Study Of Radical Solution Polymerization Of Vinylidene Fluoride Initiated By Organic Peroxide

Mechanism of radical homopolymerization and copolymerization of vinylidene fluoride was presented by solution polymerization initiated by organic initiator. The initiator was prepared by ourself, and the full name is diperfluoro(2-n-propoxy propionyl peroxide). After analyzing the type of the initiator decomposition radical and its relationship with the binding mode of the vinylidene fluoride monomer, the copolymerization of vinylidene fluoride was made. Preparation of copolymer of vinylidene fluoride with1-bromo-2,2-difluoroethylene (BDFE) and Perfluoro(4-methyl-3,6-dioxaoct-7-cnc)sulfonyl fluoride (PSVE) were initiated by perfluoropcroxide mentioned above.The microstructure, thermal stability, end groups of homopolymers and copolymers obtained were characterized by19F and1H NMR spectroscopy, melting temperature(Tm) and glass transition temperature(7g) measured by differential scanning calorimetcr(DSC) and decomposition tempcrature(TDEC) measured by thermogravimetric apparatus(TGA). From the assignments of the NMR signals, the presence of end groups of CF3CF2CF2OCF(CF3)～was mainly found in both VDF homopolymers and copolymers initiated by perfluoroperoxide, which was generated from the decomposition of the initiator. This end groups enabled the assessment of the molecular weight of VDF homopolymers and copolymers.Using different monomer molar ratios to make several experiments. According to the Fineman-Ross method, the reactivity ratios for both comonomers were rVDF=1.21a nd rBDFE=0.463at35℃, rVDF=0.59and rPSVE=0.050at35℃. And according to the Fo x equation, the glass transition temperature(Tg) of homopolymers were TgBDFE=-17.7℃, TgPSVE=-25.4℃.