Synthesis of sulfur-rich polymers: copolymerization of episulfide with carbon disulfide by using [PPN]Cl/(salph)Cr(III)Cl system.

The completely alternating copolymerization of propylene sulfide with carbon disulfide was first achieved. Copolymerization by using anionic initiator [Ph3PNPPh3]Cl gave poly(propylene trithiocarbonate). The addition of chromium complex was found to accelerate the copolymerization. The obtained copolymer has a completely alternating structure with high regioregularity and showed large refractive index of 1.781∼1.782.