Mechanical and degradability properties of polyethylene/ PBL composites in a wet-dry controlled environment

Several blends of polyethylene (PE) and powdered breadfruit leaf (PBL) were prepared in an internal mixer at a temperature above the glass transition of PE without additives. Formulations were based on PE/PBL ratio of 100/0, 90/10, 85/15, 80/20 and 75/25 on a dry weight basis. The effects of PBL content on the composite mechanical properties was evaluated in terms of tensile, flexural and hardness Rockwell test. The results showed increase of elastic and flexural modulus of the composites with increasing PBL contents. The tensile strength, yield strength, yield strain and hardness decreased with increasing PBL contents in the composites. The flexural strength slightly decreased with the presence of the PBL but independent on the percentage of the PBL particles. Degradability of the composites was investigated using wet–dry cycle test. It was found that the composite with higher content of PBL showed higher degradation rate. The morphological change was observed by scanning electron microscope (SEM). The results show morphological change of the composites was started from the surface composites mainly on the biodegradable PBL.