High molecular weight compact structured polymers, methods of making and using

Abstract

A structured water soluble polymer produced by polymerization of amine-containing monomers or pre-formed polymers is described. Various structured polymers are prepared and characterized. The structured polymers are particularly valued in the papermaking industry.

1 . A water-soluble structured polymer, which is the product of the polymerization reaction of monomers comprising one or more amine-containing groups, selected from: 
 a. an ethylenically unsaturated primary, secondary, or tertiary amine and mixtures thereof,    b. a pre-formed polymer comprising a secondary or tertiary amine; and    c. optionally, at least one of acrylamide or methacrylamide;    wherein the structured polymer has a weight-average molecular weight of from about 100,000 to about 5,000,000; an apparent conformation coefficient of less than or equal to about 0.40 in sodium nitrate solution having a pH of about 3; and a greater than or equal to about 80% solubility as determined by SEC/MALLS.    
     
     
         2 . The structured polymer of  claim 1 , wherein the solubility is equal to or greater than about 90% as determined by SEC/MALLS.  
     
     
         3 . The structured polymer of  claim 1 , wherein the structured polymer is characterized by a weight-average molecular weight of from about 100,000 to about 3,000,000.  
     
     
         4 . The structured polymer of  claim 1 , wherein the polymer is characterized by a weight-average molecular weight of from about 500,000 to about 2,000,000.  
     
     
         5 . An improved dry strength additive for paper comprising a structured polymer of  claim 1 .  
     
     
         6 . The structured polymer of  claim 5 , which comprises, as a copolymer component or copolymer components polymerizing: 
 a. acrylamide; and    b. one or more of an ethylenically unsaturated amine monomer of formula (I):      H 2 C═CR 1 -C(O)-A-(CH 2 ) m NR 2 R 3      wherein R 1  is hydrogen or a linear or branched saturated or unsaturated alkyl group of 1 to 5 carbons; 
 A is 0 or; NR 4 , wherein R 4  represents hydrogen or an alkyl group of from 1 to 5 carbons;  
 m is 1, 2, 3, or 4; and  
 R 2  and R 3  are independently hydrogen, linear or branched saturated or unsaturated alkyl group of 1 to 5 carbons, or R 2  and R 3  together with the nitrogen atom to which they are attached form a 5- or 6-membered ring optionally containing 1 or 2 additional heteroatoms selected from N, O or S; and salts thereof.  
   
     
     
         7 . The structured polymer of  claim 6 , which comprises, as a copolymer component or copolymer components polymerizing acrylamide with one or more compounds of formula (1), wherein A represents oxygen or NH and/or R 1  represents hydrogen or methyl or salts thereof.  
     
     
         8 . The structured polymer of  claim 5 , which comprises, as a copolymer component or copolymer components polymerizing: 
 a) acrylamide; and    b) one or more ethylenically unsaturated monomer selected from the group consisting of dimethylaminoethylmethacrylate (DMAEM), dimethylaminoethylacrylate (DMAEA), dimethylaminopropyl methacrylamide (DMAPMA), and dimethylaminopropyl acrylamide (DMAPAA) and salts thereof.    
     
     
         9 . The structured polymer of  claim 5 , which comprises, as a copolymer component or copolymer components polymerizing a pre-formed polymer to which acrylamide has been grafted.  
     
     
         10 . The structured polymer of  claim 9 , wherein the pre-formed polymer is poly(amidoamine) or DADMAC/DMAPMA copolymer and salts thereof.  
     
     
         11 . The structured polymer of  claim 5  which comprises, as a copolymer component or copolymer components polymerizing monoallylamine (MAA), diallyamine, and triallylamine and mixtures thereof.  
     
     
         12 . A process for preparing a structured polymer of  claim 1 , wherein the polymer is derived from at least one amine monomer composition contained within a reaction mixture prepared by: 
 a) providing an aqueous solution of about >1 mole % ethylenically unsaturated amine monomer based on total mer units present in the final polymer;    b) initiating polymerization of the amine monomer with an oxidant of greater than about 1 mole % based on total mer units in the final polymer at a temperature of below about 60 C at a rate sufficient to obtain the desired structured polymer as measured by SEC/MALLS and;    c) adjusting the pH of the solution during polymerization to at least about 4 or above; and    d) recovering the resulting structured amine-containing polymer.    
     
