Study on behaviour of melt mixing touque, rheology proporties of EVA/EVAgAM/NANOSILICA Nanocomposite

Abstract

The nanocomposites based on ethylene vinyl acetate EVA (18 % vinyl acetate group) without and with EVAgAM (EVA graft anhydride maleic) and nanosilica were prepared by melt mixing in a Haake intermixer. The melt mixing torque of the nanocomposites was recorded and reviewed by Polylab V 4.1 software. Rheological properties of the EVA/nanosilica nanocomposites were investigated using a eVOR 150 rotational rheometer vrith parallel-plate geometry' in both temperature sweep and frequency sweep modes. The obtained results showed that melt mixing torque of the nanocomposites was propotional to the complex viscosity at a certain temperature. The melt viscosity of the nanocomposites was propotional to nanosilica content and EVAgAM contributed to increase the melt viscosity of EVA/nanosilica ' nanocomposites. With the increase of nanosilica content (2-4 %), the nanocomposites exhibited stronger solid-like behaviour, the crossover point (storage modulus G’ = loss modulus G”) shifted towards the lower frequency region of G' and G”. The same result was observed for the EVA/nanosilica nanocomposites with 1 wi.°/o EVAgAM. The storage modulus (G'), which is the index of elasticity, increased with nanosilica content due to strong interaction between EVA and nanosihea, EVAgAM also increased G’ modulus of EVA/nanosilica nanocomposites. EVAgAM played as a compatibilizer for improving dispersion and adhesion between nanosilica and EVA matrix.