Study On Double-monomer Melt Grafting PP Compatibilizes PVC/PP Blends

A graft polymer [PP-g-(GMA-co-St)]was made by using melt grafting way in a single-screw extruder. The effects elements on GR , MFR and the mechanical properties were investigated, that is, the category of grafting monomerGMA or MAH and it's content, the category of comonomer of St orα-MSt and it's content, the content of DCP, the molar ratio of GMA to St, the reactive temperature and speed of extruder , and so on. The GR ,the heat stability, crystallization/melting of PP-g-(GMA-co-St)were tested by means of FTIR, DSC and TG respectively. The results showed that GMA was used as grafting monomer is better than MAH, the additon of St can enhance GR obviously and suppress the degradation of the PP matrix in the process of grafting. The mechanical properties,heat-resistence ability of PP-g-(GMA-co-St)are better than PP-g-GMA,but it's MFR was lower. The best grafting conditions is PP/GMA/St/DCP=100/6/3/0.3, T=170℃~190℃,the speed of extrude is 20r/min. The Tm was decreased with the increase of GR. the higher GR of PP-g-(GMA-co- St),the lower of Tc,but XCDwas higher.PVC/PP/PP-g-(GMA-co-St)blends were made in double-screw extruder.The compatibility of PP-g-(GMA-co-St)to PVC/PP blends was tesed by using Molau, tests and FTIR. The adding means , GR and the content of PP-g-(GMA-co-St)was invested by testing mechanic properties(TSb, LSIzod and HL), resistance to thermal distortion and MFR. The heat stability was tested by using TG. The morphology were investigated by means of SEM and TEM. The results showed that blends had the better properties when PP,PVC and PP-g-(GMA-co-St)were added into double-screw extruder in one step. The properties of blends increased with adding PP-g-(GMA-co-St)and got to maximum value when contenting it 20%~30%. The compatibility and interfacial interaction between PVC and PP was increased by thining dispersion phase,improving dispersive equlity of PP phase. Under outer forces, the destruction of PVC/PP/ PP-g-(GMA-co-St)blend was the PP matrix becoming deformed instead of the the PP and PVC phase pulled out from the matrix.