Synthesis and properties of poly(trifluoroethylene) via a persistent radical mediated polymerization of trifluoroethylene. Issue 7 (31st January 2018)

• Record Type: Journal Article
• Authors: Colpaert, Maxime; Banerjee, Sanjib; Ladmiral, Vincent; Ono, Taizo; Améduri, Bruno
• Is Part Of: Polymer chemistry. Volume 9:Issue 7(2018)
• Page Start: 894
• Page End: 903
• Publication Date: 2018-01-31
• Subjects: Polymers -- Periodicals; Macromolecules -- Periodicals; Polymerization -- Periodicals; 547.705
• DOI: 10.1039/c7py02018j
• Languages: English
• ISSNs: 1759-9954

Abstract

Abstract : Poly(trifluoroethylene) exhibiting excellent thermal stability was synthesized by the radical polymerization of trifluoroethylene initiated by an innovative persistent radical. Abstract : The conventional radical homopolymerization of TrFE initiated by a ˙CF3 radical (generated in situ from perfluoro-3-ethyl-2, 4-dimethyl-3-pentyl persistent radical, PPFR) is presented. Reactions were carried out at an increasing PPFR concentration (initial [TrFE]0 : [PPFR]0 molar ratios varying from 2.5 to 20.0 mol%) to influence the molar masses ( M n, ranging between 7700 and 38 100 g mol −1 ). PTrFE homopolymer yields were high (76–87%). The microstructures of such synthesized PTrFEs were characterized by 1 H and 19 F NMR spectroscopy. The generated PTrFE chains were exclusively terminated by CF3 end-groups, as revealed by MALDI-TOF spectroscopy and NMR analysis, indicating that the ˙CF3 radicals initiated the polymerization of TrFE. The addition of the ˙CF3 radicals onto TrFE was predominantly regioselective (66%) leading mainly to a CF3 –CHF–CF2 –PTrFE homopolymer. Furthermore, the CF3 end group could be used as an efficient label to determine the PTrFE molar masses by 19 F NMR spectroscopy that also enabled us to assess the chain defects (14%). The thermal properties of these CF3 –PTrFE–CF3 polymers revealed (i) a high thermal stability (their degradation under an oxidative atmosphere started from 362 °C and ranged even up to 428 °C for higher molar masses of PTrFEs) and (ii) a semi-crystalline behavior with a crystallinity rate averaging 36%.