US Patent 7608665 Temporary wet strength resin for paper applications

A thermosetting resin comprising a reacted A) first partially crosslinked glyoxalated polymer comprising a reacted (i) first polyacrylamide backbone and (ii) a first glyoxal component; and B) a second crosslinked glyoxalated polymer comprising a reacted (i) second polyacrylamide backbone and (ii) a second glyoxyal component; such that the first polyacrylamide backbone has a molecular weight that is less than the molecular weight of the second polyacrylamide backbone; and the first polyacrylamide backbone and the second polyacrylamide backbone have a weight ratio ranging from 75:25 to 95:5. Methods for making and using the resin. Fibrous substrates made with the resin.