Synthesis and repellent properties of vinylidene fluoride-containing polyacrylates

Fluorinated polyacrylats with side group containing vinylidene fluoride (VDF) units (CF3(CF2)n (CH2CF2)m, n = 3, 5; m = 1, 2) were successfully synthesized. The water and oil repellency properties of these polymers are similar to those of fluorinated polyacrylate with side group containing long perfluorooctyl group (CF3(CF2)7). The thermal telomerization of CF3(CF2)5I and CF3(CF2)3I with vinylidene fluoride (VDF) provided CF3(CF2)5CH2CF2I (1b) and CF3(CF2)3CH2CF2CH2CF2I (1c), respectively. The addition of 1b with ethylene followed by hydrolysis gave CF3(CF2)5CH2CF2CH2CH2OH (2b). Treatment of 1c with ethyl vinyl ether in the presence of Na2S2O4 followed by reduction produced CF3(CF2)3CH2CF2CH2CF2CH2CH2OH (2c). Fluoroacrylates 3b–d were prepared by acrylation of the corresponding fluoroalcohols 2b–d. The semi-continuous process emulsion co-polymerization of 3a–d with octadecyl acrylate and 2-hydroxylethyl acrylate initiated by (NH4)2S2O8 in the presence of a mixture emulsifiers of polyoxyethylene(10)nonyl phenyl ether (TX-10) and sodium lauryl sulfate provided stable latexes 4a–d, respectively. The water and oil repellency properties of 4b (Rf: CF3(CF2)5CH2CF2) and 4c (Rf: CF3(CF2)3CH2CF2CH2CF2) containing vinylidene fluoride (VDF) units were similar to those of 4a (Rf: CF3(CF2)7) containing long perfluoroalkyl group and much better than those of polymer 4d (Rf: CF3(CF2)3) with short perfluoroalkyl chain. Thus, polyacrylates containing vinylidene fluoride units showed promising aspects as the alternatives to the currently used water and oil repellent agents with long perfluoroalkyl chains.