In the study of ring-opening polymerization of α-vinyl cyclic 1,3-disulfone, 2-methyl-2-(2-propenyl)-1, 3-dithiane-1, 1, 3, 3-tetraoxide (MPDTA-2 ) was prepared and its polymerization behavior was investigated.
Polymerization of MPDTA-2 was carried out with radical and photo initiators under various condition. MPDTA-2 polymerized in high conversion with AIBN and BPO. However, with DTBP and BME as photo initiator the polymerization failed to give any polymeric product.
The chemical structures of these polymers were determined by NMR and IR spectra. From the analysis of these spectra, it was confirmed that polymerization proceeded in mixed mode of 1, 2-type (vinyl mode) and 1, 8-type (rign-opening mode). The extent of ring opening was about 75 % as estimated from integration values of the $^1H$-NMR spectra and was not strongly affected by kinds of initiators and concentration of monomers. It is thought that the participation of 1, 8-type may be from the stability of initially formed tertiary radical. This polymer decomposed around 300℃ as determined by TGA and exhibited a glass transition at 90℃.
