethylene oxide) and poly(trimethylene carbonate) combined with LiTFSI, thereby showing the applicability for several categories of SPEs.

Owing to changes in their chemistry and structure, polymers can be fabricated to demonstrate vastly different electrical conductivities over many orders of magnitude. At the high end of conductivity is the class of conducting polymers, which are ideal candidates for many applications in low-cost electronics. Here, we report the influence of the nature of the doping anion at high doping levels within the semi-metallic conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT) on its electronic transport properties. Hall effect measurements on a variety of PEDOT samples show that the choice of doping anion can lead to an order of magnitude enhancement in the charge carrier mobility > 3 cm2/Vs at conductivities approaching 3000 S/cm under ambient conditions. Grazing Incidence Wide Angle X-ray Scattering, Density Functional Theory calculations, and Molecular Dynamics simulations indicate that the chosen doping anion modifies the way PEDOT chains stack together. This link between structure and specific anion doping at high doping levels has ramifications for the fabrication of conducting polymer-based devices, The authors acknowledge the European Research Council (ERC-starting-grant 307596), the Swedish foundation for strategic research (project: “Nano-material and Scalable TE materials”), the Knut and Alice Wallenberg foundation (project “Power Paper” and “Tail of the Sun”), The Swedish Energy Agency (3833221), the Swedish Research Council via “Research Environment grant” on “Disposable paper fuel cells” (2016205990), and the Advanced Functional Materials Center at Linköping University. The authors thank Masatsugu Yamashita from the THz Sensing & Imaging Lab at RIKEN in Japan for conducting the THz reflectance spectroscopy experiments. D.R. Evans acknowledges the support of the Australian Research Council through the Future Fellowship scheme (FT160100300). J.W. Andreasen acknowledges the support of the European Research Council (ERC-consolidator-grant 681881). The computations were performed on resources provided by the Swedish National Infrastructure for Computing (SNIC) at NSC.

Poly(3,4-ethylenedioxythiophene) doped with poly(styrenesulfonate) (PEDOT:PSS) has been reported as a successful functional material in a broad variety of applications. One of the most important advantages of PEDOT:PSS is its water-solubility, which enables simple and environmental friendly manufacturing processes. Unfortunately, this also implies that pristine PEDOT:PSS films are unsuitable for applications in aqueous environments. To reach stability in polar solvents, (3-glycidyloxypropyl)trimethoxysilane (GOPS) is typically used to cross-link PEDOT:PSS. Although this strategy is widely used, its mechanism and effect on PEDOT:PSS performance have not been articulated yet. Here, we present a broad study that provides a better understanding of the effect of GOPS on the electrical and electronic properties of PEDOT:PSS. We show that the GOPS reacts with the sulfonic acid group of the excess PSS, causing a change in the PEDOT:PSS film morphology, while the oxidation level of PEDOT remains unaffected. This is at the origin of the observed conductivity changes. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2017, 55, 814–820

Currently, there are limited approaches to tailor 3D scaffolds cross-linked with a stable covalent C-C bond that does not require any catalysts or initiators. We present here the first hydrogels employing aldol condensation chemistry that exhibit exceptional physicochemical properties. We investigated the aldol-cross-linking chemistry using two types of aldehyde-modified hyaluronic acid (HA) derivatives, namely, an enolizable HA-aldehyde (HA-Eal) and a non-enolizable HA-aldehyde (HA-Nal). Hydrogels formed using HA-Eal demonstrate inferior cross-linking efficiency (due to intramolecular loop formation), when compared with hydrogels formed by mixing HA-Eal and HA-NaI leading to a cross-aldol product. The change in mechanical properties as a result of cross-linking at different pH values is determined using rheological measurements and is interpreted in terms of molecular weight between cross-links (Mc). The novel HA cross-aldol hydrogel demonstrate excellent hydrolytic stability and favorable mechanical properties but allow hyaluronidase-mediated enzymatic degradation. Interestingly, residual aldehyde functionality within the aldol product rendered the tissue-adhesive properties by bonding two bone tissues. The aldehyde functionality also facilitated facile post-synthetic modifications with nucleophilic reagents. Finally, we demonstrate that the novel hydrogel is biocompatible with encapsulated stem cells that show a linear rate of expansion in our 3-6 days of study.

