ABSTRACT This study focuses on the preparation of hybrid polymer electrolyte films containing metal ions via a non‐aqueous sol–gel reaction of a vinyl polymer with terminal phosphonic acid moieties and metal alkoxides. Poly(poly[ethylene glycol]methyl ether methacrylate‐ co ‐4‐vinylphenylboronic acid 1,3‐propanediol ester) (poly(PEGMA‐ co ‐VPBP)) with a weight‐average molar mass of 5800 and a dispersity of 1.19 was synthesized by reversible addition‐fragmentation chain transfer polymerization using 2,2′‐azobis(isobutyronitrile) and S,S′ ‐bis(2‐ethylphosphonic acid)trithiocarbonate. MOP hybrid electrolyte films (M = metal or metalloid) containing Ti, B, Al, and Nb atoms were prepared using poly(PEGMA‐ co ‐VPBP), metal alkoxides or boron alkoxide, and lithium perchlorate. The ionic conductivities are in the order of NbOP > AlOP > BOP > TiOP at 20°C, and the NbOP hybrid electrolyte film shows an especially high ionic conductivity of 4.9 × 10 −4 mS/cm at 20°C. BOP hybrid electrolyte shows the highest conductivity of 3.0 × 10 −2 mS/cm at 40°C and the highest activation energy from the Arrhenius plots.
ABSTRACT This study investigates the mechanical performance and fracture morphology of RNM‐ and RIM135‐based epoxy composites reinforced with 1–10 wt.% Al 2 O 3 and wollastonite (CaSiO 3 ) microparticles. Specimens prepared by ultrasonic homogenization and vacuum degassing were characterized through tensile, three‐point bending, SEM, and EDS analyses. The optimum strength response was obtained for RNM composites at 2.5 wt.% filler. At this loading, Al 2 O 3 increased tensile and flexural strengths by 5.6% and 23.0%, respectively, while CaSiO 3 increased flexural strength by 16.1%. The maximum tensile modulus increases were 22.9% for RNM/CaSiO 3 and 40.4% for RIM135/CaSiO 3 . The highest flexural modulus improvements reached 94.0% for RNM/Al 2 O 3 and 68.4% for RIM135/CaSiO 3 , the latter occurring at 7.5 wt.%. However, high filler contents considerably reduced strength, deformation capacity, and energy absorption. In RIM135/Al 2 O 3 composites, tensile strength and tensile energy absorption decreased by up to 60.2% and 89.2%, respectively, while flexural strength and energy absorption decreased by up to 52.8% and 75.6%. SEM observations revealed uniform dispersion at low loadings but increased agglomeration, particle pull‐out, and interfacial debonding at higher contents. Overall, low‐to‐moderate filler loadings provided the best balance between stiffness and mechanical integrity.
ABSTRACT Poly(vinyl alcohol)/chitosan (PVA/CS) composite membranes containing kraft lignin (KL) were prepared by solvent casting followed by thermal cross‐linking with sulfosuccinic acid (SSA) in a hot press. The effect of incorporating varying amounts of KL filler on the composite structure, properties, and cross‐linking behavior was thoroughly studied. Interactions between KL and the PVA/CS matrix limit the incorporation of SSA due to a reduced availability of functional groups, particularly at higher KL contents. Consequently, the ion exchange capacity and water uptake decrease, ultimately reducing the proton conductivity and diffusion of the membranes. Higher KL loadings promote stronger covalent cross‐linking, resulting in denser surface morphologies, reduced dimensional swelling, and restricted polymer chain mobility. In addition, disruption of the hydrogen‐bonding network is observed at high lignin contents due to the increased cross‐linking density and possible lignin aggregation, leading to brittle membranes with reduced stability. In contrast, composites with low lignin content favor the formation of strong hydrogen bonds, thereby enhancing oxidative stability, onset thermal degradation, and tensile strength. Controlled lignin incorporation prior to thermal cross‐linking allows balancing the intermolecular interactions within the composite and tailoring the membrane properties for use in energy‐related applications.
ABSTRACT The versatility and fundamental importance of macromolecular materials make them key contributors to progress and innovation in science, medicine, and technology. This review provides an overview of developments in polymer materials inspired by biological systems and designed for selective interactions, drawing on the work of Denizli and colleagues. It surveys a variety of both synthetic and natural macromolecular materials, such as cryogels, macroparticles, microparticles, and bacterial cellulose, and discusses their unique properties and potential uses. The article highlights progress in designing polymers with biomimetic and affinity‐based characteristics, with particular attention to molecularly imprinted polymers (MIPs) in different physical forms. Recent innovations in the structural design and functional capabilities of these materials are explored, reflecting their growing importance across scientific research and practical applications in technology and industry.
ABSTRACT Poly(lactic‐co‐glycolic acid) (PLGA) is a promising biodegradable polymer for melt electrowriting (MEW), yet how composition governs processing stability and degradation remains unclear. Here, ordered microfibrous scaffolds were fabricated by MEW using PLGA with lactic acid‐to‐glycolic acid (LA‐to‐GA) ratios of 80:20, 70:30, and 50:50. Processing stability was evaluated via continuous printing, followed by 6‐month in vitro hydrolytic degradation. Morphology, thermal transitions, molecular weight, weight loss, and mechanics were characterized. All compositions showed progressive jet‐speed increases and gradual mechanical deterioration during prolonged MEW, indicating thermally induced changes in melt processability. During degradation, higher GA content accelerated molecular‐weight reduction, weight loss, and structural collapse. After 8 weeks, PLGA (80:20), PLGA (70:30), and PLGA (50:50) exhibited approximately 36%, 68%, and 90% weight loss, respectively. Molecular weight declined substantially before measurable weight loss in all formulations, consistent with bulk degradation. Hydrolysis‐induced molecular rearrangement and crystallization occurred in PLGA (80:20) and PLGA (70:30), whereas amorphous PLGA (50:50) underwent rapid structural failure without comparable thermal transitions. These results demonstrate that the LA‐to‐GA ratio governs degradation kinetics, long‐term processing stability, and mechanical durability of MEW‐fabricated PLGA scaffolds. This work provides guidelines for designing biodegradable scaffolds with tunable degradation for tissue engineering and biomedical applications.
