The structures of partial hydrolysis polyacrylamide samples crosslinked before and after by trihydroxymethyl phenol were characterized by 13C solid nuclear magnetic resonance (NMR) spectroscopy. The structures forming during self-crosslinking between hydroxymethyls and crosslinking between hydroxymethyl and primary amine were generated after reaction means two kinds of reactions were occurred. In further tracing test of infrared spectrometry (IR) and X-ray electron spectroscopy (XPS)

the results of quantificational calculation demonstrated that the increase of second amide group is correspond to decrease of the primary amide group and about 50%～60% primary amide groups participated crosslinking. Moreover

the crosslinking rate between hydroxymethyl and primary amine is greater than that between hydroxymethyls. On the basis of above results

a crosslinking mechanism between trihydroxymethyl phenol and partial hydrolysis polyacrylamide was put forwarded.