Method for curing polymers containing one or more carboxy or anhydride functions by means of polymers having hydroxyamide groups, and compositions

DETAILED DESCRIPTION We claim: 1.
A method of curing addition polymers having carboxy groups, carboxylic anhydrides or salts of said carboxy groups which comprises the steps of (1 ) mixing said polymer with a different addition polymer containing two or more pendant .
beta.
-hydroxyalkyl amide groups of the formula: ##STR10## wherein R.
sup.
1 is hydrogen, alkyl having 1 to 5 carbon atoms, or hydroxyalkyl having from 1 to 5 carbon atoms; R.
sup.
2 and R.
sup.
3 are the same or different radicals selected from hydrogen, straight or branched chain alkyl having from 1 to 5 carbon atoms, or one of the R.
sup.
2 and one of the R.
sup.
3 radicals joined together with the carbon atoms to which they are attached form cycloalkyl and (2) heating the mixture at a temperature of from about 125.
degree.
to 400.
degree.
C.
until a cured polymer is obtained.
2.
A method according to claim 1 wherein the .
beta.
-hydroxyalkyl amide groups are present in a minor proportion in an addition copolymer containing the residues of polymerized ethylenically unsaturated monomers, and said hydroxyalkylamide groups have the formula: ##STR11## wherein R.
sup.
1 is hydrogen, alkyl having 1 to 5 carbon atoms, or hydroxyalkyl having 1 to 5 carbon atoms, and R.
sup.
3 is selected from hydrogen and straight or branched chain lower alkyl radicals having from 1 to 5 carbon atoms.
3.
The method of claim 2 in which R.
sup.
1 is ##STR12## and R.
sup.
3 is --H or --CH.
sub.
3.
4.
The method of claim 3 in which the carboxy, carboxylic acid salt groups, or carboxylic acid anhydride groups are in an addition copolymer of ethylenically unsaturated monomers, and the copolymer is prepared with a minor proportion of at least one monomer selected from acrylic acid, methacrylic acid, crotonic acid, maleic acid, 2-methyl maleic acid, itaconic acid, 2-methyl itaconic acid, .
beta.
-methylene glutaric acid, maleic anhydride, itaconic anhydride, acrylic anhydride, and methacrylic anhydride.
5.
The method of claim 4 in which the ratio of salt, carboxy or anhydride functional groups to hydroxy functional groups is between about 0