A method for producing a fluoropolymer of the invention which includes polymerizing a fluoromonomer in an aqueous medium in the presence of a surfactant to provide a fluoropolymer. The surfactant includes at least one selected from the group consisting of a surfactant represented by R.sup.1a—CO—R.sup.2a—CO—R.sup.3a-A.sup.a and a surfactant represented by R.sup.1b—CO—(CR.sup.2b.sub.2).sub.n—(OR.sup.3b).sub.p—(CR.sup.4b.sub.2).sub.q-L-A.sup.b.

A method for producing a fluoropolymer of the invention which includes polymerizing a fluoromonomer in an aqueous medium in the presence of a surfactant to provide a fluoropolymer. The surfactant includes at least one selected from the group consisting of a surfactant represented by R.sup.1a—CO—R.sup.2a—CO—R.sup.3a-A.sup.a and a surfactant represented by R.sup.1b—CO—(CR.sup.2b.sub.2).sub.n—(OR.sup.3b).sub.p—(CR.sup.4b.sub.2).sub.q-L-A.sup.b.

A method for producing a fluoropolymer of the invention which includes polymerizing a fluoromonomer in an aqueous medium in the presence of a surfactant to provide a fluoropolymer. The surfactant includes at least one selected from the group consisting of a surfactant represented by R.sup.1a—CO—R.sup.2a—CO—R.sup.3a-A.sup.a and a surfactant represented by R.sup.1b—CO—(CR.sup.2b.sub.2).sub.n—(OR.sup.3b).sub.p—(CR.sup.4b.sub.2).sub.q-L-A.sup.b.

A method for producing a modified polytetrafluoroethylene, the method including: polymerizing tetrafluoroethylene in an aqueous medium in which a polymer having units based on a fluorine-free monomer is present. The fluorine-free monomer is a monomer represented by formula (1): CH.sub.2═CR.sup.1-L-R.sup.2, where R.sup.1 is a hydrogen atom or an alkyl group, L is a single bond, —CO—O—*, —O—CO—* or —O—, * is a bonding position to R.sup.2, and R.sup.2 is an alkyl group. To the total amount of tetrafluoroethylene supplied to the polymerization, a proportion of the polymer is from 0.001 to 0.050 mass %.

A method for producing a modified polytetrafluoroethylene, the method including: polymerizing tetrafluoroethylene in an aqueous medium in which a polymer having units based on a fluorine-free monomer is present. The fluorine-free monomer is a monomer represented by formula (1): CH.sub.2═CR.sup.1-L-R.sup.2, where R.sup.1 is a hydrogen atom or an alkyl group, L is a single bond, —CO—O—*, —O—CO—* or —O—, * is a bonding position to R.sup.2, and R.sup.2 is an alkyl group. To the total amount of tetrafluoroethylene supplied to the polymerization, a proportion of the polymer is from 0.001 to 0.050 mass %.

The present invention relates to a process for preparing fluoropolymers or fluoroelastomers in an aqueous medium using a non fluorinated sulfonate type hydrocarbon containing surfactant, said process comprising the steps of: (a) forming an aqueous solution comprising an non-fluorinated, hydrocarbon containing, sulfonate anionic type surfactant in a polymerization reactor; (b) pressurizing the reactor with fluoromonomers to form an aqueous emulsion; (c) initiating polymerization of said fluoromonomers; and (d) Propagating the reaction (e) Terminating the reaction after consumption of desired weight of fluoromonomers; wherein the non-fluorinated, hydrocarbon containing, sulfonate type surfactant comprises 18 to 36 carbon atoms, wherein the molecular weight of the fluoropolymer ranges from 1×10.sup.3 to 9×10.sup.8 g/mol and wherein said process is devoid of passivating the surfactant.

The present invention relates to a process for preparing fluoropolymers or fluoroelastomers in an aqueous medium using a non fluorinated sulfonate type hydrocarbon containing surfactant, said process comprising the steps of: (a) forming an aqueous solution comprising an non-fluorinated, hydrocarbon containing, sulfonate anionic type surfactant in a polymerization reactor; (b) pressurizing the reactor with fluoromonomers to form an aqueous emulsion; (c) initiating polymerization of said fluoromonomers; and (d) Propagating the reaction (e) Terminating the reaction after consumption of desired weight of fluoromonomers; wherein the non-fluorinated, hydrocarbon containing, sulfonate type surfactant comprises 18 to 36 carbon atoms, wherein the molecular weight of the fluoropolymer ranges from 1×10.sup.3 to 9×10.sup.8 g/mol and wherein said process is devoid of passivating the surfactant.

The present invention relates to a process for preparing fluoropolymers or fluoroelastomers in an aqueous medium using a non fluorinated sulfonate type hydrocarbon containing surfactant, said process comprising the steps of: (a) forming an aqueous solution comprising an non-fluorinated, hydrocarbon containing, sulfonate anionic type surfactant in a polymerization reactor; (b) pressurizing the reactor with fluoromonomers to form an aqueous emulsion; (c) initiating polymerization of said fluoromonomers; and (d) Propagating the reaction (e) Terminating the reaction after consumption of desired weight of fluoromonomers; wherein the non-fluorinated, hydrocarbon containing, sulfonate type surfactant comprises 18 to 36 carbon atoms, wherein the molecular weight of the fluoropolymer ranges from 1×10.sup.3 to 9×10.sup.8 g/mol and wherein said process is devoid of passivating the surfactant.

A fluorinated polymer suitable for deposition and capable of favorable metal patterning, is provided. A resin film containing such a fluorinated polymer as a material is provided. Further, a photoelectronic element having such a resin film in its structure is provided.

A fluorinated polymer which satisfies the following requirements (1) to (3): (1) the melting point is less than 200° C., or no melting point is observed, (2) the thermogravimetric loss rate when the temperature is increased at a temperature-increasing rate of 2° C./min under a pressure of 1×10.sup.−3 Pa, substantially reaches 100% at 400° C. or lower, (3) when the temperature is increased at a temperature-increasing rate of 2° C./min under a pressure of 1×10.sup.−3 Pa, the temperature width from a temperature at which the thermogravimetric loss rate is 10% to a temperature at which it is 90%, is within 200° C.

A fluorinated polymer suitable for deposition and capable of favorable metal patterning, is provided. A resin film containing such a fluorinated polymer as a material is provided. Further, a photoelectronic element having such a resin film in its structure is provided.

A fluorinated polymer which satisfies the following requirements (1) to (3): (1) the melting point is less than 200° C., or no melting point is observed, (2) the thermogravimetric loss rate when the temperature is increased at a temperature-increasing rate of 2° C./min under a pressure of 1×10.sup.−3 Pa, substantially reaches 100% at 400° C. or lower, (3) when the temperature is increased at a temperature-increasing rate of 2° C./min under a pressure of 1×10.sup.−3 Pa, the temperature width from a temperature at which the thermogravimetric loss rate is 10% to a temperature at which it is 90%, is within 200° C.