| abstract |
Novel N-vinyl pyrrolidone/acrylamide/N-alkyl acrylamide terpolymers have the formula:n wherein w is 1 to 80 mole percent, preferably 10 to 70 mole percent; x is 10 to 90 mole percent, preferably 30 to 70 mole percent; and y is 0.1 to 10.0 mole percent, preferably 0.2 to 3.0 mole percent; R is alkyl groups having 6 to 30 carbon atoms, preferably 8 to 18. n The terpolymers are useful as improved viscosification agents for aqueous solutions containing, for example, an acid or a base or a salt. |