PHASE MISCIBILITY IN OIL RESIN MIXTURES - A STUDY BY FTIR AND THERMOMECHANICAL ANALYSIS/

Quantitative infrared analysis in the carbonyl region with a simple cu rve-fitting procedure and thermomechanical measurements were used to a nalyse critical behaviours in naturally aged oil/resin mixtures coveri ng a wide range of composition, The results are discussed on the basis of a comparative study performed with fresh mixtures of the same comp osition, used as standards, and a phase miscibility analysis. Thermome chanical measurements give macroscopic evidence for phase segregation in naturally aged mixtures with a resin component content strictly bel ow 50%, while above this threshold the basic components are totally in volved in the formation of a stable mixed oil/resin phase. At the mole cular scale, infrared measurements appear to be sensitive to the subse quent oil/resin interaction in aged mixtures which appears to develop at the first stage of the mixing.