One-step reactive extrusion of PP/AS alloys was studied by using a twin-screw extruder at the presence of dicumyl peroxide (DCP). Compared with mechanical extrusion

reactive extrusion greatly reduced the dispersed particle size. It is due to the formation of graft copolymer

which behaves as in situ formed compatibilizer in the blends. In order to suppress the degradation of PP chains during the process

some coagents containing double-bond were added in combination with DCP. It was recognized that the coagent which has proper molecular weight and suitable double-bond content could lead to suppression of PP degradation

and promote the grafting reaction simoltaneously. It was found that the multifunctional monomer glycerol trilinoleate (GTL) is a suitble coagent in this case. By adding DCP and GTL at the proper contents

the morphology and mechanical properties of PP/AS alloys were greatly improved.