Patent ID: 8722824

Claim:
A (meth)acrylamide copolymer of general formula (I): wherein R 1 and R 2 , equal to or different from one another, represent a hydrogen radical or C 1 -C 22 alkyl radicals, with the proviso that the sum of the carbon atoms of the two groups R 1 and R 2 be comprised between 8 and 32; x, y and z represent the percentages of the three units inside the polymeric chain deriving from three comonomers (a), (b) and (c), and wherein y is from 0.05 to 2 and z is from 1 to 30 and x+y+z=100; the unit A represents the copolymer of general formula (I) according to: where R 5 , R 6 and R 7 , equal to or different from one another, represent a hydrogen or methyl radical; R 3 and R 4 , equal to or different from one another, represent a C 4 -C 20 hydrocarbon radical, linear or branched, containing a quaternary ammonium group, or one between R 3 or R 4 has the structure: —R 8 —N(R 9 R 10 R 11 ) + X − where R 8 represents a C 2 -C 6 , optionally branched, alkylene radical, and R 9 , R 10 , R 11 , equal to or different from one another, are C 1 -C 4 alkyl radicals; alternatively R 3 and R 4 are bonded together and form a 6-membered cycle containing a quaternary nitrogen of formula: where R 9 and R 10 , equal to or different from one another, are C 1 -C 4 alkyl radicals and X is an organic or inorganic monovalent anion chosen between halides, tetrafluoroborate, hexafluorophosphate, methylsulfate, trifluoromethanesulfonate, benzenesulfonate, p-toluenesulfonate, perchlorate and nitrate.