Achieving compatibility in blends of low-density polyethylene/polyamide-6 with addition of ethylene vinyl acetate

Polymer alloys and blends, whose major advantage is the potential of achiev ing a range of physical and mechanical properties, have continued to be a s ubject of interest over recent years. Addition of a block or graft copolyme r, with chemically similar segments to those involved in the polymer blend considered, led to a variety of desirable properties. The copolymer added t o the blend functioned to promote a homogeneous dispersion of the constitue nt phases and to enhance their mutual adhesion. Such agents that enable bet ter dispersion in polymer blends are known as compatibilizers. In this stud y an attempt has been made to improve the compatibility in a polymer blend composed of two normally incompatible constituents, LDPE and PA, by additio n of a compatibilizer. The compatibilizer agent, ethylene vinyl acetate (EV A), was added to the polymer blend in ratios of 1, 5, and 10% by using a tw in-screw extruder. The effect of EVA on the crystallization of the polymer constituents was observed through DSC examinations. Furthermore, the contro l sample and all three blends of LDPE/PA(6)/EVA were subjected to examinati ons to obtain their yield and tensile strengths, elasticity modulus, percen tage elongation, izod impact strength, nardness, and melt flow index. (C) 2 001 John Wiley & Sons, Inc.