Differential Scanning Calorimetry (DSC) Study of a New Class of Physically-Thickened Polymer Blends for the Manufacture of Thermoset Moulding Compound
May 21st, 2001
Paper to the 17th Annual Meeting of the Polymer Processing Society, Montreal, Canada
M Esfandeh with S F Bush and J M Methven
Abstract
This paper describes a Differential Scanning Calorimetry (DSC) study of a new class of thermosetting polymer blends. The blends are made by physical thickening in which a particular crystalline additive is capable of forming a thickened system when it is melt blended with a thermoset resin. The blends are now used commercially in the manufacture of sheet moulding compounds (SMC) where they exhibit important advantages over conventional systems. In previous reports from this laboratory the morphology of these blends was studied[6] and on the basis of secure physical foundations, a model for blend morphology was presented. In this paper the effect of the presence of resin on melting and crystallisation temperature of thickening additive is studied using DSC technique. The corresponding enthalpies of transition are also measured and are compared with values expected from dilution effect. Finally the interaction parameter between resin and additive is calculated from a depression in the melting point of the blend.
[6] Bush S F, Esfandeh M and Methven J M, “New Blend Morphologies for Low Pressure Moulding Compounds”, Polymer Processing Society, 15th International Meeting, Hertogenbosch, The Netherlands, May 31st-June 4th (1999)