Super impact absorbing bio-alloys from inedible plants

Abstract

Injection molded bio-alloys based on polyamide 11 (PA11), 100% bio-based plastics from inedible plants, and polypropylene (PP) mixed with the maleic anhydride-modified ethylene-butene rubber copolymer (m-EBR) were prepared using a twin-screw extruder. The mechanical properties and morphologies of the bio-alloys were investigated using flexural tests, Charpy notched impact tests, field emission-scanning electron microscopy (FE-SEM), Raman spectroscopy, and transmission electron microscopy (TEM). The bio-alloy had a flexural modulus of 1090 ± 20 MPa and a Charpy notched impact strength of 98 ± 5 kJ m⁻², which is superior to that of polycarbonates. The FE-SEM observations revealed that the bio-alloy has a unique “salami-like structure in a co-continuous phase”, and the TEM observations showed that some m-EBR formed 10 to 20 nm wide continuous interphases between the PP and PA11 matrices. Continuous rubber interphases played an important role in enhancing the impact strength. The bio-alloys exhibited good rigidity and excellent impact strength, making them feasible for applications in automobiles and other industries.