ETHYLENE-VINYL ALCOHOL COPOLYMER HIGH-DENSITY POLYETHYLENE BLENDS COMPATIBILIZED THROUGH FUNCTIONALIZATION

In order to evaluate the compatibilizing effects of isocyanate (NCO) f unctional groups on ethylene vinyl alcohol copolymer/high density poly ethylene (EVOH/HDPE) blends, HDPE grafted with 2-hydroxyethyl methacry late-isophorone diisocyanate (HDEP-g-HI) was prepared and blended with EVOH. The grafting was confirmed by infrared spectra, and the graftin g ratio was 4.9% from elementary analysis. From the morphologies of EV OH/HDPE-g-HI blends, it was found that an improved adhesion between th e two components and finer dispersions were produced as a result of ch emical reactions occurring during the melt blending. The depression of melting temperature of EVOH in the 10/90 EVOH/HDPE-g-HI blend indirec tly indicated increased miscibility. The tensile strength of the EVOH/ KDPE-g-HI blend was much higher than that of the EVOH/HDPE blend havin g no adhesion at each composition, and a dramatic increase in the impa ct strength was produced at the 90/10 EVOH/HDPE-g-HI blend composing o f the fine HDPE-g-HI dispersions.