Effects of processing parameters andgraft-copoly(propylene/maleic anhydride) on mechanical properties of thermoplastic natural rubber composites reinforced with wood fibres

Composites have been prepared by melt blending thermoplastic natural rubber (TPNR) with wood fibre in a Plasticorder mixer at various mixing temperatures, rates of rotation, and mixing times. The TPNR was a blend of polypropylene, natural rubber, and liquid natural rubber at a PP/NR/LNR ratio of 60:30:10,which was compounded using an internal mixer.Composites containing wood fibre fractions of 0, 10, 20, and 30 wt-%, and graft-copoly(propylene/maleic anhydride) (MAPP) at concentrations from 0 to 10% were subjected to tensile tests. The compatibiliser increased the tensile strength and Young's modulus, but reduced the strain. Scanning electron microscopy of the fracture surfaces revealed that strong interfaces were formed on addition of MAPP.