Co-cured blends of fluoroelastomers of tetrafluoroethylene-propylene copolymer with cure site monomer and terpolymers of Vinylidene fluoride (VDF), Hexafluoropropylene (HFP) and Tetrafluoroethylene (TFE) with peroxide as initiator and coagent TAIC as crosslinker show improved curing performance, improved mechanical properties and improved compression set as well. The co-cured fluoroelastomers show improved chemical resistance to the solvent aging systems and better retention of mechanical properties after aging at high temperature in the solvents system.

Described herein is a composition comprising (i) a hydrofluorothermoplastic polymer, wherein the hydrofluorothermoplastic polymer is derived from: (a) 50-85 mol % tetrafluoroethene; (b) 2-15 mol % hexafluoropropene; (c) 10-35 mol % vinylidene fluoride; and (d) 0.1 to 5 mol % of a bromine-containing monomer; and (ii) a perhalogenated thermoplastic polymer. Such compositions can be used in multilayer constructions in, for example, fuel hose applications.

Provided herein are copolymers that comprise copolymerized residues of a perfluorotrivinyltriazine monomer of Formula 1.

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Preferred R.sub.f groups include, without limitation, (CF.sub.2).sub.n (n=1-6); (CF.sub.2).sub.m[OCF(CF.sub.3)CF.sub.2].sub.p (m=1-4, p=1-4); and [(CF(CF.sub.3)O).sub.x(CF.sub.2).sub.k] (x=1-3, k=1-5). Preferred comonomers for copolymerization with the perfluorotrivinyltriazine monomer (1) include, without limitation, tetrafluoroethylene (TFE); vinylidene fluoride (VF2); hexafluoropropylene (HFP); vinyl fluoride (VF); EVE; PSEPVE; perfluoro-(long chain vinyl ethers); E; P; PFBE; PEVE; EVE-OH; EVE-P; PDD; and the cure-site monomers BTFB, ITFB, 8-CNVE, 8-SAVE, and the like. Also provided are methods of synthesizing the copolymers and articles comprising the copolymers.

Co-cured blends of fluoroelastomers of tetrafluoroethylene-propylene copolymer with cure site monomer and a pentapolymer of vinylidene fluoride (VDF), hexafluoropropylene (HFP), tetrafluoroethylene (TFE), perfluorinated methyl vinyl ether (PMVE) and ethylene (PE) with peroxide as initiator and coagent TAIC as crosslinker show improved curing performance, improved mechanical properties and improved compression set as well. The co-cured fluoroelastomers show improved chemical resistance to the solvent aging systems and better retention of mechanical properties after aging at high temperature in the solvents system.

Described herein is a composition comprising a fluorothermoplastic polymer, wherein the fluorothermoplastic polymer is derived from: (a) 60-85 mol % tetrafluoroethene; (b) 2-12 mol % hexafluoropropene; (c) 10-30 mol % vinylidene fluoride; (d) 0.2 to 5 mol % of a bromine-containing monomer. Such compositions can be used in multilayer constructions in, for example, fuel hose applications.

Described herein is a latex blend comprising (i) an amorphous perfluoropolymer and (ii) an aqueous dispersion of semi crystalline fluoropolymer particles, wherein the particles comprise a TFE homopolymer or a TFE copolymer comprising no more than 1 wt % of a second fluorinated monomer, wherein the semi crystalline fluoropolymer particles (a) have an MFI (372? C. with 2.16 kg) of less than 50 g/10 min or (b) are not melt processible and have an SSG of less than 2.190, wherein the semi crystalline fluoropolymer particles have an average diameter greater than 100 nm.

The invention provides novel pellets having high fluidity in a hopper of an extruder and capable of forming a coating layer having good wire diameter stability and capacitance stability even when used for rapid molding of electric wire coating. The pellets contain a fluororesin. Each of the pellets, placed on a horizontal surface, has a substantially circular outline or a substantially elliptic outline and has a major axis D.sub.1 of 3.1 mm or shorter and a minor axis D.sub.2 of 3.1 mm or shorter when observed in the direction normal to the horizontal surface. Each pellet satisfies the following formula (1): (D.sub.1+D.sub.2)/2L=1.8 to 2.6, wherein D.sub.1 represents the major axis, D.sub.2 represents the minor axis, and L represents the height from the horizontal surface to the highest point of the pellet.

Described herein is a millable fluorinated block copolymer having at least one A block and at least one B block, wherein the A block is a semi-crystalline segment comprising repeating divalent monomeric units derived from TFE, HFP and VDF; and the B block is a segment comprising repeating dilvalent monomeric units derived from HFP and VDF; and wherein the millable fluorinated block copolymer has a modulus of 0.1 to 2.5 MPa at 100 C.

The invention relates to a heterogeneous, co-continuous copolymer composition of vinylidene fluoride and at least one other comonomer. Preferred comonomers are hexafluoropropylene and perfluoroalkylvinyl ether. The co-continuous morphology is provide by first forming a first phase polymer, then adding one or more comonomers before half of the original monomer stream has been added, and at an effective level to cause phase separation of the copolymer. The co-continuous morphology provides a means for incorporating a high level of comonomer into the copolymer with little or no adverse effect on the melting temperature. The morphology also provides the copolymer composition with a unique combination of properties, including a high melting point, good flexibility and good low temperature impact resistance. The unique properties of the polymer make it useful in end-use application where those properties provide performance advantages, such as in the wire and cable market, and in oil and gas applications.

The invention relates to a heterogeneous, co-continuous copolymer composition of vinylidene fluoride and at least one other comonomer. Preferred comonomers are hexafluoropropylene and perfluoroalkylvinyl ether. The co-continuous morphology is provide by first forming a first phase polymer, then adding one or more comonomers before half of the original monomer stream has been added, and at an effective level to cause phase separation of the copolymer. The co-continuous morphology provides a means for incorporating a high level of comonomer into the copolymer with little or no adverse effect on the melting temperature. The morphology also provides the copolymer composition with a unique combination of properties, including a high melting point, good flexibility and good low temperature impact resistance. The unique properties of the polymer make it useful in end-use application where those properties provide performance advantages, such as in the wire and cable market, and in oil and gas applications.