Morphology and Properties of Polyolefin Elastomer /Poly(lactic Acid) /Polyamide 6 In Situ Special‐Shaped Microfibrillar Composites: Effect of Composition Ratio

Abstract In situ microfibrillar composites, which with poly(lactic acid)/polyamide 6 (PLA/PA6) together formed special‐shaped structure microfibrils in ethylene–octene copolymer(POE) matrix, were successfully fabricated by using multistage extrusion technology. The morphology of dispersed phase was greatly influenced by the content of PLA/PA6. With the content of PLA/PA6 increasing from 5% to 30%, the morphology of dispersed phase turned from short rod‐like special‐shaped microfibrils into “gourd‐skewers‐like” structure microfibrils and the number of microfibrils increased. When the content of PLA/PA6 was 25%, the “gourd skewers” structure of microfibrils was most obvious. Owing to the large specific surface area and the “hang nail” effect of “gourd skewers” structure microfibrils, the excellent tensile strength of 20.1 MPa and elongation at break of 876% were achieved in the POE/(PLA/PA6) composites when the content of PLA/PA6 was 25%, which were 2 and 1.9 times higher than those of pure POE, respectively. In addition, when the PLA/PA6 content less than 10%, there were low temperature crystallization peak of PA6 in the cooling curves. When the PLA/PA6 content reached at 20%, the cold crystallization peak and recrystallization peak of PLA appeared in the heating curves. When the PLA/PA6 content was 30%, the rheological properties of composites were best.