The morphology of the active layer plays a crucial role in determining device performance and stability for organic solar cells. All-polymer solar cells (All-PSCs), showing robust and stable morphologies, have been proven to give better thermal stability than their fullerene counterparts. However, outstanding thermal stability is not always the case for polymer blends, and the limiting factors responsible for the poor thermal stability in some All-PSCs, and how to obtain higher efficiency without losing stability, still remain unclear. By studying the morphology of poly [2,3-bis (3-octyloxyphenyl) quinoxaline-5,8-diyl-alt-thiophene-2,5-diyl](TQ1)/poly[4,8-bis[5-(2-ethylhexyl)-2-thienyl]benzo[1,2-b:4,5-b&prime, ]dithiophene-alt-(4-(2-ethylhexyl)-3-fluorothieno[3,4-b]thiophene-)-2-carboxylate-2-6-diyl]] (PCE10)/PNDI-T10 blend systems, we found that the rearranged molecular packing structure and phase separation were mainly responsible for the poor thermal stability in devices containing PCE10. The TQ1/PNDI-T10 devices exhibited an improved PCE with a decreased &pi, &ndash, &pi, stacking distance after thermal annealing, PCE10/PNDI-T10 devices showed a better pristine PCE, however, thermal annealing induced the increased &pi, stacking distance and thus inferior hole conductivity, leading to a decreased PCE. Thus, a maximum PCE could be achieved in a TQ1/PCE10/PNDI-T10 (1/1/1) ternary system after thermal annealing resulting from their favorable molecular interaction and the trade-off of molecular packing structure variations between TQ1 and PCE10. This indicates that a route to efficient and thermal stable All-PSCs can be achieved in a ternary blend by using material with excellent pristine efficiency, combined with another material showing improved efficiency under thermal annealing.

Solid polymer electrolytes based on high-molecular-weight poly(trimethylene carbonate) (PTMC) in combination with NaFSI salt were investigated for application in sodium batteries. The polycarbonate host material proved to be able to dissolve large amounts of salt, at least up to a carbonate:Na+ ratio of 1:1. Combined DSC, conductivity, and FTIR data indicated the formation of a percolating network of salt clusters along with the transition to a percolation-type ion transport mechanism at the highest salt concentrations. While the highest total ionic conductivities were seen at the highest salt concentrations (up to a remarkable 5 x 10(-5) S cm(-1) at 25 degrees C at a 1:1 carbonate:Na+ ratio), the most stable battery performance was seen at a more moderate salt loading of 5:1 carbonate:Na+, reaching >80 cycles at a stable capacity of similar to 90 mAh g(-1) at 60 degrees C in a sodium metal/Prussian blue cell. The results highlight the importance of the choice of salt and salt concentration on electrolyte performance as well as demonstrate the potential of utilizing polycarbonate-based electrolytes in sodium-based energy storage systems.

Thin macroporous poly(vinyl alcohol) (PVA) hydrogels were produced by cross-linking of PVA in a semi-frozen state with glutaraldehyde (GA) on glass slides or in the wells of microtiter plates. The 100-130 mu m-thick gels were mechanically transferable, squamous translucent films with a high porosity of 7.2 +/- 0.3 mL/g dry PVA i.e. similar to larger cylindrical PVA monoliths of the same composition. Additional treatment of the gels with 1% GA increased the aldehyde group content from 0.7 to 2.4 mu mol/mL as estimated using dinitrophenylhydrazine (DNPH) reagent. Translucency of the gels allowed registration of UV-visible spectra of the DNP' ;Wined films. The catalytic activity of trypsin covalently immobilized on thin gels in the microtiter plates was estimated with chromogenic substrate directly in the wells, and indicated that the amount of protein immobilized was at least 0.34 mg/mL gel. Human immunoglobulin G (IgG) immobilized on thin gels at 0.1-10 mg/mL starting concentrations could be detected in a concentration-dependent manner due to recognition by anti-human rabbit IgG conjugated with peroxidase and photometric registration of the enzymatic activity. The results indicate good permeability of the hydrogel pores for macromolecular biospecific reagents and suggest applications of thin reactive PVA hydrogels in photometric analytical techniques.

