An innovative method to control shrinkage in polymer blends, by using N,N-dimethyl-p-toluidine to produce phase separation in an acrylic system, was applied to synthesize polymer blends from polymethyl methacrylate (PMMA) and polytriethylene glycol dimethacrylate (PTEG-DMA). The morphology of several compositions, as analyzed by scanning electron microscopy, reveals microdomains as a function of the specific composition, in contrast to conventional MMA-TEGDMA copolymers synthesized by thermal decomposition of benzoyl peroxide, used here as reference materials. Micro-Raman and DSC analyses were also carried out to support the electron microscopy results as well. (C) 2003 Wiley Periodicals, Inc.