Novel Carbon-Sulfur Bond Initiators And Investigation Of Initiating Polymerization Of Olefin

The development and exploration of novel radical initiators has always been one of the most active domain in the polymer materials science and engineering. Our laboratories have focused on developing new initiator system, and has found some esters could initiate the polymerization, for example, benzoyl ethyl lactate and 2,8- dibenzoyloxy azelaic acid diethyl ester. Introducing carboxylic acid groups into the structure of benzoyl ethyl lactate didn't depress its activity, but promoted its solubile in water. In this thesis, we will design a series of compounds with weak C-S bond, and investigate their ability of initiating polymerization.2-[(1-phenylethyl)-thio]-benzoxazole,2-[(1-phenylethyl)-thio]-benzothi-azole and 2-[(1-phenethyl)-thio]toluene-1,3,4-thiadiazole were synthesized by one-step nucleophilic substitution of 1-chloro-ethylbenzene with 2-mercapto-benzoxazole,2-mercapto-benzothiazole and 2-mercapto-5-methyl-1,3,4-thiadiazole respectively. All of them were characterized by 1H-NMR,IR and MS spectra. Initiating experiments comfirmed that these three compounds could initiate the polymerization of styrene and methyl methacrylate. Effects of polymerization time, polymerization temperature, monomer concentration, initiator concentration on polymerization were investigated. Molecular weight and molecular weight distribution of the polymer has been measured by GPC. Their characteristics were consistent with radical polymerization ones.