| 초록 |
Poly(ethylene-co-vinyl acetate)(EVA) powders containing 5wt% and 10wt% of vinyl acetate units was saponified in ethanol/KOH solution in a heterogeneous manner. Intermolecular interaction between vinyl alcohol(VOH) units in the produced poly(ethylene-co-vinyl alcohol)(EVOH) promoted the crystallization of intervening segments composed of ethylene units. Ring opening polymerization of ε-caprolactone in the presence of EVOH gave EVOH-g-PCL graft copolymers with relatively short chain branches. Even though the graft copolymerization was carried out in a homogeneous solution, all the VOH units are not equally reactive for the PCL grafting. And the unreacted VOH units decreased very slowly with the graft copolymerization time. EVOH-g-PCL decreased the domain size of the dispersed phase in low density polyethylene/biodegradable master batch blends, and thus increased their tensile properties significantly.
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