Synthesis and Properties of (Alkylthio)methyl-Substituted Poly(oxyalkylene)s and (Alkylsulfonyl)methyl-Substituted Poly(oxyalkylene)s

Abstract

(Alkylsulfonyl)methyl-substituted poly(oxyalkylene)s were synthesized in two steps. (Alkylthio)methyl-substituted poly(oxyalkylene)s were made by the reaction of poly[oxy(chloromethyl)ethylene] (CE), poly[oxy(chloromethyl)ethylene-co-oxyethylene] (CEE), or poly[oxy-2,2-bis(chloromethyl)trimethylene] (BCT) with sodium alkanethiolates. Then they were oxidized to (alkylsulfonyl)methyl-substituted poly(oxyalkylene)s using m-chloroperbenzoic acid. Their structures were confirmed by NMR and IR. The polymer glass transition temperatures (Tg's) decreased as the number of carbon atoms in the alkyl side chains increased, except for the Tg of (n-pentylsulfonyl)methyl-substituted CE (the number of carbon atoms in the side chain is 5). Its Tg was about that of (butylsulfonyl)methyl-substituted CE. TGA studies showed that side-chain length did not affect the thermal decomposition behavior. However, polymers with different backbones had slightly different thermal decomposition behaviors. The solubility of the (alkylsulfonyl)methyl-substituted poly(oxyalkylene)s strongly depended on the side-chain length. (Methylsulfonyl)methyl-substituted poly(oxyalkylene)s were soluble only in polar solvents, such as DMAc, DMSO, and formic acid. (Alkylsulfonyl)methyl-substituted poly(oxyalkylene)s with long alkyl side chains were also soluble in less polar solvents, such as CHCl3 and THF.