Anti-Sticking Perfluoroelastomer Articles and Methods of Making
Assignee3M Innovative Properties Company
InventorsYuta Suzuki, Tatsuo Fukushi
Life of this patent
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Abstract
Methods of making anti-sticking perfluorinated articles are described. The methods include molding curing, and heat-treating a composition prepared from a coagulated and dried blend of latex dispersions of a perfluoro-elastomeric gum and a perfluoroplastic. The curing steps are performed at temperatures below the melting point of the perfluoroplastic, while the heat-treatment step occurs at a temperature above this melting point. The resulting articles are also described.
Claims18
A method of making a fluoroelastomer article comprising
- (i) molding a composition into a shape, the composition comprising a coagulated and dried latex blend comprising
- (a) a perfluoro-elastomeric gum comprising, based on the total moles of repeat units in the gum, 0.5 to 4 mole % of repeat units of a curesite monomer, 46 to 80 mole % of tetrafluoroethylene repeat units, and 16 to 50 mole % of perfluoro ether repeat units selected from the group consisting of perfluorovinyl ethers, perfluoroallyl ethers, and combinations thereof, provided that the total amount of tetrafluoroethylene and perfluoro ether repeat units is at least 96 mole % of the total moles of repeat units in the perfluoro-elastomeric gum;
- and
- (b) a perfluoroplastic having a melting point of at least 290° C., the perfluoroplastic comprising, based on the total moles of repeat units in the perfluoroplastic, at least 85 mole % tetrafluoroethylene repeat units, and 1.5 to 12 mole % of perfluoro ether repeat units selected from the group consisting of perfluorovinyl ethers, perfluoroallyl ethers, and combinations thereof;
- (ii) curing the composition using one or more curing steps to form a cured structure comprising the cured perfluoroelastomer, wherein each curing step occurs at a curing temperature below the melting point of the perfluoroplastic;
- and
- (iii) heat-treating the cured structure at a heat-treating temperature of at least 5° C. above the melting point of the perfluoroplastic for a heat-treating time of at least 5 minutes to form the fluoroelastomer article.
A cured fluoroelastomer article having a core surrounded by surface, the article comprising
- (a) a cured perfluoro-elastomeric gum comprising, based on the total moles of repeat units in the gum, 0.5 to 4 mole % of repeat units of a curesite monomer, 46 to 80 mole % of tetrafluoroethylene repeat units, and 16 to 50 mole % of perfluoro ether repeat units selected from the group consisting of perfluorovinyl ethers, perfluoroallyl ethers, and combinations thereof, provided that the total amount of tetrafluoroethylene and perfluoro ether repeat units is at least 96 mole % of the total moles of repeat units in the perfluoro-elastomeric gum;
- and
- (b) a perfluoroplastic having a melting point of at least 290° C., the perfluoroplastic comprising, based on the total moles of repeat units in the perfluoroplastic, at least 85 mole % tetrafluoroethylene repeat units, and 1.5 to 12 mole % of perfluoro ether repeat units selected from the group consisting of perfluorovinyl ethers, perfluoroallyl ethers, and combinations thereof;
- wherein the cured perfluoro-elastomeric gum and the perfluoroplastic are present through out the core of the article, the perfluoroplastic is present at the surface of the article, and the surface comprises dimples having an average diameter of 5 to 50 microns.
Dependencies are inferred from the claim text.