     
         13 . The process of  claim 12 , wherein the oxidant is a persulfate.  
     
     
         14 . The process of  claim 13 , wherein the oxidant, the amine monomer and chain transfer agent are added to the polymerization reaction in either a semi-continuous or continuous manner during polymerization.  
     
     
         15 . A process for preparing the structured dry strength polymer of  claim 5 , wherein the polymer is derived from polymerizing an amine monomer composition contained within a reaction mixture prepared by: 
 a) providing an aqueous solution of about greater than about 1% mole percent of ethylenically unsaturated amine monomer of  claim 5 , based on the total moles of mer units in the polymer, and salts thereof;    b) greater than about 50% mole percent acrylamide, based on the total moles of mer units present in the final polymer;    c) initiating polymerization with an oxidant added in an amount of about 1-5 mole percent, based on the total moles of mer units in the polymer;    d) adjusting the pH of the solution during polymerization to at least about 4 or above, and    e) recovering the resulting structured polymer and salts thereof.    
     
     
         16 . The process of  claim 15 , wherein the ethylenically unsaturated amine monomer is added in a semi-batch addition.  
     
     
         17 . The process of  claim 15 , wherein the oxidant is a persulfate.  
     
     
         18 . A process for preparing a structured polymer of  claim 9 , wherein the polymer is derived from copolymer component Or copolymer components within a reaction mixture prepared by: 
 a) Providing an aqueous solution of a pre-formed polymer comprising a secondary or tertiary amine;    b) Mixing with acrylamide monomer such that the amine to acrylamide mole ratio is greater than one mole percent;    c) Initiating polymerization of the acrylamide monomer with an oxidizing initiator at pH greater than seven and temperature below 60 C    d) Recovering the resulting structured amine-containing -polymer.    
     
     
         19 . The process of  claim 18 , wherein the pre-formed polymer is poly(amidoamine) or DADMAC/DMAPMA copolymer and salts thereof.  
     
     
         20 . The process of  claim 18 , wherein the oxidant is a persulfate.  
     
     
         21 . The process of  claim 18 , further comprising a chain transfer agent added to the polymerization reaction in either a semi-continuous or continuous manner during polymerization.  
     
     
         22 . A process for improving the internal dry strength of paper comprising treating an aqueous suspension of papermaking fibers with a structured polymer, wherein the structured polymer is characterized by: 
 a) a weight-average molecular weight of from about 100,000 to about 5,000,000;    b) an apparent conformation coefficient of less than or equal to 0.40 in 0.1 M sodium nitrate solution having a pH of about 3; and    c) a greater than or equal to 80% solubility as determined by SEC/MALLS;    wherein the resulting structured polymer is derived from copolymer component or copolymer components comprising (i) optionally acrylamide or methacrylamide; (ii) an amine-containing group selected from the group consisting of an ethylenically unsaturated primary, secondary, or tertiary amine and mixtures thereof; or (iii) a pre-formed polymer comprising a secondary or tertiary amine.    
     
     
         23 . A dry strength additive of  claim 5 , wherein an effective amount of the polymer ranges from about 0.1 lb/tn to about 30 lb/tn of said additive per ton of finished paper.  
     
     
         24 . A dry strength additive of  claim 5 , wherein an effective amount of said polymer ranges from about 0.5 lb/tn to about 20 lb/tn of said additive per ton of finished paper.  
     
     
         25 . A dry strength additive according to  claim 5 , wherein an effective amount of said polymer ranges from about 0.5 lb/tn to about 6 lb/tn of said additive per ton of finished paper.  
     
     
         26 . A method of increasing the dry strength of a paper material wherein one or more structured polymer s according to  claim 5  is applied to or incorporated into the papermaking process.