Cobalt-Mediated Radical Copolymerization of Vinylidene Fluoride and 2,3,3,3-Trifluoroprop-1-ene.

Panagiotis G Falireas,Bruno Ameduri

doi:10.3390/polym13162676

Abstract

New copolymers based on vinylidene fluoride (VDF) and 2,3,3,3-tetrafluoroprop-1-ene (1234yf) were synthesized by organometallic-mediated radical copolymerization (OMRcP) using the combination of bis(tert-butylcyclohexyl) peroxydicarbonate initiator and bis(acetylacetonato)cobalt(II), (Co(acac)2) as a controlling agent. Kinetics studies of the copolymerization of the fluoroalkenes copolymers were monitored by GPC and 19F NMR with molar masses up to 12,200 g/mol and dispersities (Đ) ranging from 1.33 to 1.47. Such an OMRcP behaves as a controlled copolymerization, evidenced by the molar mass of the resulting copolymer-monomer conversion linear relationship. The reactivity ratios, ri, of both comonomers were determined by using the Fineman-Ross and Kelen-Tüdos fitting model leading to rVDF = 0.384 ± 0.013 and r1234yf = 2.147 ± 0.129 at 60 °C, showing that a lower reactivity of VDF integrated in the copolymer to a greater extent leads to the production of gradient or pseudo-diblock copolymers. In addition, the Q (0.03) and e (0.06 and 0.94) parameters were assessed, as well as the dyad statistic distributions and mean square sequence lengths of PVDF and P1234yf.

Highlights

Fluoropolymers are outstanding specialty polymers which exhibit remarkable properties for High Tech applications [1,2,3,4]
To the best of our knowledge, vinylidene fluoride (VDF) has been successfully polymerized by cobalt-mediated radical polymerization (CMRP) [17,18], and that technique can be well-applied on the copolymerization of vinyl acetate (VAc) [19], no study has been achieved on the CMR copolymerization of VDF with 1234yf
The OMR copolymerization of VDF and 1234yf initiated by the presence of P16 using Co(acac)2 as a controlling agent was successfully conducted

Summary

Introduction

Fluoropolymers are outstanding specialty polymers which exhibit remarkable properties for High Tech applications [1,2,3,4]. Wang et al [20] reported the CMR copolymerization of chlorotrifluoroethylene (CTFE) with VAc initiated by AIBN in the presence of bis(acetylacetonato)cobalt(II), Co(acac), as a controlling agent Though both molar masses and molar compositions of the resulting copolymers could be “controlled”, Ð values of the resulting copolymers were high (~1.57). BBaasseedd oonn ssiimmiillaarr ccoonnddiittiioonnss,, tthhee ccooppoollyymmeerriizzaattiioonn ooff VVDDFF wwiitthh 11223344yyff wwaass ppeerrffoorrmmeedd,, aass iilllluussttrraatteedd bbyy SScchheemmee 11. The reactivity ratios of VDF andfV1D2F34yf were determfi1n2e34dyfby applying the FFVinDeFman−Ross [28] (FFi1g2u34ryef 5a) and Kelen−Tü9d0ös [29] (Figure 5b) ap1p0roaches It is clear tha79t regardless of the me2t1hod chosen to estimat7e9 such parameters, th2e1obtained data is rat6h2er similar in each ca3s8e (Table 3). Deteetremrmininataitoionnooffrreeaaccttiviviittyyrraattiioossffoorr tthhee CCMMRRPP ooffVVDDFFaanndd11223344yyffbbyy(a()aF) iFnienmemana-nR−oRsos sasnd caln(pobdeh)re(oKbxxey)yllKed)neipc-leTearnrüob−dxoTöynüsdadmitcöeaos(rdPbme1olo6nsd)a.betyelsO(bPMy16OR)c.MPRmcePdmiaeteddiabteydCboy(aCcaoc()a2caacn)d2 ainnidtiainteitdiabteydbbisy(tberits-(bteurtty-blcuytcyllochye-xyl)

Method

Determination of the Reactivity Ratios of VDF and 1234yf

Findings

Conclusions