Journal of Polymer Science Part A: Polymer Chemistry, Vol.38, No.8, 1344-1354, 2000
Radical copolymerization of novel trifluorovinyl ethers with ethyl vinyl ether and vinyl acetate: Estimating reactivity ratios and understanding reactivity behavior of the propagating radical
Two novel trifluorovinyl ether (TFVE) monomers were copolymerized with either ethyl vinyl ether (EVE) or vinyl acetate (VAc) in a redox-initiated aqueous emulsion: 1-(2-phenoxyethoxy)-1,2,2-trifluoroethene (Ph-TFVE) and 1-[2-(2-ethoxyethoxy)ethoxy]-1,2,2-trifluoroethene (Et-TFVE). Previous studies demonstrated a propensity for radical hydrogen abstraction from the oligoether pendant group during the homopolymerization of Et-TFVE with continued propagation of the resulting radical, thereby providing the rationale to investigate the copolymerization of our new TFVEs with EVE or VAc. Reactivity ratios were estimated using the error-in-variables model from a series of bulk free radical copolymerizations of Ph-TFVE with EVE or VAc. The reactivity ratios were r(Ph-TFVE) = 0.25 +/- 0.07, r(EVE) = 0.016 +/-0.04; r(Ph-TFVE) = 0.034 +/- 0.04, r(VAc) = 0.89 +/- 0.08. Partial hydrolysis of polymers containing VAc to vinyl alcohol (VA) resulted in two terpolymers: poly(Ph-TFVE-co-VAc-co-VA) and poly(Et-TFVE-co-VAc-co-VA), respectively. We investigated the possibility of hydrogen abstraction from VAc during polymerization by comparing the molar mass before and after hydrolysis. Abstraction from VAc was not apparent during polymerization; however, abstraction from the oligoether pendant group of Et-TFVE was again evident and was more significant for those copolymers having a greater fraction of Et-TFVE in the monomer feed.