Investigation of the gelation process by in-situ interferometry

An in-situ interferometric technique was established to investigate the gel ation process of poly(acrylic acid) (PAA) gel. The basic principles of the in-situ interferometric technique is illustrated. It can provide sufficient information for a non-destructive and successful investigation throughout the whole gelation process. Moreover, the effect of the photoinitiator conc entration on the gelation process was studied. The polymerization rate of A A increases with increasing the concentration of the photoinitiator. The er ror caused by thermal effects during the gelation process can be neglected.