Mechanical properties of short glass fibre reinforced and functionalized rubber-toughened PET blends

In this study, the effectiveness of short glass fibre (SGF) reinforcements in poly(ethylene terephthalate) (PET) and blends of maleic anhydride grafted styrene-ethylene-butadiene-styrene/PET (MA-g-SEBS/PET) matrices have been investigated. One of the drawbacks for rubber toughening of polymers is the severe reduction in tensile properties (i.e. tensile modulus and tensile strength). With the incorporation of SGF into ternary SGF/rubber/PET blends, the resulting blends may possess attractive tensile and impact characteristics. From this research, it was observed that SGF is effective in improving the tensile modulus, tensile strength and notched impact strength in the SGF/PET binary blends. However, the presence of MA-g-SEBS rubber in the SGF/rubber/PET blends did not improve the notched impact strength, while the tensile properties were adversely affected. Scanning electron microscopy (SEM) examination observed that in the ternary blends, a layer of MA-g-SEBS/PET matrix was coated onto the glass fibres. These coatings reduced the interfacial shear strength between the fibre and matrix, which gave rise to the severe reduction in tensile strength with increasing rubber content.