Production method for polyvinylidene fluoride aqueous dispersion liquid, and polyvinylidene fluoride aqueous dispersion liquid
The present invention aims to provide a production method that can produce an aqueous dispersion containing polyvinylidene fluoride with high productivity. The present invention relates to a method of producing an aqueous dispersion of polyvinylidene fluoride, including: emulsion polymerization of vinylidene fluoride in the presence of a surfactant, an organic peroxide, and water to produce an aqueous dispersion that contains polyvinylidene fluoride. The surfactant has a surface tension of 55 mN/m or smaller when added in an amount of 1000 ppm.
1. A method of producing an aqueous dispersion of polyvinylidene fluoride, the method comprising:
emulsion polymerization of vinylidene fluoride in the presence of a surfactant, an organic peroxide, and water to produce an aqueous dispersion that contains polyvinylidene fluoride,
the surfactant having a surface tension of 21 mN/m or more and 55 mN/m or smaller when added to water in an amount of 1000 ppm,
wherein the organic peroxide is at least one selected from the group consisting of di-t-butylperoxide, di-n-propyl peroxydicarbonate, di-t-hexylperoxide, 2,5-dimethyl-2,5-di(t-butylperoxy)hexane, 2,5-dimethyl-2,5-di(t-butylperoxy)hexyne-3, and t-butyl peroxyisobutyrate,
wherein the surfactant is at least one selected from the group consisting of
the surfactants represented by Formula (1):
wherein R 1 and R 2 independently represent a C1 to C14 alkyl or halogenated alkyl group; at least one of R 1 and R 2 is a C1 to C14 halogenated alkyl group; the alkyl or halogenated alkyl group may contain an oxygen atom between carbon atoms if the alkyl or halogenated alkyl group contains 2 to 14 carbons; R 3 represents H or —(CH 2 ) v —COOM 1 ; R 4 represents —SO 3 M 2 or —(CH 2 ) v —COOM 1 ; v represents an integer of 0 to 3; M 1 and M 2 independently represent H, NR 4 or an alkali metal; and four Rs independently represent H or a C1 to C3 alkyl group,
the surfactants represented by Formula (2):
wherein R 5 and R 6 independently represent a C1 to C14 alkyl or halogenated alkyl group; the alkyl or halogenated alkyl group may contain an oxygen atom between carbon atoms if the alkyl or halogenated alkyl group contains 2 to 14 carbons; two M 1 s independently represent H, NR 4 or an alkali metal; and four Rs independently represent H or a C1 to C3 alkyl group, and
the surfactants represented by Formula (3):
wherein R 7 and R 8 independently represent a C1 to C14 alkyl or halogenated alkyl group; the alkyl or halogenated alkyl group may contain an oxygen atom between carbon atoms if the alkyl or halogenated alkyl group contains 2 to 14 carbons; R 9 represents —SO 3 M 2 or —COOM 1 ; M 1 and M 2 independently represent H, NR 4 , or an alkali metal; four Rs independently represent H or a C1 to C3 alkyl group; and w represents an integer of 0 to 3.
2. The method according to claim 1 ,
wherein vinylidene fluoride alone is emulsion polymerized.
3. The method according to claim 1 ,
wherein the organic peroxide is at least one selected from the group consisting of di-t-butylperoxide, di-t-hexylperoxide, 2,5-dimethyl-2,5-di(t-butylperoxy)hexane, 2,5-dimethyl-2,5-di(t-butylperoxy)hexyne-3, and t-butyl peroxyisobutyrate.