Compatibility versus reaction diffusion: Factors that determine the heterogeneity of polymerized adhesive networks.

Objectives: Heterogeneity and phase separation during network polymerization is a major issue contributing to the failure of dental adhesives. This study investigates how the ratio of hydrophobic crosslinkers to hydrophilic comonomer (C/H ratio), as well as cosolvent fraction (ethanol/water) influences the degree of heterogeneity and proclivity for phase separation in a series of model adhesive formulations.

Methods: Twelve formulations were investigated, with 4 different C/H ratios (7:1, 2.