Patent ID: 8664323

Claim:
A fluorinated composition comprising: (a) from 51 to 95 parts by weight of a first polyfluoropolyether silane represented by the formula: R fa O(CF(CF 3 )CF 2 O) p CF(CF 3 )CH 2 OZ 1 Si(Y 1 ) 3 wherein: Z 1 represents —R 1 —S—R 2 —, —R 1 —S(═O)—R 2 —, or —R 1 —S(═O) 2 —R 2 , wherein R 1 and R 2 independently represent alkylene groups having from 1 to 12 carbon atoms; each Y 1 independently represents a hydrolyzable group; and R fa represents a perfluoroalkyl group having from 1 to 12 carbon atoms, optionally substituted with at least one catenated oxygen atom or —NR 8 —group, wherein R 8 represents a perfluoroalkyl group; p is a number in a range of from 3 to 50; and (b) from 5 to 49 parts by weight of a second polyfluoropolyether silane represented by formula: R fb [R 5 CH 2 OZ 2 Si(Y 2 ) 3 ] 2 wherein: each Z 2 independently represents —R 3 —S—R 4 —, —R 3 —S(═O)—R 4 —, or —R 3 S(═O) 2 —R 4 , wherein R 3 and R 4 independently represent alkylene groups having from 1 to 12 carbon atoms; each Y 2 independently represents a hydrolyzable group; each R 5 independently represents a covalent bond, or —(OR 7 ) b —, wherein each R 7 independently represents a branched perfluoroalkylene group, and each b independently represents a number greater than or equal to one; and R fb represents a perfluoroalkylene group having at least 3 carbon atoms, optionally substituted with at least one catenated oxygen atom or —NR 6 —group, wherein R 6 represents a perfluoroalkyl group, wherein the parts by weight of the first polyfluoropolyether silane and the second polyfluoropolyether silane are based on the total parts of the first polyfluoropolyether silane and the second polyfluoropolyether silane combined.