Analysis and modeling of PVTX diagram of an unsaturated polyester resin, thermoplastic additive, and mineral fillers blend

We studied the dynamic curing of a polymer blend containing an unsaturated polyester prepolymer, styrene, and a saturated polyester as a low-profile thermoplastic additive during heating from 40 to 160degreesC with a constant rate (4 or 10 K/min). This work was performed by means of a homemade dilatometer that simultaneously determined conversion degree, volume, pressure, and temperature. The various phenomena inducing volume change were identified and then separated (thermal expansion, shrinkage, and shrinkage compensation). A model based on physical consideration was built that allowed an accurate fit of the experimental results. The influence of the pressure on all this phenomena was summarized and quantified. (C) 2003 Wiley Periodicals, Inc.