Functionalization Of Thermoplastic Elastomers And Their Properties

Fuel cell is one kind of energy converter which can directly convert chemical energy to electrical energy. The traditional internal combustion engine is limited by the Carnot cycle, so the energy convert efficiency is far lower than that of fuel cell. The membrane is one of the most important parts of the fuel cell and it can be divided into proton exchange membrane and anion exchange membrane according to the ions they deliver. There are so many merits of the AEM when compared it with the PEM. For example, the AEM possess better fuel oxidation rate and the fuel use ratio increased on the consequence of the lower fuel crossover which is because of the the hydroxyl conducted at the opposite direction of the fuel crossover.Because of the merits of the anion exchange membrane we mentioned above, it arouses scientists'interest. There are so many problems so far for the AEM such as the low conductivity and bad chemical stability. Hereby, we expect to get anion exchange membrane with better chemical stability, better thermal stability and lower prize.(1) SEBS/SIBS was grafted with chloromethylic group in the para site of the phenyl group. After that, the Poly(vinylbenzylchloride), 60/40mixture of 3- and 4-isomers are used as the primary material, the potassium permanganate are used as oxidizing agent and the microwave-assistant method was used to get carboxylic Poly(vinylbenzylchloride).We study the carboxylic reaction of two thermoplastic elastomer: polystyrene-g-polybutylene-g-polyethylene-g-polystyrene (SEBS) and we make the related measurement of the carboxylic products we get after that. We use the carboxylic SEBS reacted with o-phenylenediamine and get the benzimidazole functional SEBS.(2) The polymer materials with benzimidazole group possess better alkaline resistance than that with imidazole group and also better chemical stability. chloromethylated SEBS/SIBS was used to react with N-Methylbenzimidazole and get the N-methylbenzimidazole-group-functional membrane materials and characterized their electrochemical property, thermal property, mechanical property, chemical property.(3) Crosslinking polymer possess better mechanic property and thermal property. Because there are more chloromethyl group in PVBC, it must have bigger functional degree. N,N,N',N'-tetramethyl-1,6-hexanediamine and imidazole was used as the crosslinking agent and got the PVBC-TMHDA-SEBS,PVBC-IM-SEBS membrane and also got the PVBC-TMHDA-SIBS membrane and characterized their electrochemical property, thermal property, mechanical property, chemical property.