Reduced byproduct polyamine-epihalohydrin resins

Abstract

Processes for rendering a polyamine-epihalohydrin resin storage stable, including processes that prepare a storage stable resin and/or processes that treat resins. A composition containing a polyamine-epihalohydrin resin which includes CPD-forming species can be treated with at least one agent under conditions to at least one of inhibit, reduce and remove the CPD-forming species to obtain a reduced CPD-forming resin so that a composition containing the reduced CPD-forming polyamine-epihalohydrin resin when stored for 2 weeks at 50° C., and a pH of about 2.5 to 3.5 contains less than about 250 ppm dry basis of CPD. The invention is also directed to a gelation storage stable reduced CPD-forming resin so that a composition containing the reduced CPD-forming polyamine-epihalohydrin resin, when stored at pH 1 for 24 hours at 50° C. and measured at 24 hours, produces less than about 1000 ppm dry basis of CPD. A paper product containing the storage stable polyaminopolyamide-epihalohydrin resin, when corrected for adding at about a 1 wt % addition level of the polyaminopolyamide-epihalohydrin resin, contains less than about 250 ppb of CPD. Moreover, a resin can be prepared starting from a prepolymer having a low acid number or low concentration of acid end groups. The invention is also directed to papers containing the resins.

1 . A storage stable polyaminopolyamide-epihalohydrin resin, 
 said resin when stored as an aqueous composition containing the resin, and when stored at pH 1 for 24 hours at 50° C. and measured at 24 hours, produces less than about 1000 ppm dry basis of CPD;    said resin being produced from a reaction of a) polyaminoamide prepolymer having an acid functionality less than about 0.5 milliequivalents/dry gram of prepolymer and b) epihalohydrin,    said prepolymer being end-capped prior to reaction with epihalohydrin by reaction with an endcapping agent.    
     
     
         2 . The resin of  claim 1  wherein the endcapping agent is selected from 
 (i) a monofunctional amine,    (ii) a monofunctional carboxlic acid, or    (iii) a monofunctional carboxylic ester.    
     
     
         3 . The resin of  claim 1  wherein the endcapping agent is a monofunctional amine selected from the class consisting of monofunctional primary amines and monufunctional secondary amines.  
     
     
         4 . The resin of  claim 1  wherein the endcapping agent is a monofunctional amine selected from butylamine, monoethanolamine, cyclohexylamine, 2-methylcyclohexylamine, 3 methylcyclohexylamine, 4-methylcyclohexylamine, benzylamine, isopropanolamine (i.e., monoisopropanolamine), mono-sec-butanolamine, 2-amino-2-methyl-1-propanol, tris(hydroxymethyl)aminomethane, tetrahydrofurfurylamine, furfurylamine, 3-amino-1,2-propanediol, 1-amino-1-deoxy-D-sorbitol, 2-amino 2-ethyl-1,3-propanediol, less preferred, diethylamine, dibutylamine, diethanolamine, di-n-propylamine, diisopropanolamine, di-sec-butanolamine, and N-methylbenzylamine.  
     
     
         5 . The resin of  claim 1  wherein the endcapping agent is a monofunctional carboxylic acid or ester thereof selected from benzoic acid, 2-hydroxybenzoic acid, 3-hydroxybenzoic acid, acetic acid, phenylacetic acid, propionic acid, butyric acid, valeric acid, caproic acid, caprylic acid, 2-ethylhexanoic acid, oleic acid, ortho-toluic acid, meta-toluic acid, para-toluic acid, ortho-methoxybenzoic acid, meta-methoxybenzoic acid, para-methoxybenzoic acid, methyl acetate, ethyl acetate, methyl benzoate, ethyl benzoate, methyl propionate, ethyl propionate, methyl butyrate, ethyl butyrate, methyl phenyl acetate, and ethyl phenyl acetate.  
     
     
         6 . Paper or paper pulp treated with the resin of  claim 1 .  
     
     
         7 . Paper or paper treated with the resin of  claim 2 .  
     
     
         8 . Paper or paper treated with the resin of  claim 3 .  
     
     
         9 . Paper or paper treated with the resin of  claim 4 .  
     
     
         10 . Paper or paper treated with the resin of  claim 5.