Structural, thermal, mechanical and viscoelastic properties of ethylene vinyl acetate (EVA)/olefin block copolymer (OBC) blends

Abstract

In this study, ethylene vinyl acetate and olefin block copolymer (OBC) blends were prepared by meltcompounding. The effect of vinyl acetate (VA:12 and 28 wt%) and OBC (10-50 wt%) content on the morphological, thermal, and mechanical properties of EVA/OBC blends were studied in detail. Short-term flexural creep tests were also reported to investigate the time-dependent behavior of the blends. Non-isothermal crystallization results showed that, fractionated crystallization around 75C was observed in EVA (28%) blends. The creep study showed that the creep behavior of the blends significantly improves with the addition of OBC. The four-element Burgers model and the two parameter power law (Findley's) model were fitted creep curves of the blends well. The addition of OBC promoted significant gains in terms of the mechanical and solid-state viscoelastic properties.