Long branching in poly(vinyl acetate) and poly(vinyl alcohol). I. Crosslinking and crosslinking cleavage of poly(vinyl acetate)
1972; Inderscience Publishers; Volume: 10; Issue: 9 Linguagem: Inglês
10.1002/pol.1972.150100920
ISSN1542-9350
AutoresShun‐ichi Nozakura, Yotaro Morishima, Shunsuke Murahashi,
Tópico(s)Advanced Polymer Synthesis and Characterization
ResumoAbstract A crosslinked network was formed by the reaction of partially saponified poly(vinyl acetate) and toluylene diisocyanate in benzene. The yield of gel was markedly dependent on the degree of saponification and the concentrations of polymer and diisocyanate. Crosslinked poly(vinyl alcohol) was obtained by treating the poly(vinyl acetate) with a catalytic amount of sodium hydroxide in methanol without any change of the urethane crosslinks. The crosslink based on the urethane linkage was quantitatively cleaved by acids, especially by hydrobromic acid, releasing polymers of the same molecular weight as the original.
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