Industrial & Engineering Chemistry Research, Vol.58, No.47, 21864-21871, 2019
Controlled Radical Polymerization of Vinyl Chloride Mediated by Xanthene-9-Thione
The controlled radical polymerization (CRP) of vinyl chloride monomer (VCM), a low activity monomer with high radical reactivity, is still a true challenge. In this study, a novel CRP of VCM with high monomer conversion at 45 degrees C with xanthene-9-thione (XT) as mediator and bis(4-tertbutylcyclohexyl)peroxydicarbonate (TBCP) as initiator is achieved. The M-n of the produced poly(vinyl chloride) (PVC) increases slightly with increasing monomer conversion and could be mediated in the range from 6k to 12k by simply changing the molar ratio of TBCP/XT while the dispersity maintains around 2.0. The fidelity of XT dormant groups of PVC-XT is about 60-80% and depends on the ratio of TBCP/XT. With the as-prepared PVC-XT as macroinitiator, block copolymerizations of methyl methacrylate (MMA), n-butyl acrylate (BA), and styrene (St) are carried out and the PVC-bPMMA, PVC-b-PBA, and PVC-b-PSt block copolymers have been synthesized successfully.