Mechanical Properties of PETG Fibres and Their Usage in Carbon Fibres/Epoxy Composite Laminates

Abstract

This paper reports on a melt-spinning process of glycol-modified poly(ethylene terephthalate) PETG and regranulate of PETG. The effect of the processing temperature and winding reel velocity on the diameters of fibres was examined. It was observed with a scanning electron microscope that the surface of fibres produced from recycled PETG are thicker but smoother than fibres made of fresh PETG. Applying a higher drawing velocity helped to decrease the diameters, which were between 75-150 μm. Under static deformation, fibres showed different behaviour, with higher flexibility and lower strength observed for fibres made of PETG regranulate. Both types of fibre were chopped and added to carbon fibre reinforced polymers as interlayers to investigate their effect on mechanical properties. It was found that the flexural strength decreased in the presence of PETG fibres, while interlaminar shear strength improved, but only in the case of fresh PETG fibres.