Mannich acrylamide polymers

Abstract

Mannich (alk)acrylamide microparticles are produced at high solids contents without a significant increase in bulk viscosity by inverse microemulsion polymerization and provide superior dewatering characteristics.

We claim: .[.1. A method of concentrating dispersion of suspended solids which comprises (a) dewatering a dispersion of suspended solids by adding to said dispersion from about 10 to about 100,000 parts per million of a composition comprising (alk)acrylamide-containing polymeric microparticles, said (alk)acrylamide polymeric microparticles being substituted with at least about 1 mole percent of tertiary aminomethyl groups and having an average particle size of from about 200 to about 4000Å in diameter wherein crosslinking of said polymeric microparticles occurs in said composition, and said polymeric microparticles are effective flocculants in the dewatering of said suspended solids and separating the resultant concentrated dispersion..]..[.2. A method as defined in claim 1 wherein said dispersion comprises a biologically treated suspension..]..[.3. A method as defined in claim 1 wherein said average particle size is from about 300-2000Å in diameter..]..[.4. A method as defined in claim 1 wherein said average particle size is from about 350-2000Å in diameter..]..[.5. A method according to claim 1 wherein said (alk)acrylamide is acrylamide..]..[.6. A method as defined in claim 1 wherein said dispersion comprises paper waste, refinery waste or food waste..]..[.7. A method according to claim 1 
     
        wherein said tertiary aminomethyl groups are quaternized..]..Iadd.8.  In a method of dewatering suspended solids by the addition to said suspended solids of an effective amount of a Mannich (alk)acrylamide-based polymer substituted with at least about 1 mole percent of tertiary aminomethyl groups, which polymer undergoes extensive interpolymer cross-linking, the improvement comprising preparing said polymer in the form of polymer micelles having an average particle size of from about 200 to about 4,000 Å in diameter, said polymer micelles being derived from a microemulsion..Iaddend..Iadd.9. A method as defined in claim 8 wherein said suspended solids comprise a biologically treated suspension..Iaddend..Iadd.10. A method as defined in claim 8 wherein said average particle size is from about 300 to about 2000 Å in diameter..Iaddend..Iadd.11. A method as defined in claim 8 wherein said average particle size is from about 350 to about 1000 Å in diameter..Iaddend..Iadd.12. A method as defined in claim 8 wherein said (alk)acrylamide is acrylamide..Iaddend..Iadd.13. A method as defined in claim 8 wherein said suspended solids comprise paper waste, refinery waste or food waste..Iaddend..Iadd.14. A method as defined in claim 8 wherein said Mannich acrylamide-based polymer is quaternized..Iaddend..Iadd.15. A method as defined in claim 8 wherein the polymer is added to said suspended solids as an aqueous solution..Iaddend..Iadd.16. A method as defined in claim 8 wherein the polymer is added to said suspended solids as an aqueous solution prepared by recovering the polymer from said 
     
     
        polymer micelles and dispersing the polymer into water..Iaddend..Iadd.17. A method as defined in claim 16 wherein the polymer is recovered from the polymer micelles by precipitating the polymer from the polymer micelles, filtering off the resultant solids and drying the solids to recover the polymer..Iaddend..Iadd.18. A method as defined in claim 17 wherein the polymer is precipitated from the polymer micelles by adding the polymer micelles to a solvent selected from isopropanol and acetone..Iaddend..Iadd.19. A method as defined in claim 8 wherein the polymer solids content of the microemulsion is greater than 10 percent by weight..Iaddend..Iadd.20. A method as defined in claim 8 wherein the amount of polymer added to said suspended solids is about 10 to about 100,000 parts per million..Iaddend..Iadd.21. In a method of dewatering suspended solids by the addition of said suspended solids of an effective amount of a Mannich (alk)acrylamide-based polymer substituted with at least about 1 mole percent of tertiary aminomethyl groups, which polymer undergoes extensive interpolymer cross-linking, the improvement comprising preparing said polymer in the form of polymer micelles derived from a microemulsion, said polymer micelles having an average particle size of from about 200 to about 4,000 Å in diameter, and thus preventing said cross-linking..Iaddend..Iadd.22. The method of claim 21 wherein the polymer micelles are formed by: a. admixing i. an aqueous solution of at least one (alk)acrylamide monomer and, optionally, at least one ethylenically unsaturated comonomer;   ii. an oil solution comprising at least one hydrocarbon liquid; and   iii. an effective amount of surfactant or surfactant mixture so as to form an inverse microemulsion     b. subjecting the inverse microemulsion obtained in step (a) to polymerization conditions; and   c. reacting the polymerized polymer obtained in step (b) with an effective amount of a formaldehyde and a secondary amine or a complex thereof; and   
     
     
       d. optionally, quaternizing the resultant polymer..Iaddend..Iadd.23.  The method of claim 21 wherein the polymer micelles are formed by: a. reacting i. at least one (alk)acrylamide monomer and, optionally, at least one ethylenically unsaturated comonomer; and   ii. a formaldehyde and a secondary amine or a complex thereof in aqueous solution to produce a Mannich (alk)acrylamide monomer;     b. admixing i. an aqueous solution of at least one said (alk)acrylamide monomer and optional comonomer obtained in (a);   ii. an oil solution comprising at least one hydrocarbon liquid; and   iii. an effective amount of surfactant or surfactant mixture so as to form an inverse microemulsion;     c. subjecting the inverse microemulsion obtained in step (b) to polymerization conditions; and   d. optionally, quaternizing the resultant polymer..Iaddend..Iadd.24. The method of claim 21 wherein the polymer micelles are formed by:   a. admixing i. an aqueous solution comprising an (alk)acrylamide monomer and, optionally, at least one ethylenically unsaturated comonomer a formaldehyde and a secondary amine or a complex thereof;   ii. an oil solution comprising at least one hydrocarbon liquid; and   iii. an effective amount of surfactant or surfactant mixture, so as to form an inverse microemulsion;     b. subjecting the inverse microemulsion obtained in step (a) to polymerization conditions and allowing the formaldehye and secondary amine to react with (alk)acrylamide amide groups; and   c. optionally, quaternizing the resultant polymer..Iaddend..Iadd.25. The method of claim 21, 22, 23 or 24 wherein the polymer micelles have an average particle size of from about 300 to about 2000 Å in diameter..Iaddend..Iadd.26. The method of claim 21, 22, 23 or 24 wherein the polymer micelles have an average particle size of from about 350 to about 1000 Å in diameter..Iaddend..Iadd.27. The method of claim 21 wherein the polymer is added to said suspended solids as an aqueous solution prepared by inverting the polymer micelles into water, optionally in the presence of a breaker surfactant..Iaddend..Iadd.28. The method of claim 21 wherein the polymer is added to said suspended solids as an aqueous solution prepared by recovering the polymer from the polymer micelles and dispersing the polymer into water..Iaddend..Iadd.29. The method of claim 22, 23 or 24 wherein said (alk)acrylamide monomer comprises acrylamide, said formaldehyde composes formalin, and said secondary amine comprises dimethylamine..Iaddend..Iadd.30. The method of claim 21 wherein the amount of polymer added to said suspended solids is about 10 to 10,000 parts per million..Iaddend.