Proton T1ρ data obtained by CP/MAS solid-state 13C NMR at 100.56 MHz for different polyacrylate networks were correlated with their mechanical properties in order to determine the best mixture in terms of stress-at-break (σ), Young's modulus of elasticity (Y), and homogeneity of the monomers that are forming the solid network. The mixtures were formed by the photopolymerization of 40% trimethylolpropane triacrylate (TMPTA), 40% dipentaerythritol pentaacrylate (DPHPA), and 20% of a monomer from a series of poly(ethylene glycol) and poly(ethylene) dimethacrylate. Proton T1ρ's in networks were not quite averaged to a single value by spin diffusion as in polymer blends, indicating extensive intermixing of TMPTA and DPHPA in forming the network, but with phase separation between the dimethacrylate homopolymer and the rest of the network that is dependent on the laser power. The stress-at-break and the Young's modulus of elasticity were determined for each of the mixtures at different values of the laser power used for the polymerization. © 1996 John Wiley & Sons, Inc.