The widespread use of renewable nanomaterials has been limited due to poor integration with conventional polymer matrices. Often, chemical and physical surface modifications are implemented to improve compatibility, however, this comes with environmental and economic cost. This work demonstrates that renewable nanomaterials, specifically cellulose nanocrystals (CNCs), can be utilized in their unmodified state and presents a simple and versatile, one-step method to produce polyamide/CNC nanocomposites with unique Janus-like properties. Nanocomposites in the form of films, fibers, and capsules are prepared by dispersing as-prepared CNCs in the aqueous phase prior to the interfacial polymerization of aromatic diamines and acyl chlorides. The diamines in the aqueous phase not only serve as a monomer for polymerization, but additionally, adsorb to and promote the incorporation of CNCs into the nanocomposite. Regardless of the architecture, CNCs are only present along the surface facing the aqueous phase, resulting in materials with unique, Janus-like wetting behavior and potential applications in filtration, separations, drug delivery, and advanced fibers. QC 20191119

Open reduction internal fixation (ORIF) metal plates provide exceptional support for unstable bone fractures; however, they often result in debilitating soft-tissue adhesions and their rigid shape cannot be easily customized by surgeons. In this work, a surgically feasible ORIF methodology, called AdhFix, is developed by combining screws with polymer/hydroxyapatite composites, which are applied and shaped in situ before being rapidly cured on demand via high-energy visible-light-induced thiol–ene coupling chemistry. The method is developed on porcine metacarpals with transverse and multifragmented fractures, resulting in strong and stable fixations with a bending rigidity of 0.28 (0.03) N m2 and a maximum load before break of 220 (15) N. Evaluations on human cadaver hands with proximal phalanx fractures show that AdhFix withstands the forces from finger flexing exercises, while short- and long-term in vivo rat femur fracture models show that AdhFix successfully supports bone healing without degradation, adverse effects, or soft-tissue adhesions. This procedure represents a radical new approach to fracture fixation, which grants surgeons unparalleled customizability and does not result in soft-tissue adhesions. QC 20210623

Effective and economical carbon dioxide-methane separation (CO2/CH4) is highly desirable in several industries such as sweetening natural gases and renewable natural gas (RNG) from biogas and landfills. Among the different separation technologies, membrane separation has been shown to have lower cost of production and lower CH4 losses. In this study, Zeolitic Imidazole Frameworks (ZIF-8) crystals with sizes varying from 45 nm to 450 nm were synthesized and incorporated in the polymer of intrinsic microporosity, PIM-1, to form mixed matrix membranes (MMMs). The structure, morphology, and physicochemical properties of the MMMs were characterized by 1H NMR, FTIR, XRD, TGA, and SEM. ZIF-8 crystal size was controlled using the concentration of sodium formate. The influence of the ZIF-8 crystal size on MMMs was studied by sorption, gas permeability, and aging of the membranes. The MMMs with ZIF-8 crystals of 120 nm particle diameter yielded the greatest improvement in gas transport properties; the CO2/CH4 selectivity-CO2 permeability was 11.4 and 9700 Barrer compared to PIM-1 with 6.4 and 9300 Barrer respectively. The former is near the Robeson 2008 upper bound, while PIM-1 is on the 1991 upper bound. After 40 days of aging, selectivity increased and permeability decreased; the changes were parallel to the Robeson upper bounds indicating increased polymer packing and diffusivity selectivity.

