THERMOSTABILITY OF POLYSTYRENE BY STYRYLQUINOLINE CONTAINING METHACRYLATES

Abstract

It's known that polystyrene is one of the most widely used plastics. The materials based on it are used in almost all branches of engineering and human's daily life. Therefore, the creation of new highly effective thermal stabilizers for polystyrene remains as the actual task of polymer chemistry. Combining fragments of basic industrial monomer with the modifiers in the polymer matrix provides the ability to control performance properties of obtained materials. Investigation of thermostabilitive action of new styrylquinoline containing methacrylic monomers on polystyrene have been described in this work. Polystyrene and copolymers based on styrene and new methacrylic styrylquinoline containing monomers were synthesized by free radical thermoinitiated polymerization. 2,2´-Azo-bisisobutyronitrile (1 mass per cent) was used as initiator. Styrylquinoline monomers (3 mol per cent) were added to styrene for making modified samples. Polymerization was carried out by heating of reactants in ethyl acetate during 16 hours. Polymers were precipitated in isopropanol and dried at vacuum. The impact of such dopants – 2-[2-(4-methoxyphenyl)ethenyl]quinolin-8-yl 2-methylpropyl-2-enoate (М1), 2-(2-phenylethenyl)quinolin-8-yl 2-methylpropyl-2-enoate (М2), 2-[2-(4-nitrophenyl)ethenyl]quinolin-8-yl 2-methylpropyl-2-enoate (М3) were investigated. Thermostability of polystyrene and modified samples styrene:M1, styrene:M2, styrene:M3 were studied by dynamic thermograviametric analysis. It was shown that destruction of polystyrene with dopants M1-M2 starts at 41–42°С higher than reference polystyrene prepared at the same conditions and polystyrene of brand STYRONE (Switzerland). Sample with dopant M3 begins destruction with lower speed than reference polystyrene. First one loses 20% of weight at 347°С while reference polystyrene loses 50% of weight. It means, that dopant M3 can act as retarder of thermal destruction of polystyrene. It was found that new monomers have thermal stabilizing effect after its covalent introducing and can act as effective inhibitors of thermodestruction of polystyrene in the air.