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Postpolymerization modifications of poly(2-methoxyethoxycarbonylmethylene) and poly(2-phenoxyethoxycarbonylmethylene) with mixtures of Me₃SiCl and LDA efficiently transformed the alkoxycarbonylmethylene repeating units to ketene silyl acetals to yield a product with up to 93 mol% composition of the latter unit. TBAF-mediated benzylation of the highly silylated polymer with benzyl bromide yielded a polymer containing side chain O (major)- and main chain C (minor)-benzylated units along with the unreacted ketene silyl acetal unit.

Pd-initiated polymerization of diazoacetates containing oligo(ethylene glycol)-substituted cyclotriphosphazenes was conducted to yield carbon-carbon main chain polymers bearing an oligo(ethylene glycol)-substituted cyclotriphosphazene on every main chain carbon atom. The resulting organic–inorganic poly(substituted methylene)s were found to show an LCST-type phase separation in aqueous media, and thus their thermosensitive behavior was evaluated by turbidity measurements.

Conformation of poly(γ-benzyl-L-glutamate) (PBLG) in the block copolymers in which polystyrene (PS) was attached to the N terminus (PBLG_n-N-PS_m) or the C terminus (PS_n-C-PBLG_m) of PBLG was studied in trifluoroacetic acid (TFA)–chloroform mixture at various concentrations. Contribution of the PS segment to helix–coil transformation of PBLG was obvious in PS_n-C-PBLG_m rather than in PBLG_n-N-PS_m, indicating that conformational free energy of the C terminus in the PBLG chain differs from that of the N terminus.

Radical copolymerization of alkyl 2-norbornene-2-carboxylates 1a–c with alkyl (meth)acrylates to afford copolymers bearing norbornane framework in the main chain is described. γ-Butyrolactone- and hydroxy group-containing norbornene-based monomers 1b and 1c were newly synthesized and their radical copolymerization behavior with n-butyl acrylate was examined. Methyl 2-norbornene-2-carboxylate 1a and the new monomers 1b and 1c were employed as a comonomer for radical terpolymerization with lactone- and adamantane-containing (meth)acrylates to afford copolymers, which could be utilized as new chemically amplified 193-nm photoresist materials.