A quantitative analysis of degree of transformation from a softwood sulphite dissolving pulp to alkalised material and the yield of this transformation as a function of the simultaneous variation of the NaOH concentration, denoted [NaOH], reaction time and temperature was performed. Samples were analysed with Raman spectroscopy in combination with multivariate data analysis and these results were confirmed by X-ray diffraction. Gravimetry was used to measure the yield. The resulting data were related to the processing conditions in a Partial Least Square regression model, which made it possible to explore the relevance of the three studied variables on the responses. The detailed predictions for the interactive effects of the measured parameters made it possible to determine optimal conditions for both yield and degree of transformation in viscose manufacturing. The yield was positively correlated to the temperature from room temperature up to 45 A degrees C, after which the relation was negative. Temperature was found to be important for the degree of transformation and yield. The time to reach a certain degree of transformation (i.e. mercerisation) depended on both temperature and [NaOH]. At low temperatures and high [NaOH], mercerisation was instantaneous. It was concluded that the size of fibre particles (mesh range 0.25-1 mm) had no influence on degree of transformation in viscose processing conditions, apparently due to the quick reaction with the excess of NaOH. bio4Energy

In this report, the crosslinking density of bupivacaine molecularly imprinted methacrylic acid (MAA)-ethylene glycol dimethacrylate (EGDMA) copolymers was investigated through replacement of EGDMA by methyl methacrylate (MMA). The effects were examined using a series of full-scale MD simulations of pre-polymerization mixtures, equilibrium rebinding studies on the corresponding synthesized polymers and morphology characterization through nitrogen sorption measurements. While the extent of hydrogen bonding between the functional monomer MAA and bupivacaine observed in the MD pre-polymerization mixtures was comparable in each of the systems studied, the decrease in degree of crosslinking impacted directly on polymer morphology as observed in BET and BJH studies of surface area and porosity. Further, decreases in the crosslinking density induced reductions in template rebinding capacity as seen from a series of radio-ligand binding studies, demonstrating the importance of crosslinking on the performance of molecularly imprinted MAA-EGDMA copolymers, the polymer system most commonly used in molecular imprinting science and technology.

The selective ion transport characteristics of a conducting polymer electrode, based on poly(3,4-ethylenedioxythiophene) (PEDOT), is evaluated with respect to its electrocatalytic performance, specifically targeting redox switching of quinone couples. Employing model organic redox quinones, here, the novel phenomenon of ion-selective electrocatalysis (ISEC) is conceptualized. The effect of ISEC is studied and evaluated using two forms of PEDOT electrodes, which differ in their ion-exchange characteristics, by comparing the redox transformations of catechol and tiron. It is rationalized that the choice of the specific redox couple and the ion selectivity characteristics of the conducting polymer electrode impacts the activation losses in aqueous organic redox-flow batteries. By carefully selecting and designing the conducting polymer electrodes, high conversion efficiency on acid-resistant electrodes is obtained. As far as it is known, this is the first redox flow battery to include conducting polymer electrodes operating in both the posolyte and negolyte configurations, thus the first "all-organic" RFBs. Funding Agencies|Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University [2009-00971]

In the native wood cell wall, cellulose microfibrils are highly aligned and organized in the secondary cell wall. A new preparation strategy is developed to achieve individualization of cellulose microfibrils within the wood cell wall structure without introducing mechanical disintegration. The resulting mesoporous wood structure has a high specific surface area of 197 m2 g−1 when prepared by freeze‐drying using liquid nitrogen, and 249 m2 g−1 by supercritical drying. These values are 5 to 7 times higher than conventional delignified wood (36 m2 g−1) dried by supercritical drying. Such highly mesoporous structure with individualized cellulose microfibrils maintaining their natural alignment and organization can be processed into aerogels with high porosity and high compressive strength. In addition, a strong film with a tensile strength of 449.1 ± 21.8 MPa and a Young's modulus of 51.1 ± 5.2 GPa along the fiber direction is obtained simply by air drying owing to the self‐densification of cellulose microfibrils driven by the elastocapillary forces upon water evaporation. The self‐densified film also shows high optical transmittance (80%) and high optical haze (70%) with interesting biaxial light scattering behavior owing to the natural alignment of cellulose microfibrils. QC 20201221

