(217bf) Vinyl Ester Resin: Rheological Behaviors, Curing Kinetics, Thermo-Mechanical and Tensile Properties

Vinyl ester resins (VERs) at different isothermal temperatures were prepared by isothermally curing for 4 h followed by postcuring at 85 °C for 0.5 h. The effects of isothermal temperature and postcuring process on the curing extent were studied. The curing extent of VERs with different isothermal temperature was studied with the residue heat of cured VERs obtained by differential scanning calorimeter (DSC) tests. And the dynamic rheological behaviors of the uncured samples (liquid phase), including shear storage and loss modulii were investigated. The effects of isothermal temperature on the gel time and the gel temperature were systematically studied as well. The gel time with isothermal and non-isothermal condition was studied by investigating the cross point of shear storage and loss modulii of the resins, and the apparent activation energy is calculated based on the relation between the gel time and the isothermal temperature. And for all the cured samples (solid phase), the mechanical properties including storage and loss modulii, glass transition temperature, tensile strength and Young’s modulus were evaluated together with the curing extent of the VERs.