Fracture behavior and morphology of LLDPE/NR blends prepared by reactive blending with maleic anhydride

Abstract

Fracture behavior of blends containing linear low density polyethylene (LLDPE) and natural rubber (NR) was studied via mechanical properties. The blends were prepared by reactive blending using maleic anhydride (MA) as a reactive compatibilizer and dicumyl peroxide (DCP) as an initiator. Mechanical properties such as high-speed impact strength, tear strength, tensile strength, and creep were investigated as a function of MA, DCP, and NR concentrations. For 90/10 LLDPE/NR, increasing MA increases impact strength and tear strength, while increasing DCP increases impact strength, but decreased tear strength. For the 50/50 blend, increasing M A and DCP enhances impact strength, but shows little effect on tear strength. Based on tensile creep tests, the addition of DCP enhances the resistance to deformation. After exposure to accelerated weathering, the blends exhibit decreasing tensile strength and elongation at break. With increasing NR content, a lower percent reduction in tensile strength and higher percent reduction in tensile elongation at break were found for blend with high N R content. Tear strength decreases with increasing NR content. Impact strength shows a weak dependence on NR content.