Fluorinated elastic copolymer and method for its production
View Patent ↗To provide a fluorinated elastic copolymer which is excellent in crosslinking reactivity and extrusion moldability and which is curable to obtain a rubber excellent in permanent compression set resistance, base resistance and oil resistance and particularly suitable as a covering material for electric wires. A fluorinated elastic copolymer obtained by copolymerizing tetrafluoroethylene, propylene and optionally another monomer, wherein the molar ratio (a)/(b) of repeating units (a) derived from tetrafluoroethylene to repeating units (b) derived from propylene in the fluorinated elastic copolymer is from 60/40 to 75/25, and repeating units (c) derived from said another monomer is from 0 to 10 mol % in the fluorinated elastic copolymer.
1. A fluorinated elastic copolymer obtained by copolymerizing monomers consisting of tetrafluoroethylene and propylene, wherein the molar ratio (a)/(b) of repeating units (a) derived from tetrafluoroethylene to repeating units (b) derived from propylene in the fluorinated elastic copolymer is from 65/35 to 70/30, and wherein said fluorinated elastic copolymer has a specific gravity of 1.75-1.80.
2. The fluorinated elastic copolymer according to claim 1 , which comprises iodine atoms.
3. A fluorinated elastic copolymer composition comprising the fluorinated elastic copolymer as defined in claim 1 .
4. A fluorinated elastic copolymer obtained by copolymerizing tetrafluoroethylene, propylene and a perfluoroalkyl vinyl ether, wherein the molar ratio (a)/(b) of repeating units (a) derived from tetrafluoroethylene to repeating units (b) derived from propylene in the fluorinated elastic copolymer is from 60/40 to 75/25, and repeating units (c) derived from said perfluoroalkyl vinyl ether are present in a positive amount up to and including 10 mol % in the fluorinated elastic copolymer.
5. The fluorinated elastic copolymer according to claim 4 , wherein said perfluoroalkyl vinyl ether is perfluoromethyl vinyl ether or perfluoropropyl vinyl ether.
6. The fluorinated elastic copolymer according to claim 4 , which comprises iodine atoms.
7. A fluorinated elastic copolymer composition comprising the fluorinated elastic copolymer as defined in claim 4 .