A novel DDPSi-FR flame retardant treatment and its effects on the properties of wool fabrics

A novel flame retardant monomer DDPSi-FR containing organophosphorus and silicon was prepared using 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO), 4-hydroxybenzaldehyde (HBA), and 3-glycidoxypropyltrimethoxysilane (GPTMS). The chemical structure of DDPSi-FR was characterized by Fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS). Subsequently, after treating the wool fabrics, the effects of the monomer on the flame retardancy, thermal stability, and mechanical properties were studied. The flame retardant and thermal properties were evaluated by conducting vertical flame tests, limiting oxygen index (LOI) determination, and thermogravimetric analysis (TGA). The results showed that improved flame retardancy and thermal stability were achieved. Notably, the flame retardancy was retained even after 15 washing cycles. The mechanical properties were evaluated using the bursting strength, and the results indicated that DDPSi-FR treatment improved the breaking strength.