A modified kinetic model is developed which captures how the cross-linked network structure and its evolution in loosely cross-linked polymers affects the polymerization kinetics. In our previous work, diffusion-controlled kinetics has been modeled through the change in free volume of the system as monomer converts to polymer. 1,2 Here, the additional effect of the resistance caused by the need to diffuse through the cross-linked network is incorporated into a model of the polymerization kinetics. With this model, the effects of cross-linking and cyclization observed in experimental systems are predicted. The model quantitatively predicts experimental results for varying concentrations of 1,4-cyclohexanediol dimethacrylate and 1,2-cyclohexanediol dimethacrylate copolymerized with methoxy ethyl methacrylate.