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  • Structure of styrene and acrylate block copolymers
    Opresnik, Marko ; Koller, Jože ; Šebenik, Anton, 1941-
    Using UV light as the energy source and polystyrene- (PS-) or polymethyl methacrylate- (PMMA-) macroinitiators with active aromatic or aliphatic thiyl end groups, PS-PMMA-PEA (polyethyl acrylate) ... block copolymers were synthesized. The molecular weights of both block copolymers increased with increasing reaction time. The reactivity of macroinitiators depend on the type of thyl groups and monomer and not the length of the polymer chain. The most reactive were macroinitialtors containing resonance stabilized non-substituted or substituted aromatic end groups. The decomposition of the the macroinitiators took place over the formation of the thiyl radical and macroradical. The bond length, the bond dissociation energy, and the bond order of macroradical end groups were calculated. The most reactive monometer was ethyl acrylate; the less reactive was styrene. The structure, the molecular weight, and the ▫$T_g of the styrene-acrylate block copolymers were determined. The PMMA/PEA block copolymer had two of block's T_gs, the first at 105°C, the second at -24°C, and a third at 16°C which probably represents contacting segments.$▫
    Vir: Journal of macromolecular science. Pure and applied chemistry. - ISSN 1060-1325 (Vol. A33, no. 6, 1996, str. 759-769)
    Vrsta gradiva - članek, sestavni del
    Leto - 1996
    Jezik - angleški
    COBISS.SI-ID - 733722

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