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BUTLER, GEORGE B.,DO, CHOON H.,ZERNER, MICHAEL C. 순천대학교 기초과학연구소 1990 基礎科學硏究誌 Vol.1 No.-
The stereochemistry of alternating copolymers of styrene (ST) with maleic anhydride (MA) was examined by ^13C-NMR spectroscopy, and the stabilization energies and the most stable geometries of complexes and adducts between ST and MA were calculated by the PVCILO program and by INDO/1. The methine and carbonyl atoms of the MA portion and the quaternary carbon atom of the ST portion reveal defferent stereochemistries due to various polymerization conditions, suggesting that the donor-acceptor complex may participate in the copolymerization. The complex postulated according to the Diels-Alder geometry was more stable than that according to [2+2] cycloaddition geometry. It is believed that the stabilization energy is so great that the copolymerization occurs spontaneously via forming a donor-acceptor complex and adducts. The geometries of 1:1 adducts formed by endo and exo approaches in the Diels-Alder geometry mode were also calculated.
Coon, H. Do,George B. Butler 순천대학교 기초과학연구소 1990 基礎科學硏究誌 Vol.1 No.-
Since the discovery that radical polymerization of dialkyl-diallylammonium saits yields water-soluble cyclopolymers instead of cross-linked polymers, 1-5 homo- and co-cyclopolymers of various diallylamine compounds have been extensively studied and their syntheses, kinetics, ring-sizes, properties, and applications have been reviewed. 6-11 cyclopolymerization of the diallylammonium compounds produces mostly ring structures and the content of double bonds is less than 0.1-3% in the case of poly(diallyldimethylammonium chloride, DADMAC). Free diallylamines do not polymerize but by their protonated and quaternary ammonium salts polymerize by radical initiation. Although the piperidinium ring is thermodynamically favorable, the kinetically favorable pyrolidinium ring exists dominantly in the cyclopolymer of DADMAC according to C NMR spectroscopic studies. The size of the ring also depends on the size of N-substituted alkyl groups.