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The porous isotactic (it-) poly(methyl methacrylate) (PMMA) thin film, which is prepared by layer-by-layer (LbL) assembly with it-PMMA and syndiotactic (st-) poly(methacrylic acid) (PMAA) on a substrate and the successive extraction of st-PMAA, was investigated on the aspect of the mechanism of stereoregular template polymerization, inspired by the idea "molecular technology". The porous it-PMMA film was analyzed with XRD and FT-IR spectra, after the treatment with acetonitrile or a heating process, resulting in partially crystallized it-PMMA, which gave low efficiency of stereoregular template polymerization. The template polymerization under various conditions was also tested, using methacrylamide, methyl methacrylate, and acrylic acid as methacrylic acid derivatives. Furthermore, st-PMAAs with different syndiotacticity were employed to prepare the porous it-PMMA film after LbL film preparation, resulting in low yields and stereoregularity on template polymerization. The results imply that perfect polymer-polymer interaction is essential to achieve precise polymerization in stereoregular template polymerization. [ABSTRACT FROM AUTHOR]

N-Vinylamide derivatives, such as N-n-butyl-N-vinylformamides and N-isobutyl-N-vinylformamides were synthesized and copolymerized with N-vinylformamide and N-methyl-N-vinylacetamide. Lower critical solution temperature values of the copolymers were observed over a wide range of temperatures. The thermosensitive behaviors of copolymers were controlled not only by the induction rate of alkylation of N-vinylamides at the amide position but also by the chemical structures, including the hydrogen atom of the secondary amide group. [ABSTRACT FROM AUTHOR]

Copolymers of N-vinylacetamide (NVA) and its derivative (NVA-coumarin) were synthesized bearing photoresponsive moieties. The dimerization of NVA-coumarin was confirmed under irradiation with ultraviolet light (>280nm). Copolymers showed photoresponsiveness and amphiphilic characteristics, based on both poly(NVA) and coumarin. [ABSTRACT FROM AUTHOR]

A poly(trimethylene carbonate) derivative with a methoxyethoxyl group, poly[5-(2-methoxyethyoxymethyl)-5-methyl-1,3-dioxan-2-one] (poly(TMCM-MOE1OM)), was used as a block copolymer component with polylactide. The hydrophilic properties of the poly(TMCM-MOE1OM) segment resulted in nanoparticles with acetonitrile/water through a self-organized precipitation process. Wide applications of the obtained nanoparticles are expected owing to the biodegradability of both the interior and exterior parts, which are composed of different polymer backbones. [ABSTRACT FROM AUTHOR]

We designed a novel surface modification method of shaped articles from silicone-containing hydrogel using hydrosilylation reaction between silicone component and poly(ethylene glycol) (PEG) chain in order to improve the surface wettability. For the introduction of SiH group to hydrogel, in addition to copolymerization of SiH-containing methacrylate, argon gas plasma treatment was found to be effective. Hydrosilylation reaction between shaped article and PEG easily proceeded in organic solvent, and the resultant hydrogel showed reduced contact angle after the hydration in water. FTIR-ATR measurement suggested the validity of our process design concept. [ABSTRACT FROM AUTHOR]

An interpenetrating polymer network (IPN) of poly(N-vinylacetamide) (PNVA) and poly(2-hydroxylethyl methacrylate) (HEMA) was designed to deactivate agricultural chemicals. The imprinting effect of PNVA hydrogel preparation is discussed, as compared to PNVA single hydrogels and non-imprinted IPNs in the methamidophos adsorption experiments. [ABSTRACT FROM AUTHOR]