| abstract |
The present invention provides for a composition comprising a siloxane having the formula:n nM 1 DM 2 n nwhereinn nM 1 =(R 1 )(R 2 )(R 3 )SiO 1/2 ;n nM 2 =(R 4 )(R 5 )(R 6 )SiO 1/2 andn nD=(R 7 )(Z)SiO 2/2 n nwhere R 1 , R 2 , R 3 R 4 , R 5 , R 6 and R 7 are each independently selected from the group consisting of 1 to 4 carbon monovalent hydrocarbon radicals, aryl, and a hydrocarbon group of 4 to 9 carbons containing an aryl group; Z is a pendant hydrophilic ionic group selected from the group consisting of R 8 —R A , R 9- R C , and R 10 —R Z ; R A being an anionic substituent, R C a cationic substituent or R Z a zwitterionic substituent on the D group wherein said siloxane has an enhanced resistance to hydrolysis at a pH below 6 or a pH above 7.5. |