Hydrophobic polymers and their use in preparing cellulosic fiber compositions

1 . A method of improving retention and drainage in a papermaking process wherein the improvement comprising adding to a papermaking slurry, a water compatible hydrophobic polymer.

2 . The method of claim 1 wherein the water compatible hydrophobic polymer is a synthetic copolymer that contains at least one hydrophobic monomer.

3 . The method of claim 2 wherein the synthetic copolymer is formed from at least one monomer comprising at least one hydrophobic monomer selected from lauryl acrylate and octylacrylamide.

4 . The method of claim 2 wherein the synthetic copolymer is formed from at least one monomer comprising at least one non-ionic monomer selected from acrylamide, methacrylamide, N,N-dialkylacrylamides, N-alkylacrylamides, N-vinyl methacetamide, N-vinyl methylformamide, and N-vinyl pyrrolidone.

5 . The method of claim 4 wherein the synthetic copolymer is formed from monomers further comprising at least one anionic monomer selected from the free acid or salt of: acrylic acid; methacrylic acid, maleic acid; itaconic acid; acrylamidoglycolic acid; 2-acrylamido-2-methyl-1-propanesulfonic acid; 3-allyloxy-2-hydroxy-1-propanesulfonic acid; styrenesulfonic acid; vinylsulfonic acid; vinylphosphonic acid; and 2-acrylamido-2-methylpropane phosphonic acid.

6 . The method of claim 4 wherein the synthetic copolymer is from monomers further comprising at least one cationic monomer selected from the free base or salt of: diallyldimethylammonium halide; dialkylaminoalkyl (meth)acrylate, diethylaminoethyl (meth)acrylate, dimethyl aminopropyl (meth)acrylate, 2-hydroxydimethyl aminopropyl (meth)acrylate, aminoethyl (meth)acrylate, N,N-dimethylaminoethylacrylamide, and acryloyloxyethyl trimethyl ammonium chloride.

7 . The method of claim 5 wherein at least one anionic monomer is selected from the free acid or salt of: acrylic acid, styrenesulfonic acid, or 2-acrylamido-2-methyl-1-propanesulfonic acid.

8 . The method of claim 1 further comprising adding a siliceous material to the paper making slurry.

9 . The method of claim 8 wherein the siliceous material is selected from the group consisting of silica based particles, silica microgels, amorphous silica, colloidal silica, anionic colloidal silica, silica sols, silica gels, polysilicates, polysilicic acid, and combinations thereof.

10 . The method of claim 2 wherein the water compatible hydrophobic copolymer comprises anionic monomers.

11 . The method of claim 4 wherein the non-ionic monomer comprises acrylamide.

13 . The method of claim 2 wherein the water compatible hydrophobic polymer comprises cationic monomers.

14 . A composition comprising a water compatible hydrophobic polymer and cellulosic fiber.

15 . The method of claim 1 wherein the water compatible hydrophobic polymer is selected from the group consisting of a hydrophobic alkali swellable emulsion, an ethoxylated urethane polymer, a fluorinated polymer, a hydrophobically modified natural polymer or mixtures thereof.

16 . The method of claim 2 wherein the hydrophobic monomer is present in the polymer in an amount of less than about 5% on a molar basis.

17 . The method of claim 2 wherein the hydrophobic monomer is present in the polymer in an amount of less than about 2% on a molar basis.

18 . The method of claim 1 wherein the water compatible hydrophobic polymer is added to the papermaking slurry in an amount of from about 0.005 kg to about 5 kg of active polymer per metric ton of cellulosic pulp.

19 . The method of claim 1 wherein the water compatible hydrophobic polymer is added to the papermaking slurry in an amount of from about 0.025 kg to about 2.5 kg of active polymer per metric ton of cellulosic pulp.

20 . A method of improving retention and drainage in a papermaking process wherein the improvement comprising adding to a papermaking slurry, a water compatible hydrophobic polymer, wherein the water compatible hydrophobic polymer comprises acrylamide, acrylic acid and octylacrylamide.