. . . . . . "Wu-Bin Yuo, Gwo-Yang Chang, Jeng-Yue Wu, Mao-Song Lee, \"Preparation of nylon 6 with alkali metal hypophosphite catalyst and organic phosphite catalyst.\" U.S. Patent US5298594, issued June, 1970."@en . . . . . . . . . . . "Hypophosphite"@en . . . . . . "experimental"@en . . . . . . . . . . .