MECHANICAL PROPERTIES OF VINYL ESTER RESINS

EXEQUIEL S. RODRIGUEZ; ANALÍA VÁZQUEZ

Los Cocos, Córdoba, Argentina

Simposio; III Argentine-Chilean Polymer Symposium; 2005

The most used resins in Resin Transfer Molding (RTM) process are unsaturated polyesters and vinylesters. The last ones have better mechanical properties and especially they have low viscosity for injection at low pressure Mechanical properties of vinyl ester resins change with the formulation and cure temperature due to the building up of the network microstructure. This microstructure is formed by microgels, which are domains of high crosslinking density, connected by linear polystyrene chains. The connected microgels form clusters which lead to the formation of a nodular structure. How variables like styrene content, cure temperature or resin molar mass affect the final microstructure is not well understood. How this microstructure affects the mechanical properties of the cured resin is not clear either. The aim of this work is to characterize some mechanical properties of two commercial vinyl ester resins and relate their behavior with their microstructure.