The potential of conjugated polymers to compete with inorganic materials in the field of semiconductor is conditional on fine-tuning of the charge carriers mobility. The latter is closely related to the material morphology, and various studies have shown that the bottleneck for charge transport is the connectivity between well-ordered crystallites, with a high degree of pi-pi stacking, dispersed into a disordered matrix. However, at this time there is a lack of theoretical descriptions accounting for this link between morphology and mobility, hindering the development of systematic material designs. Here we propose a computational model to predict charge carriers mobility in conducting polymer PEDOT depending on the physicochemical properties of the system. We start by calculating the morphology using molecular dynamics simulations. Based on the calculated morphology we perform quantum mechanical calculation of the transfer integrals between states in polymer chains and calculate corresponding hopping rates using the Miller-Abrahams formalism. We then construct a transport resistive network, calculate the mobility using a mean-field approach, and analyze the calculated mobility in terms of transfer integrals distributions and percolation thresholds. Our results provide theoretical support for the recent study [Noriega et al., Nat Mater 12, 1038 (2013)] explaining why the mobility in polymers rapidly increases as the chain length is increased and then saturates for sufficiently long chains. Our study also provides the answer to the long-standing question whether the enhancement of the crystallinity is the key to designing high-mobility polymers. We demonstrate, that it is the effective pi-pi stacking, not the long-range order that is essential for the material design for the enhanced electrical performance. This generic model can compare the mobility of a polymer thin film with different solvent contents, solvent additives, dopant species or polymer characteristics, providing a general framework to design new high mobility conjugated polymer materials. Funding Agencies|Swedish Energy Agency [38332-1, 43561-1]; Knut and Alice Wallenberg Foundation through the project The Tail of the Sun; Swedish Research Council via "Research Environment grant" [2016-05990]; SeRC (Swedish e-Science Research Center)

Herein, we investigate the suitability of hen egg-white lysozyme (HEWL) as a protein matrix for dispersal of various hydrophobic dyes. Moreover, we investigate the use of a mixer mill for grinding operation as an alternative to hand grinding by mortar and pestle. HEWL and various dyes are mixed by mechanochemistry, and the resulting composite material is dissolved in aqueous acid. The samples are then exposed to conditions promoting self-assembly of HEWL into protein nanofibrils (PNFs). The effect of PNF formation on dye photophysics is investigated by spectroscopic examination by absorption and luminescence spectroscopy, and product morphology is examined by scanning electron microscopy. The self-assembly process results in protein nanofibrils functionalized with luminescent dyes. Such structures may find future applications in various devices for light emission. In addition, we demonstrate that the anticancer drug camptothecin can be incorporated into protein nanofibrils giving materials that can find application as drug delivery agents. Funding Agencies|China Scholarship Council; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University [2009-00971]

Monte Carlo and molecular dynamics simulations were performed to investigate the effect on the solubility, diffusion, and permeability of water and oxygen when adding graphene or single-walled carbon nanotubes (SWCNTs) to polyethylene (PE). When compared with pure PE, addition of graphene lowered the solubility of water, whereas at lower temperatures, the oxygen solubility increased because of the oxygen–graphene interaction. Addition of SWCNTs lowered the solubility of both water and oxygen when compared with pure PE. A detailed analysis showed that an ordered structure of PE is induced near the additive surface, which leads to a decrease in the diffusion coefficient of both penetrants in this region. The addition of graphene does not change the permeation coefficient of oxygen (in the direction parallel to the filler) and, in fact, may even increase this coefficient when compared with pure PE. In contrast, the water permeability is decreased when graphene is added to PE. The addition of SWCNTs decreases the permeability of both penetrants. Graphene can consequently be added to selectively increase the solubility and permeation of oxygen over water, at least at lower temperatures. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016, 54, 589–602