Sol-gel and polyurethane based flame retardant and water repellent coating for Palm/PES nonwovens composite

In this paper, a new commercial and industrial value-added nonwoven textile fabrics based on natural fiber was developed. These nonwovens have been firstly produced using a needling technic by combining palm and polyester fibers in the weight ratio of 75:25 respectively. Then, they were coated with different silica-based solutions to enhance their water repellent and flame retardant features. For this aim, chloropropyltriethoxysilane (CPTS), tetraethylorthosilicate (TEOS), and polyurethane were achieved to nonwoven fabrics via the sol-gel process. The morphological analysis of samples was performed using Scanning Electron Microscopy. FTIR analysis was used to determinate the chemical structure of nonwovens. The mechanical properties of developed nonwoven materials have been studied according to ISO 13934–1 standard. The thermal properties of materials were investigated using thermal gravimetric analysis (TG). The result confirmed that the mechanical properties of Palm/ Polyester nonwovens coated by CPTS or TEOS were improved as well as their thermal stability and flame resistance. The water absorption capacity, the rain test according to ISO 9073–6, the AATCC 22 spray-rating standard, and the contact angle analysis were performed to evaluate the water-repellent properties of untreated and treated nonwovens. We have found that all coated nonwovens with CPTS exhibit good water-repellent properties. Highlights The needle punching nonwoven made from Palm/Polyester blends (75 wt %/25 wt %) was manufactured and functionalized using sol-gel process with CPTS and TEOS precursors by impregnation method. Polyurethane was used for untreated and treated nonwovens with two precursors (CPTS and TEOS). The percentage of polyurethane was set at 5% and the order of treatments has also been studied. The physical, mechanical, morphological, and thermal properties have been comparatively assessed. All simples coated with CPTS have good tensile strength, water repellency, thermal stability, and flame retardancy compared to other materials.