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Preparation of Polymer Brushes with Well-Controlled Stereoregularity and Evaluation of Their Functional Properties High-density poly(methyl methacrylate) (PMMA) brushes with well-controlled stereoregularity were prepared using a surface-initiated living anionic polymerization method in the presence of a Lewis acid. A molecular weight range from 6 K to 400 K with a narrow polydispersity index (PDI) was obtained. Grazing incidence wide-angle X-ray diffraction measurements indicated that the polymer brushes formed a helical structure approximately 1 nm in diameter and consisting of encapsulated functional molecules or polymers, leading to the formation of inclusion complexes or stereocomplexes.

Photoinduced transitions between the solid, glass, and liquid states based on molecular photoswitches promise an enormous variety of applications, such as photoswitchable adhesives, which contribute to material recycling for a sustainable future in the era of composite materials. In this review, we highlight recent progress in the photoinduced transitions of small molecules and polymers and systematically discuss the molecular designs, mechanisms, applications, merits and demerits, and future challenges in each photoswitch and the whole field.

Direct surface modification of polymer fibers and films by surface-initiated polymerizations has been investigated. The introduction of initiating sites on the polymer materials and successive polymerization produce surface-tethered polymer chains on the polymer surface. The surface-selective modification controls the surface properties such as wetting, lubrication and anti-fouling without sacrificing the bulk performances. Researches on grafting polymer chains to five types of polymers, poly(methyl methacrylate)-based copolymer, Br-containing polyolefins, poly(butylene terephthalate), poly(vinylidene fluoride-co-trifluoroethylene) and poly(ether-ether ketone) are reviewed.

Physical properties of polymer materials are deeply related to not only the primary structure but also the higher ordered structure such as periodic structures and molecular orientation. If the target material consists of ordered and non-ordered region, the former structure can be selectively detected by X-ray scattering method, whereas structural information of both the regions is obtained by infrared absorption spectroscopy. Particularly for thin film materials, infrared pMAIRS (p-polarized multiple-angle incidence resolution spectroscopy) and GI-XRD (grazing incidence X-ray diffraction methods are very useful for precise structural analyses.

The recent studies on the development of polymeric core crosslinked particles for drug delivery system are reviewed. The first part of this article describes synthesis of polymeric core crosslinked particles via the formation of nanoemulsion, characterization of the particle structure using small angle scattering techniques, and effect of polymer chain conformation on the particle pharmacokinetics and pharmacodynamics. The second part introduces zwitterionic amino acid polymer (ZAP)-based core crosslinked particles and discusses some advantages of using ZAPs as a pilot macromolecule for cancer-targeting chemotherapy.

The recent progress of research on polymer reactions utilizing dynamic covalent exchanges of alkoxyamine units—adducts of styryl and stable nitroxide radicals—is reviewed. Various types of macromolecular design, polymer reactions based on dynamic covalent exchanges of alkoxyamine units and their related research are described. Various examples of polymer reactions of main-chain-type, side-chain-type, crosslinked and star-shaped poly(alkoxyamine)s are systematically shown. The progress of the polymer reactions can be confirmed by diverse characterization techniques, such as spectroscopic, chromatographic, microscopic and scattering methods.