Synthesis And Applications Of Functional Copolymer Containing Of MAH, AMS And St

Polyolefin is a kind of commercial polymer product that has a huge production in industry. Blending them with other polymers can overcome their own disadvantages and expand their range of applications and industrial value. The increase of compatibility of polyolefin with other polar polymers (such as PA6) is the key to modify polyolefin blend. Generally, compatibility of the blend system could be improved by the addition of functional polyolefin, which served as an effective compatilizer. Grafting polymerization of polylefin with fuctional monomers in melting state is usually used to the functionalization of polyolefin. However, organic peroxide initiators are commonly used in grafting polymerization process, which have some inherent limitations, such as aging polymer, decreasing mechanical properties of the polymer, toxic gas and environment-unfriendly processing and so on. To solve this problem, we proposed a strategy to synthesis a new functional random copolymer containing maleic anhydride, styrene and a-methyl styrene (R-PASM), which can be decomposed at high temperature due to presence ofa-methyl styrene(AMS). Owing to their unique thermal decomposing propertyAnd the properties this random copolymer have which is depolymerizing when heat is based on the properties of the a-methyl styrene(AMS).1. The synthesis of R-PASM throuh a semi-continuous injection method. The solution of maleic anhydride in butanone was added continuously into the butanone solution containing AMS, St and the initiator(BPO). By this way we got R-PASM random copolymer. IR and NMR spectra of the product showed that the product was indeed ter-polymer, and the content of MAH in R-PASM was determined by acid-base titration(21-39%). DSC curves and 13C-NMR spectra could prove that R-PASM is indeed a random copolymer. The result of TGA revealed that the degradation of the product will occur when being heated.2. Grafting of polypropylene(PP) with R-PASM in melt phase. Infrared spectra proved that the grafting reaction was happened between PP and R-PASM, but the grafting efficiency was very low(GP is 0.07-0.42%), indicating that the grafting reaction was not inefficient. The result of the contact angle measurements and SEM images could explain the reason why the efficiency of the grafting reaction was so low.3. Compatibilization of PS/PA6 blends with R-PASM. The influence of R-PASM content on the compatibilization of PS/PA6 blends was investigated in detail. The SEM results showed that the diameter of the dispersed phase (PS), reduced from 100um to 10um when R-PASM was added as a compatibilizer in PS/PA6 blends. The DSC results demonstrated the crystallinity and the crystallization temperature of PA6 decreased after the addition of R-PASM, which was surely a sign of improving compatibilization. The results of mechanical properties test of the PS/PA6 blends showed that the tensile strength and impact strength of blends increased to some exent, demonstrating that R-PASM made great contribution to enhance the miscibility between PS and PA6 component in PP/PA6 blends.