The elastic response in polymeric gels is studied by means of a percolation dynamic model. By numerical simulations the fluctuations in the gyration radius and in the center-of-mass motion of the percolating cluster are determined. Their scaling behavior at the gelation threshold gives a critical exponent for the elastic modulus $f\sim 2.5\pm 0.1$ in agreement with the prediction $f=d\nu .$

• Received 7 July 2001

DOI:https://doi.org/10.1103/PhysRevE.65.041803