Résumé
After an introduction reporting the properties and the applications of fluoropolymers, the advantages and uses of polyvinylidene fluoride (PVDF) are presented. According to the nature and the amount of the comonomer, the copolymers of VDF can be thermoplastic1,2, elastomeric 2 or thermoplastic elastomers 3. Usually, they exhibit a random structure. This presentation, illustrated by numerous examples, shows a browse of copolymers of VDF with non-halogenated, fluorinated 4, commercially available or synthesized 4-6 comonomers. The interest of these last ones lies on their structure and on their functionality that enable these comonomers to be more or less easily incorporated in the copolymer. Consequently, they introduce reactive side groups that greatly improve the crosslinking of the obtained copolymers. This is the case of monomers exhibiting a F2C=CFX(CF2)x(CH2)y- structure where X , x, y and stand for O, «-» ; 0, 1, 2 ; 1-10 and a function such as OH, OAc, SAc, CO2R 6, SF5 5, Si(OR)3 7, respectively. In addition, recent investigation on the unexpected alternating radical copolymerization of VDF with -trifluoromethacrylic acid was achieved, in emulsion, even without any surfactant 6. The kinetics of copolymerization 3 of (VDF, M) couples where M designates a commercial or synthesized comonomer led to the assessment of the reactivity ratios. A reactivity series of these M comonomers about a macroradical terminated by VDF is proposed. In addition, new VDF-containing copolymers that exhibit well-controlled architectures (alternating, block or graft copolymers) are reported 3. Finally, original examples of VDF-telechelic compounds, precursor of well-defined structured polycondensates are presented, the fluorinated segments bringing softness and thermal stability. Several properties and applications of these VDF copolymers will illustrate this presentation. 1- C. Tournut, Modern Fluoropolymers, Chapter 31, pp. 557-571, Wiley (1997). 2- B. Ameduri, B. Boutevin, Well Architectured Fluoropolymers: F-Telomers, Telechelics, and Alternating, Graft, and Block Copolymers, Elsevier, Amsterdam, 2004. 3- B. Ameduri, B. Boutevin, J. Fluorine Chem. 126 (2005) 221-230. 4- a) B. Ameduri, G. Bauduin, B. Boutevin, G. Kostov, P. Petrova, Macromolecules, 32 (1999) 4544-4552; b) J. Guiot, B. Ameduri, B. Boutevin, J. Polym. Sci., Part A, Polym. Chem. 40 (2002) 3634-3643. 5- G. Kostov, B. Ameduri, W.R. Dolbier, G. Gard, Macromolecules, 38 (2005) 8316-8326. 6- Ameduri, B.; Boyer, C. Japanese Patent Application 2007/51201 2006 (Assigned to Tosoh F-Tech, Japan). 7- T. Lannuzel, J. Guiot, B. Ameduri, B. Boutevin, USP 0160972, 2006 (assigned to Solvay).