The Influence of Dimethyl Hydrogen Siloxane on Polypropylene-Straw Fibres Interface

This paper describes the characteristics of polypropylene-straw fibres composite interfaces. Surface chemical modification of straw fibres was carried out by poly(methylhydrogen siloxane) (PMHS) to enhance compatibilization. Dried straw fibres weregrafted with PMHS and then melt blended with polypropylene. All treatments even at lowdegrees of grafting significantly changed the hydrophilic nature of the straw fibres surfacesto hydrophobic one and improved the wetability of the straw fibres by the matrix whichlead to improved adhesion. The rheological and morphological properties of compositewere studied and results show that at low loadings, the viscosity of the treated straw fibres composite is reduced because of low molecular weight of PHMS. Water absorption of treated and untreated straw fibres was studied and results indicated the enhanced improvement in hydrophobic nature of treated fibres. Untreated and treated straw fibres with different amount of coating were floated on water for 2 h, results show that the water absorption is minimum in straws treated with 2 wt% of each PMHS and catalyst.