Interaction between low-profile agents and glass fiber in polyester-based composites

Scanning electron microscope and differential scanning calorimetry studies were used to study the morphology and thermal properties of cured systems constituted of different unsaturated polyester formulations, two conventional low-shrink additives and one suitably synthetized additive. The aim was to clarify the influence of these low-profile agents on the resulting phase structure and on the thermal behaviour of the systems. Moreover, the influence was investigated of low-profile agents on the fibre/matrix adhesion in composite materials reinforced with glass fibres coated by silane coupling agents.