Abstract:
Perfluoroelastomer compositions comprising perfluoroelastomers having copolymerized units of tetrafluoroethylene, a perfluoro(vinyl ether), and a nitrile-containing cure site monomer are cured with certain nitrogen-containing nucleophilic compounds. The nucleophilic compounds also act as dual curatives in perfluoroelastomer compositions which incorporate other curing agents.
Abstract:
Perfluoroelastomers that contain high levels (i.e. about 40 mole percent or more) of perfluoro(alkyl vinyl ether) copolymerized units can form stable blends with higher levels of perfluoropolyethers than can perfluoroelastomers that contain lower levels of perfluoro(alkyl vinyl ether) units. Thus, the former blends have better low temperature properties than the latter.
Abstract:
In a process for the manufacture of perfluoroelastomers, a weak organic acid, e.g. glacial acetic acid, is employed to coagulate an acidic perfluoroelastomer dispersion.
Abstract:
Curable perfluoroelastomer compounds are prepared by mixing a composition comprising perfluoroelastomer, 1-20 phr fibrillating PTFE, and curative for a time ML (ASTM D5289), measured on sequential samples of compound taken at 5 minute intervals, differ by less than 5%. Articles are made therefrom by curing the compounds to form crosslinks.