Durability of non-woven geotextiles produced from recycled polyethylene terephthalate (PET)

Achieving the goals of sustainable development and circular economy requires recycling and reusing plastic materials. In this research, the durability of five needle-punched nonwoven geotextiles were experimentally studied. The geotextiles were made of recycled PET (rPET), virgin PET (vPET), and combinations of rPET and vPET fibers. The samples were hydrolyzed for a period of 14, 28, and 56 days and the retained tensile strength and puncture resistance of the samples were determined at the end of each interval. Moreover, this study took the benefits from the capability of differential scanning calorimetry (DSC), Fourier transforms in infrared spectroscopy (FTIR) analysis, and scanning electron microscopy (SEM) images to interpret the results acquired. Testing on as-received products, it was understood that the recycling process could increase crystallinity of the fibers, increasing the fibers’ fragility, reducing the tensile strength and elongation capacity of rPET fibers. Moreover, considering the borderline value of 50% retained strength, a shorter service life (up to 30%) of rPET products in comparison with vPET products, due to higher degradation rates, was observed.