Polymer substrates formed from carboxy functional acrylamide

Abstract

A polymer substrate, such as a polymer particle, is formed from a carboxyl functional monomer. In an example, the carboxyl functional monomer has a protection group in place of the OH of the carboxyl group. Once the monomer is polymerized, such a protection group can be removed, providing a polymer network with carboxyl functional sites. Such sites can be used to attach other functionality to the polymer substrate.

What is claimed is: 
     
         1 . A compound of the formula: 
       
         
           
           
               
               
           
         
         wherein R 1  is an alkyl group having between 3 and 10 carbons or is a polyether group having between 1 and 10 ether units, wherein R 2  is a linear or branched alkyl group having between 3 and 8 carbons or a silyl group, and wherein R 3  is hydrogen or an alkyl group having between 1 and 6 carbons. 
       
     
     
         2 . The compound of  claim 1 , wherein R 1  is an alkyl group having between 3 and 6 carbons. 
     
     
         3 . The compound of  claim 2 , wherein R 1  is an alkyl group having between 3 and 5 carbons. 
     
     
         4 . The compound of  claim 1 , wherein R 1  is a polyether group having 2 to 6 units. 
     
     
         5 . The compound of  claim 1 , wherein the units of R 1  include ethylene oxide or propylene oxide units. 
     
     
         6 . The compound of  claim 1 , wherein R 2  is a branched alkyl group. 
     
     
         7 . The compound of  claim 6 , wherein R 2  is a branched alkyl group having between 3 and 5 carbons. 
     
     
         8 . The compound of  claim 7 , wherein R 2  is a branched alkyl group having 4 carbons. 
     
     
         9 . The compound of  claim 1 , wherein R 3  is hydrogen. 
     
     
         10 . The compound of  claim 1 , wherein R 3  is a methyl or ethyl group. 
     
     
         11 . A population of particles having a coefficient of variance of not greater than 5% and comprising a polymer derived from polymerization of a compound of the formula: 
       
         
           
           
               
               
           
         
         wherein R 1  is an alkyl group having between 3 and 10 carbons or is a polyether group having between 1 and 10 ether units, wherein R 2  is a linear or branched alkyl group having between 3 and 8 carbons or a silyl group, and wherein R 3  is hydrogen or an alkyl group having between 1 and 6 carbons; and 
         wherein after removal of R 2 , the particle absorbs at least 300 wt % and not greater than 10 6  wt % water based on the weight of the polymer when exposed to water. 
       
     
     
         12 . The population of particles of  claim 11 , wherein the polymer is further derived from the polymerization of protected acrylamide or protected hydroxyalkyl acrylamide with the compound. 
     
     
         13 . The population of particles of  claim 11 , wherein the polymer is further derived from the polymerization of a crosslinker with the compound. 
     
     
         14 . The population of particles of  claim 13 , wherein the crosslinker comprises a diacrylamide. 
     
     
         15 . The population of particles of  claim 14 , wherein the diacrylamide includes N,N′-(ethane-1,2-diyl)bis(2-hydroxyl ethyl)acryl amide, N,N′-(2-hydroxypropane-1,3-diyl)diacrylamide, a protected derivative thereof, or a combination thereof. 
     
     
         16 . The population of particles of  claim 11 , wherein R 1  is an alkyl group having between 3 and 6 carbons. 
     
     
         17 . The population of particles of  claim 16 , wherein R 1  is an alkyl group having between 3 and 5 carbons. 
     
     
         18 . The population of particles of  claim 11 , wherein R 1  is a polyether group having 2 to 6 units. 
     
     
         19 . The population of particles of  claim 11 , wherein the units of R 1  include ethylene oxide or propylene oxide units. 
     
     
         20 . The population of particles of  claim 11 , wherein R 2  is a branched alkyl group.