Melt grafting of maleic anhydride onto low-density polyethylene/polypropylene blends

Grafting of maleic anhydride (MAH) onto low-density polyethylene/polypropylene (LDPE/PP) blends was performed by melt extruding in the presence of dicumyl peroxide (DCP). The melt viscosities of the grafted blends were measured by a capillary rheometer and the grafting degrees were determined by a back-titration procedure. Compared to the MAH grafted LDPE, the MAH grafted LDPE/PP (90/10) blend had lower viscosity when the DCP or MAR concentration increased in the grafting procedure. However, the grafting degree of the MAH grafted LDPE/PP (90/10) blend was almost the same as or a little higher than that of the MAH grafted LDPE. The characteristic groups of MAH in the grafted products were measured by Fourier transform infrared spectroscopy (FT-IR). The results showed that MAH had grafted onto both LDPE and PP in the blend. (C) 2002 Elsevier Science Ltd. All rights reserved.