Transition between Phantom and Affine Network Model Observed in Polymer Gels with Controlled Network Structure

The elastic moduli of elastomeric materials are predicted by the affine or phantom or junction affine network models. Although these models are often used, we do not know the requirement conditions for each model or even the validity of each model. The validation of these models is difficult because of the network heterogeneity. In this study, we tried to evaluate these models using Tetra-PEG gel, which has extremely homogeneous network structure. We performed the stretching and tearing tests, and for the first time, observed the transition between the phantom and affine network models around the overlapping concentration of prepolymers.