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Dynamic light scattering was used to investigate the dynamics of sodium poly(styrene sulfonate) and fully neutralized poly(acrylic acid) gels as a function of the degree of swelling and weight ratio of cross-linking agent. It was shown that the collective diffusion coefficient increases with increasing degree of swelling and that the diffusion coefficient shows stronger concentration dependence than predicted by scaling arguments. For gel samples measured at the swelling equilibrium, the diffusion coefficient increases with increasing gel concentration for both gel systems.

Using the integral and differential turbidity ratio methods, processes occurring during the continuous heating, equilibration and cooling of the Phema gel have been characterized. Microseparated particles were shown to be responsible for the turbidity changes below 40°C, even if not exclusively. The role of large scatterers called fluctuation microregions in the individual periods has been discussed.

Using the integral and differential turbidity ratio methods it was recognized that a special type of optical heterogeneities called fluctuation microregions is probably responsible for the small changes observed in the turbidity of the transparent gel of poly (2-hydroxyethyl methacrylate) caused by rising temperature and swelling (in butanol) . Their dynamics and possible mechanisms are discussed.

The isothermal curing process of the system diglycidyl ether of Bisphenol A/poly (oxypropylene) diamine (Jeffamine D-400) without and in the presence of solvent (Diglyme) was investigated by Brillouin spectroscopy for the stoichiometric amounts of epoxide and amine groups. The spectroscopic data have been explained in terms of the relaxing viscosity model in the former case and by the scattering of phonons by stationary heterogeneities in the latter one. It is suggested that these heterogeneities may be small air bubles released during curing and frozen in due to the high viscosity at and above the gel point.

Quasielastic light scattering measurements on transparent poly (2-hydroxyethyl methacrylate) (PHEMA) gels were performed under temperature equilibrium conditions at several temperatures from 40 to 80°C. All observed correlation functions departed from the single exponential decay with a long-time limit. The asymptotic value relaxation frequency Γa decreased steeply with decreasing temperature. The observed temperature dependence of Γa is interpreted as resulting from polymer fluctuations near the glass transition of weakly swollen PHEMA gels.

Measurements of composite autocorrelation functions extending over a broad time range on semidilute theta solutions of polystyrene in cyclohexane are reported. Three mathematical methods were used to obtain the corresponding distribution functions of decay times, F(τ). Results of the different methods are in mutual agreement. It is found that F(τ) consists of several separated bands. The shortest and longest decay times have been extracted from F(τ) and, on the basis of their concentration and angular dependences, attributed to the gel mode and reptation process, respectively.

The effect of curing on the fluorescence intensity of 1,6-diphenyl-1,3,5-hexatriene (DPH) and 9,10-dimethylanthracene (DMA) was studied using two epoxide/amine systems. In the system diglycidyl ether of Bisphenol A (DGEBA)/1,3-diaminopropane the fluorescence intensity of DMA, If, increases with increasing conversion of epoxy groups; this is explained by means of a dynamic model of fluorescence quenching by dissolved molecular oxygen. Contrariwise, in the other system under study, DGEBA/poly (oxypropylene) diamine (JeffamineR D-400), If of the DPH probe decreases, which is interpreted by using the model of static fluorescence quenching. Both effects are suggested for use in the cure monitoring of epoxy resins.