This paper investigates the surface treatment effect of ground tire rubber (GTR) on the water absorption and tensile properties of aged GTR/epoxy composites. The GTR was treated using 10 wt-% NaOH solution and 1 wt-% stearic acid (SA) in acetone. The results showed that the GTR addition increased the water absorption and decreased the tensile strength and elastic modulus of epoxy composites. In dry condition, compared to the untreated GTR, the tensile strength of the treated GTR decreased by about 4.8% and 2.9% for the NaOH-and SAtreated GTR, respectively. Nevertheless, the addition of treated GTR increased the elastic modulus of epoxy composites by about 8.4% and 6.0% for the NaOH-and SA-treated GTR, respectively. For the aged epoxy, the tensile strength and elastic modulus decreased further due to the matrix plasticisation and degradation of the interface GTR/epoxy strength. It was found that the SA-treated GTR has better performance than the NaOH-treated GTR.

The present work investigates the effect of surface treatment of ground tire rubber (GTR) waste on the tensile properties of GTR /epoxy composites. The GTR was treated using 10 wt% alkali solution and 1 wt% stearic acid in acetone. It was found that the treated GTR decreased the tensile strength, about 4.8 and 2.9% for NaOH-and stearic acid-treated GTR, respectively, compared to the untreated GTR. Nevertheless, the treated rubber increased the elastic modulus of the epoxy composites, about 5.2 and 9.3% for the NaOH-and stearic acid-treated GTR, respectively, compared to the untreated GTR. The strain at break and the absorbed energy of the treated GTR/epoxy composites were lower than the untreated GTR, consistent with the increase of elastic modulus for the treated GTR. Scanning electron microscopy revealed that the bonding of the stearic acid-treated GTR-matrix was good, indicating better interfacial strength than the untreated and alkali-treated GTR-epoxy matrix.