| abstract |
The present invention relates to water soluble or water swellable polymers containing (a) 25? 35 mol% of recurrent structural unit (s) of formula (1) wherein: r1, r2 are h, methyl or ethyl; a is C 1 -C 12 linear or branched alkylene; and q + is h, nh4 +, li +, na +, k +, ½ ca ++, ½ mg ++, ½ zn ++, ai +++, organic ammonium ions of the formula [hnr5r6r7] +, where r5, r6 and r7 may be h, groups straight or branched alkyl of 1 to 22 c atoms, straight or branched alkenyl, one or more times unsaturated with 2 to 22 c atoms, C 6 -C 22 alkylamidopropyl, linear monohydroxyalkyl of 2 to 10 c atoms or di linear or branched hydroxyalkyl of 3 to 10 c atoms where at least one of r5, r6 and r7 is not h or represents mixtures of these ions, (b) 3 to 8 mol%, of recurrent structural unit (s) (s) of formula (2), wherein r1 is h, methyl or ethyl; x + is h +, nh4 +, li +, na +, k +, ½ ca ++, ½ mg ++, ½ zn ++, ai +++, organic ammonium ions of the formula [hnr5r6r7] +, where r5, r6 and r7 can be h, alkyl groups straight or branched with 1 to 22 c atoms, straight or branched alkenyl, one or more times unsaturated with 2 to 22 c, C 6 -C 22 alkylamidopropyl atoms, linear monohydroxyalkyl with 2 to 10 c atoms or dihydroxyalkyl straight or branched with 3 to 10 c atoms where at least one of r 5, r 6 and r 7 is not h or mixtures thereof; b is straight or branched alkylene group having 1 to 6 c atoms; and n is an integer from 0 to 5; and c is 57 to 72 mol% of a (meth) acrylamide. |