Polymer Journal

Bio-based polyamide nanocomposites were synthesized from itaconic acid, hexamethylenediamine, and layered silicates (MMT and SA). Structurally, MMT is a dioctahedral smectite with octahedral substitutions, whereas SA is a trioctahedral smectite with tetrahedral substitutions. To prevent thermal degradation and ensure uniform clay nanolayer dispersion via fine pulverization, the composites were prepared using melt-blending followed by liquid nitrogen cryogenic treatment.

In recent years, expectations for plant-derived materials have increased due to concerns about environmental problems caused by plastics. We made the Japanese washi paper transparent by soaking it in solutions of cellulose derivatives, which are plant-derived materials, and then drying. The washi made transparent with methylcellulose shows superior light transmittance, tensile strength, and shape retention compared to others paper. By achieving both light transmittance and strength through transparency, it enables applications such as blinds and lighting.

A novel biobased, photo-hydrolyzable poly(lactic acid) (PLA) copolyesters with pyrrolidone group were synthesized by using itaconic acid. These itaconic acid-modified PLAs allow the backbone to degrade rapidly in simulated seawater. Under UV light, a photoinduced reaction opens the rings and breaks down the backbone. This approach establishes an accelerated degradation pathway without compromising the thermomechanical properties.

Organic–inorganic hybrid nanomaterials based on supramolecularly assembled nanogels combine the biocompatibility of polysaccharides with the unique physicochemical properties of inorganic nanoparticles. This Focus Review highlights three representative biomedical applications: magnetically guided intracellular protein delivery using iron oxide nanoparticles, near-infrared light-activated photodynamic therapy using upconversion nanoparticles, and boron neutron capture therapy using boron-containing nanogels and boronic oxide nanoparticles. These modular hybrid nanosystems demonstrate the potential of supramolecular engineering to advance next-generation nanomedicine.

Contrast-changed small-angle neutron scattering (SANS) was applied to directly investigate the adsorption behavior of styrene–butadiene rubber (SBR) and carboxymethyl cellulose (CMC) on graphite in lithium-ion battery slurries. While SBR showed negligible adsorption, CMC formed an adsorption layer on graphite, increasing the apparent surface fractal dimension. These results demonstrate that contrast-changed SANS provides a powerful approach for selectively detecting polymer adsorption in multicomponent slurries and offers structural insight into slurry design.

Proton transfer anionic polymerization (PTAP), a controlled anionic polymerization proceeding via reversible C–H activation, was extended to 2-vinylpyridine (2VP) to expand its monomer scope. Through systematic optimization of chain-transfer agents, ligands, and alcohol additives, precise molecular weight control was achieved at 0 °C without organometallic reagents. Sequential PTAP further enabled the synthesis of well-defined poly(N,N-diethylacrylamide)-b-poly(2VP) block copolymers.

This study investigates the changes in crosslinked structures of vulcanized butadiene rubber (BR) under uniaxial elongation using atomic force microscopy (AFM) nanomechanics. AFM results demonstrated that entanglements are dissolved by elongation, leading to a decrease in elastic modulus, and similar phenomena were confirmed by TD-NMR measurements.

Tunable enzymatic degradability was achieved in poly(ε-caprolactone)-based segmented polyurethanes and poly(urethane-amide)s through segmental composition regulation. By varying soft-segment length and hard-segment chemistry, the degradation behavior of these segmented polymeric materials could be systematically tuned due to changes in microphase separation behavior and crystallinity. The established segmental composition-degradability relationship provides fundamental insights for developing biodegradable polymers with programmable degradation lifetimes for potential biomedical and sustainable material applications.

We report the homopolymerization of dithiane-substituted allylic monomers, in which the 1,2-dithiane group and α-olefin are connected through a tosyl amide linker. Reactive secondary carbon radicals initiate radical ring-opening of disulfide bonds to incorporate tosylthiomorpholine units. The formed thiyl radicals propagate by adding to olefins or 1,2-dithiane rings. This affords polymers with two randomly distributed repeat units bearing main-chain disulfide linkages.