Synthesis Of Reactive Polymers By Suspension Polymerization And Their Applications As Compatibilizers For ABS/PET Blends

Acrylonitrile-butadiene-styrene(ABS)is a representative engineering plastic and it has been widely investigated and used in industry.However,ABS shows relatively poor mechanical properties,low heat distortion temperature and weak weather or chemical resistance,which limited its application in many areas.Meanwhile,Polyethylene terephthalate(PET)has attracted much attention in recent years because of its excellent mechanical performance:high strength,high modulus and nice chemical resistance.Despite these advantages of PET,its inherent low crystallization speed inevitably limits the application of PET as an alternative of engineering plastics.Thus the fabrication of PET/ABS blends with high performance has potentially promising utilizations in many fields.However,PET and ABS are thermodynamically immiscible and no synergistic effects can be expected by the simply blending without compatibilizers.In this work,a new type of compatibilizers with various architectures are synthesized through the suspension polymerization strategy and utilized to compatibilize the PET/ABS blends.The main contents and results are listed as follows:(1)The reactive linear polymers(RL)were synthesized by free radical copolymerization of methyl methacrylate(MMA)and glycidyl methacrylate(GMA)through suspension polymerization method.Based on the previous results,the reactive comb polymers have been synthesized by the suspension polymerization by incorporation of PMMA macromonomer in 5L reactor.The architectures of the reactive comblike polymers(RC)have been adjusted by variation of the monomer ratios,length of the macromomer,and content of the macromomer.(2)The synthesized reactive comblike polymers have been used as the compatibilizer in the ABS/PET blends.The compatibilization effects of the compatibilizers were investigated by varying compatibilizer’s molecular structures.The results showed that with the addition of compatibilizer,the size of the dispersed phase in the matrix is obviously reduced and the homogeneity of the dispersed phase increased,as compared with the pristine ABS/PET blend.Furthermore,the best compatibilization effects could be obtained for the compatibilizer with10wt%GMA,one graft per chain(M_n=2000g/mol).The morphology and properties of ABS/PET blends with different ratios was studied with the addition of RC(5wt%).The results showed that a distinct morphological transition from a“sea-island”to cocontinuous morphology was observed when the PET was 70wt%.Moreover,the ductility of the blends increases with increasing PET contents.