13C MAS n.m.r. study of solid poly(vinyl alcohol) and of ethylene-vinyl alcohol copolymers
نویسندگان
چکیده
منابع مشابه
study of ethylene/vinyl acetate transformation to ethylene/vinyl alcohol copolymer by nmr and dsc
hydrolysis of ethylene-vinyl acetate copolymer in alkaline conditions using two systems of naoh/methanol and koh/isopropanol has been studied and the formation of ethylene-vinyl alcohol copolymer was systematically examined using nmr spectroscopy and dsc measurements. vinyl acetate weight percentage and the degree of hydrolysis were calculated from nmr spectroscopy and it is shown that hydrolys...
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Rotational isomeric state theory has been used to calculate mean-square unperturbed dimensions (r2>0 and dipole moments (/~> of ethylene-vinyl chloride copolymers as a function of chemical composition, chemical sequence distribution, and stereochemical composition of the vinyl chloride sequences. As was previously found for several other copolymeric chains, (/z2> is much more sensitive to chemi...
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ژورنال
عنوان ژورنال: Polymer
سال: 1990
ISSN: 0032-3861
DOI: 10.1016/0032-3861(90)90144-n