Photochemical induced polymerization of vinylidene fluoride (VDF) with hydrogen peroxide to obtain original telechelic PVDF

Abstract

The photochemical induced polymerization of vinylidene fluoride (VDF) with hydrogen peroxide, leading to original telechelic (or α,ω-difunctional) PVDF, is presented. The influence of the nature of the solvents and the [H2O2]0/[VDF]0 initial molar ratios ranging from 4 to 80% was investigated. It was shown that the lower this ratio, the higher the molecular weights of the produced telechelic polymers. 19F-NMR spectroscopy enabled the degree of polymerization. (DPn), of these fluorinated polymers or oligomers to be assessed. Interestingly, the reversed/normal ratio of VDF units in these fluorocompounds was low. The mechanism of the reaction was investigated and showed that the hydroxyl radical generated from hydrogen peroxide reacted mainly at the hydrogenated carbon atom, but also to the fluorinated site yielding CO2H end-functions. This is discussed. © 2002 Elsevier Science B.V. All rights reserved.