Production of eva based elastomer compatibilized and silica nanotube filled polypropylene/ thermoplastic elastomer blend nanocomposites

Polypropylene (PP) is one of the most widely used thermoplastic polymers due to its low cost, low density, easy processability and high specific properties. Polypropylene has a fragile structure at low temperatures and its low impact resistance limits its use in many engineering applications. Low impact resistance and toughness values of polypropylene are improved by blending with elastomeric polymer or by adding various fillers. In this thesis, thermoplastic elastomer poly (ethylene-co-vinyl acetate) (EVA) and organophilic surface modified halloysite nanotube (Org-HNT) were used to improve the impact resistance and toughness values of polypropylene. Maleic anhydride grafted EVA (EVA-g-MA), poly(ethylene-co-vinyl acetate-co-carbon monoxide) (EVACO) and maleic anhydride grafted PP (PP-g-MA) compatibilizers were used to improve the interactions between halloysite nanotubes and polypropylene matrix and to improve the distribution of HNTs in the matrix. PP nanocomposites were produced by a single-step (simultaneous) melt blending method. The morphological properties of the prepared nanocomposites were analyzed by Scanning Electron Microscopy (SEM). Differential Scanning Calorimetry (DSC) and Thermogravimetric Analysis (TGA) were conducted to determine the thermal properties of nanocomposites, static and dynamic mechanical analysis were performed to invetigate the mechanical properties of nanocomposites. It was found that enhanced nanotube dispersion was seen in elastomer phase, matrix phase and matrix-elastomer interface when the EVACO and EVA-g-MA compatibilizers were used in nanocomposites. This result is more pronounced when 3wt% of Org-HNTs or more were used. When the tensile test results were evaluated, the toughness value of nanocomposite having 3wt% Org-HNT and 3wt% EVACO (3H3ECO) increased by 25% compared to blend having 9wt% EVA (PP9EVA). On the other hand, the impact resistance of 3H3ECO nanocomposite increased by 29.48% compared to pure PP. 3H3ECO nanocomposite showed high damping property and average modulus value over a wide temperature range in the dynamic mechanical analyses.