Polyolefins (PE, PP, EPDM, EPR, EVA, etc.) have poor compatibility with other materials, such as polar polymers and inorganic fillers, because of their nonpolarity and crystallinity. By adding the compatibilizer prepared in advance or formed in situ, the original incompatible polymer can form a blend with unique properties that none of the components has. As a kind of surfactant, compatibilizer can reduce the surface tension and improve the interfacial adhesion between dispersed phase and continuous phase.In order to expand the application of polyolefin and develop more valuable new materials, functional polyolefin as compatibilizer has been an important field in scientific research and industrial production. So far, Maleic Anhydride Grafted Compatibilizer is the most important functional polyolefin because of its low cost, high activity and good processability. It is widely used in polymer blends, polymer / inorganic fillers, polymer / organic fibers, composite reinforcement materials and binders.
There are many methods of grafting maleic anhydride onto polyolefin, such as solution method, melting method, radiation method and solid phase method. But the most important method is melting, which is called “reactive extrusion”. The mechanism of melt grafting is very complex, and there are serious side reactions, such as the crosslinking of polyethylene grafting, the degradation of polypropylene, and the simultaneous occurrence of two side reactions in ethylene propylene rubber. Add some electron donor compounds containing N, P, S atoms, such as dimethylformamide (DMF)
Dimethylacetamide (DMAC) can inhibit these side reactions such as crosslinking and degradation.Melt grafting can be carried out in single screw extruder, twin screw extruder or Brabender rheometer. The polyolefin, MAH monomer, initiator and other additives are dispersed in a small amount
