Comparison of EVA and Polyolefin Plastomer as Blend Components in Various Film Applications

Ethylene vinyl acetate (EVA) copolymers at various%VA content and AFFINITY** polyolefin plastomers (POP) were evaluated as blend components in various film applications rich in LDPE and LLDPE. The EVA resin miscibility with LDPE or LLDPE decreased as the VA content increased so that high VA EVA resins were partially or completely immiscible with LDPE or LLDPE resins. Both POP resins were miscible with LDPE or LLDPE resins. The blown films of LDPE/POP blends gave lower heat seal initiation temperature and lower haze compared to LDPE/EVA blended films. This is due to immiscibility of Elvax 3165 (18% VA) and Elvax 3128 (9% VA) with the LDPE resin. The impact and tear resistance of the POP based blown films were also superior. Oriented films of blends of POP with LLDPE and ULDPE resins exhibited significantly lower haze compared to blends of 12% VA EVA with LLDPE and ULDPE resins. Again, this is due to partial immiscibility of 12% VA EVA with LLDPE and ULDPE resins. The oriented films of blends of POP with LLDPE and ULDPE resins exhibited similar shrinkage at 90'C compared to blends of 12% VA EVA with LLDPE and ULDPE resins.