Degradation on polyacrylamides. Part II. Polyacrylamide gels

The stability of polyacrylamide (PAAm) gels, synthesized by free radical polymerization of acrylamide (AAm) and N,N′-methylenebisacrylamide (BIS), was investigated when subjected to thermal and irradiation conditions. The PAAm gels were stable and did not release AAm under fluorescent light. In aqueous solution at 95 °C, a small amount of AAm was observed and it is shown that this is found from the pendant unsaturation of BIS in the gel network. Under UV irradiation, approximately one molecule of AAm is released for every 20,000 repeat monomer units in the gel. Gels were also synthesized from methacrylamide with BIS, AAm with N,N′-methylenebismethacrylamide and AAm with bisacryloyl-piperazine. Their stability is compared to the AAm/BIS gels.