Novel Polymer Syntheses by Anionic Polymerization of Fluoroalkyl Alpha-Fluoroacrylates

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The anionic polymerization reactivity of fluoroalkyl alpha-fluoroacylates such as methyl alpha-fluoroacrylate (CH_2=CFCOOCH_3)(MFA) and 2, 2, 2-trifluoroethyl alpha-fluoroacrylate (CH_2=CFCOOCH_2CF_3) (TFEFA) was investigated. In the radical polymerization some detailed studies were carried out on MFA and ethyl alpha-fluoroacrylate (EFA), and Q, e-values were reported to be : 0.47 and 0.73 for MFA, and 0.49 and 0.68 for EFA, respectively. It was probable these high e-values suggested that alpha-fluorbacrylates should show high anionic polymerization reactivity. Although n-C_4H_9Li and C_2H_5MgBr produced poly (MFA) in very low yields, ate complexes such as LiZnC_4H_9(C_2H_5)_2 and LiAIC_4H_9(C_2H_5)_3 produced poly (MFA) with appreciable yields. Organoaluminum compoun ds showed generally higher activity compared to organozinc initiators. (C_2H_5)_2Al(NCCHCOOC_2H_5)(Et_2AlECA) and Et_2Al(CH_3OCOCHCOOCH_3) showed the highest polymerization reactivity.In order to get some information on the polymerization mechanism, initiation reaction of MFA with Et_2AlECA was carried out. According to the results the initiation reaction was found to be rather slow since about 35% of Et_2AIECA was consumed in 4 hours. The initiation reaction of the polymerization of MFA with Et_2AlECA was inferred to take place in anionic fashion. The simple addition polymerization of the vinyl group took place predominantly without any remarkable side reactions in the systems of MFA and TFEFA polymerizations since the molecular weight distributions were unimodal and no peaks assignable to vinyl protons or other additional signals were observed in ^1H NMR.The results of ^<13>C- and ^<19>F-NMR measurements of poly (MFA) suggested the possibility that the microstructure of fluorinated polymers could be analyzed by ^<19>F-NMR spectra though the analyses of the microstructures of the polymer have mainly been carried out by ^<13>C-NMR spectra.