The article about the alternating copolymerization of carbonyl sulfide with phenyl glycidyl ether was published on Polymer Chemistry by Ming Luo
Abstract: Polymer structures containing sulfur atoms can provide enhancement of important polymer properties compared to their oxygen-containing counterparts. In this regard, the copolymerization of phenyl glycidyl ether and carbonyl sulfide has been very effectively achieved employing (salen)CrCl in the presence of an onium salt at ambient temperature. The resulting copolymer is shown to be completely alternating and to possess extremely high regioselectivity in the epoxide ring-opening step. That is, the ring-opening step predominantly occurs at the less sterically hindered methylene carbon–oxygen bond leading to a tail-tohead structure (98%) in the copolymer. This observation was further confirmed when using the chiral epoxide monomer, (S)-PGE.