PHYSICAL REVIEW E, cilt.77, sa.5, 2008 (SCI-Expanded)
Real-time fluorescence measurements have been developed for measuring the fractal dimension d(f) and critical exponents gamma and beta simultaneously during the sol-gel transition of acryiamide bisacrylamide crosslinking copolymerization. We observed that d(f) passes through a minimum value of similar to 2.5 at a critical time t(c) and crossover to 3 above it. The exponents gamma and beta, measured at t(c), were found to be around 1.8 and 0.45, respectively. All parameters d(f), beta, and gamma measured at the critical point t(c) agree with three-dimensional percolation results.