Water-soluble cationic copolymers and their use as drainage retention aids in papermaking processes
AssigneeW. R. Grace & Co.-Conn.
InventorsLawrence L. Kuo, Roger Y. Leung, Kenneth S. Williams
Life of this patent
Estimating the term…
Abstract
A method of preparing paper or paper board product from an aqueous pulp suspension comprising adding to the suspension an effective amount of a drainage retention aid composition of a) microparticles and b) at least one water soluble cationic polymer selected from a water soluble cationic copolymer composed of the polymerization reaction of an N-vinylamide with at least one cationic quaternary amine monomer. The copolymers of this invention are useful as useful as drainage/retention aids in pulp and papermaking operations.
Claims18
A method of preparing paper or paper board product from an aqueous pulp suspension comprising adding to the suspension an effective amount of a drainage retention aid composition of a) microparticles having a negative, positive or amphoteric surface charge;
- and b) at least one water soluble cationic polymer selected from
- (i) a water soluble cationic copolymer (I) composed of the polymerization reaction of an N-vinylamide having the general formula:
- ##STR20## with at least one cationic quaternary amine monomer of the general formula:
- ##STR21## wherein Y represents ##STR22## or (ii) a water soluble cationic copolymer (II) having the general formula:
- ##STR23## wherein Z represents ##STR24## or residual groups of --CH.sub.2 N.sup..sym. (R.sup.4 R.sup.5)CH.sub.2 CH.dbd.CH.sub.2 X.sup..crclbar. or mixtures thereof:
- and for Y and Z of copolymer I and II, n is 1 to 5, R.sup.1, R.sup.2 and R.sup.3 are independently selected from the group consisting of H or C.sub.1 to C.sub.3 alkyl;
- R.sup.4, R.sup.5 and R.sup.6 are independently C.sub.1 to C.sub.3 alkyl;
- and X is a halide, hydroxyl or alkylsulfate anion;
- and wherein x, y, and q represent molar percents of monomeric units in the copolymer and q is 1 to 99 mol %, the sum of x+y+q is 100 mol % and the molar ratio of x to y is from 0.033 to 2.8, or mixtures thereof, and n is 1 to 5;
- R.sup.1, R.sup.2 and R.sup.3 are independently selected from H or C.sub.1 -C.sub.3 alkyl;
- R.sup.4, R.sup. 5 and R.sup.6 are independently selected from C.sub.1 -C.sub.3 alkyl;
- X is a halide, hydroxyl or methylsulfate anion such that the molar ratio of N-vinylamide to cationic quaternary amine monomers is 1:99 to 99:1 and the molar ratio of x to y is from 0 to 10.
Dependencies are inferred from the claim text.