Effects of EVA-g-MA and EVACO compatibilizers/tougheners on morphological and mechanical properties of PP/EVA/HNT blend polymer nanocomposites

• Published in: Journal of composite materials Vol. 54; no. 16; pp. 2195 - 2215
• Main Authors: Doğu, Salih, Tekay, Emre, Şen, Sinan
• Format: Journal Article
• Language: English
• Published: London, England SAGE Publications 01-07-2020
• Subjects: poly(ethylene-vinyl acetate-carbon monoxide) compatibilizer; halloysite nanotube; tensile properties; morphology; Polypropylene; nanocomposites
• ISSN: 0021-9983; 1530-793X
• DOI: 10.1177/0021998319893423

A series of polypropylene (PP)/poly(ethylene-co-vinyl acetate) (EVA) blend nanocomposites was produced by utilizing different amounts of organophilic halloysite nanotube (Org-HNT) and EVA-based compatibilizers/tougheners. They were prepared by using either only EVA elastomer or using EVA with the compatibilizers which are maleic anhydride grafted EVA (EVA-g-MA) and poly(ethylene-vinyl acetate-carbon monoxide) (EVACO) as well as maleic anhydride grafted PP (PP-g-MA). The morphology–mechanical property relationship was investigated as a function of nature of the compatibilizer and the amount of aluminosilicate nanotube/compatibilizer. The composites prepared without using the EVA-based compatibilizers in all nanotube loading degrees (1%, 3%, 5%) exhibited nanotube aggregates as evidenced by scanning electron microscope analyses. On the other hand, EVA-g-MA and EVACO provided a good dispersion of HNTs at both PP–EVA interface and in the PP matrix. The use of compatibilizers together with 3% Org-HNT resulted in PP/EVA blend nanocomposites with higher tensile modulus and toughness when compared to PP/EVA blend. Particularly, EVACO compatibilizer having highly polar carbonyl group at its backbone provided the highest toughness and Young’s modulus as well as impact resistance for the 3% Org-HNT loaded nanocomposite while retaining the yield strength as an indication of a good balance between stiffness/toughness.