A copolymer including fluorinated units of formula (I):

—CX.sub.1X.sub.2—CX.sub.3X.sub.4—  (I)

in which each of the X.sub.1, X.sub.2, X.sub.3 and X.sub.4 is independently chosen from H, F and alkyl groups including from 1 to 3 carbon atoms which are optionally partially or totally fluorinated; and fluorinated units of formula (II):

—CX.sub.5X.sub.6—CX.sub.7Z—  (II)

in which each of the X.sub.5, X.sub.6 and X.sub.7 is independently chosen from H, F and alkyl groups including from 1 to 3 carbon atoms which are optionally partially or totally fluorinated, and in which Z is a photoactive group of formula —Y—Ar—R, Y representing an oxygen atom or an NH group or a sulfur atom, Ar representing an aryl group, and R being a monodentate or bidentate group including from 1 to 30 carbon atoms. Also, a process for preparing this copolymer, a composition including this copolymer, and a film obtained from this copolymer.

A copolymer including fluorinated units of formula (I):

—CX.sub.1X.sub.2—CX.sub.3X.sub.4—  (I)

in which each of the X.sub.1, X.sub.2, X.sub.3 and X.sub.4 is independently chosen from H, F and alkyl groups including from 1 to 3 carbon atoms which are optionally partially or totally fluorinated; and fluorinated units of formula (II):

—CX.sub.5X.sub.6—CX.sub.7Z—  (II)

in which each of the X.sub.5, X.sub.6 and X.sub.7 is independently chosen from H, F and alkyl groups including from 1 to 3 carbon atoms which are optionally partially or totally fluorinated, and in which Z is a photoactive group of formula —Y—Ar—R, Y representing an oxygen atom or an NH group or a sulfur atom, Ar representing an aryl group, and R being a monodentate or bidentate group including from 1 to 30 carbon atoms. Also, a process for preparing this copolymer, a composition including this copolymer, and a film obtained from this copolymer.

Provided is a polyvinylidene fluoride comprising: vinylidene fluoride unit; and a pentenoic acid unit represented by formula (1): CH.sub.2═CH— (CH).sub.2—COOY wherein Y represents at least one selected from the group consisting of an inorganic cation and an organic cation, a content of vinylidene fluoride unit is 95.0 to 99.99 mol % based on all monomer units of the polyvinylidene fluoride, and a content of the pentenoic acid unit is 0.01 to 5.0 mol % based on all monomer units of the polyvinylidene fluoride.

The present invention relates to a vehicle tyre comprising a piezoelectric device, wherein the piezoelectric device comprises a layer of a piezoelectric polymer having first and second opposing sides, and a first and a second layer of conductive rubber provided adjacent to the first and second opposing sides of the layer of piezoelectric polymer.

Provided is a composition including a polyvinylidene fluoride (A); and a vinylidene fluoride polymer (B) excluding the polyvinylidene fluoride (A), wherein the polyvinylidene fluoride (A) comprises vinylidene fluoride unit and a pentenoic acid unit represented by formula (1): CH.sub.2═CH—(CH).sub.2—COOY wherein Y represents at least one selected from the group consisting of an inorganic cation and an organic cation, a content of vinylidene fluoride unit of the polyvinylidene fluoride (A) is 95.0 to 99.99 mol % based on all monomer units of the polyvinylidene fluoride (A), and a content of the pentenoic acid unit of the polyvinylidene fluoride (A) is 0.01 to 5.0 mol % based on all monomer units of the polyvinylidene fluoride (A).

Provided is a composition including a polyvinylidene fluoride (A); and a vinylidene fluoride polymer (B) excluding the polyvinylidene fluoride (A), wherein the polyvinylidene fluoride (A) comprises vinylidene fluoride unit and a pentenoic acid unit represented by formula (1): CH.sub.2═CH—(CH).sub.2—COOY wherein Y represents at least one selected from the group consisting of an inorganic cation and an organic cation, a content of vinylidene fluoride unit of the polyvinylidene fluoride (A) is 95.0 to 99.99 mol % based on all monomer units of the polyvinylidene fluoride (A), and a content of the pentenoic acid unit of the polyvinylidene fluoride (A) is 0.01 to 5.0 mol % based on all monomer units of the polyvinylidene fluoride (A).

The invention pertains to a process for the manufacture of a fluoropolymer film, to the fluoropolymer film obtainable therefrom and to use of said fluoropolymer film in electrochemical and photo-electrochemical devices.

A polymer for an electrode protective layer including a polymer (A) including a fluorine-based polymer in which a monomer unit including poly(alkylene oxide) and a monomer unit including a curable functional group (e.g., a thermocurable functional group or a photocurable functional group) are grafted on the fluorine-based polymer, and when preparing an electrode by coating an electrode active material layer using the polymer and curing (e.g., thermally curing or photocuring) the result, excellent lithium ion conductivity is obtained since lithium ion flow is not inhibited, chemical resistance for an electrolyte liquid is high, and voltage stability of a secondary battery may be enhanced by suppressing side reactions with the electrolyte liquid occurring on an electrode active material surface due to properties of a uniform and flexible protective layer.

A polymer for an electrode protective layer including a polymer (A) including a fluorine-based polymer in which a monomer unit including poly(alkylene oxide) and a monomer unit including a curable functional group (e.g., a thermocurable functional group or a photocurable functional group) are grafted on the fluorine-based polymer, and when preparing an electrode by coating an electrode active material layer using the polymer and curing (e.g., thermally curing or photocuring) the result, excellent lithium ion conductivity is obtained since lithium ion flow is not inhibited, chemical resistance for an electrolyte liquid is high, and voltage stability of a secondary battery may be enhanced by suppressing side reactions with the electrolyte liquid occurring on an electrode active material surface due to properties of a uniform and flexible protective layer.

A polymer for an electrode protective layer including a polymer (A) including a fluorine-based polymer in which a monomer unit including poly(alkylene oxide) and a monomer unit including a curable functional group (e.g., a thermocurable functional group or a photocurable functional group) are grafted on the fluorine-based polymer, and when preparing an electrode by coating an electrode active material layer using the polymer and curing (e.g., thermally curing or photocuring) the result, excellent lithium ion conductivity is obtained since lithium ion flow is not inhibited, chemical resistance for an electrolyte liquid is high, and voltage stability of a secondary battery may be enhanced by suppressing side reactions with the electrolyte liquid occurring on an electrode active material surface due to properties of a uniform and flexible protective layer.