The torque curve of PVC/EVA(-14) or PVC/EVA(-14) gVC

obtained with a temperature programmable Brabender Plasticoder

gives two peaks which indicate the melting of EVA and PVC respectively

and is accompanied with three steps of morphology varying: (1) EVA fusion-PVC grain breaking

(2) EVA continuous phase-PVC agglomerate disaggregating

(3) EVA particles-PVC primary particle melting. With decreasing the feeding ratio (VC/EVA) of a graft polymerization

the melting temperature and melt viscosty of EVAgVC increase and the first torque peak approches to the second. Results shown above indicate that EVAgVC is more compatible and more mixable with PVC than EVA. It has been shown that blends with the structure of EVA networks-PVC primary particles have the highest impact resistance. EVAgVC produced under a small feeding ration is able to remain PVC EVAgVC blend a EVA network structure in a wide processing temperature range which makes the blend possessing a high impact strength.