Study On The Grafting Of Polyolefin With MAH And GMA By Reactive Extrusion

The compatibility between polyolefin and other materials can be improved via grafting-modified polyolefin to introduce polar or functional lateral group. The application realm of polyolefin can be extended in this way. On the basis of present research results on the reactive extrusion of polyolefin both at home and abroad, The author chose three typical reaction extruding systems, which are linear low density polyethylene (LLDPE)/dicumyl peroxide (DCP)/maleic anhydride (MAH), polypropylene (PP)/dicumyl peroxide (DCP)/maleic anhydride (MAH) and polypropylene (PP)/dicumyl peroxide (DCP)/glycidyl methacrylate (GMA), as the research targets to study reaction extruding grafts in the twin screw extruder. The effects of initiator and monomer concentrations, rotating velocity, temperature, styrene (St) co-monomer and addition agent N, N-dimethylformamide (DMF) were investigated and the graft products which had better graft degree and MFR were gained. The graft structure and graft degree were determined and tested by IR spectra and DSC. On the basis of these studies, the effect of PP graft product on mechanical properties of PP/PA6 blend was investigated and the interior structure of the blend was analyzed by SEM.On the study of LLDPE-g-MAH, The IR spectra showed MAH was successfully grafted onto PP backbone, and the relational curve between absorbance ratio and graft degree was gained. The graft degree rose and then dropped and MFR decreased all the while with the increase in DCP content. The graft degree increased remarkably and then decreased, but MFR decreased and then increased with the increase in MAH content. In a definite temperature range the graft degree rose with the increase in temperature. The graft degree rose and then dropped with the increase in screw speed.