abstract |
The invention provides a technique enabling the separation and recovery of an unreacted fluoromonomer from an aqueous fluoropolymer dispersion obtained by emulsion polymerization, without using any extraction solvent, and enabling the prevention of a hydrolysis of —SO2F and a like sulfonic acid precursor functional group convertible to sulfonic acid group. Thus, the invention provides a recovering method fluoromonomer having a sulfonic acid precursor functional group convertible to a sulfonic acid group and remaining unreacted from an aqueous fluoropolymer dispersion obtained by emulsion polymerization of the fluoromonomer, wherein the unreacted fluoromonomer is recovered from the aqueous fluoropolymer dispersion by evaporation, wherein the aqueous fluoropolymer dispersion has an acidic pH. |