The morphology and mechanical properties of poly(ethylene terephthalate) (PET)-epoxy blends and the application of these blends in continuous glass fibre reinforced composites have been investigated. Epoxy resin was applied as a reactive solvent for PET to obtain homogeneous solutions with a substantially decreased melt viscosity. The epoxy resin in these solutions was cured using an amine hardener according to two different schedules. In the first, high temperature curing at 260°C preceded low temperature crystallisation of the PET at 180°C. In the second, the PET was allowed to crystallise prior to low temperature curing at 180°C. After cure, all blends revealed a phase separated morphology of dispersed epoxy in a continuous PET matrix. The flexural strength and failure strain of all cured blends showed an increase with increasing epoxy content, whereas the high temperature cured blends exhibited overall lower flexural properties than those cured at the lower temperature. Microstructural analysis and flexural properties of continuous glass fibre reinforced PET-epoxy laminates showed that the composites obtained had a low void content. These PET-epoxy laminates had increased inplane shear strength in comparison with unmodified PET based laminates, indicating considerably increased fibre-matrix adhesion.
Saalbrink, A., Mureau, M., & Peijs, A. A. J. M. (2001). Blends of poly(ethylene terephthalate) and epoxy as matrix material for continuous fibre reinforced composites. Plastics, Rubber and Composites, 30(5), 213-221. https://doi.org/10.1179/146580101101541642