Process for cross-linking polymers

Abstract

There is disclosed an improved process for cross-linking polymers by contacting said polymers with a cross-linking agent at an elevated temperature. The improvement comprises using as the cross-linking agent a compound of the formula ##STR1## wherein R.sub.1 and R.sub.2 are independently selected from the group consisting of alkyl groups having 1-22 carbon atoms, alkenyl groups having 2-22 carbon atoms, cyclohexyl groups having 6-20 carbon atoms, phenyl groups having 6-20 carbon atoms, aralkyl groups having 7-20 carbon atoms, alkyloxy groups having 1-22 carbon atoms, alkenyloxy groups having 2-22 carbon atoms, and cyclohexyloxy groups having 6-20 carbon atoms, all of which groups may be substituted or unsubstituted; R.sub.3 is selected from the group consisting of hydrogen, alkyl groups having 1-22 carbon atoms, alkenyl groups having 2-22 carbon atoms, cyclohexyl groups having 6-20 carbon atoms, phenyl groups having 6-20 carbon atoms, aralkyl groups having 7-20 carbon atoms, and ##STR2## wherein R.sub.4 is independently selected from the same group as R.sub.1 and R.sub.2 as defined above, all of which groups may be substituted or unsubstituted; provided that when R.sub.3 is hydrogen, R.sub.1 represents an alkyloxy, alkenyloxy or cyclohexyloxy group as defined above.