Preparation of a novel P/Si polymer and its synergistic flame retardant application on cotton fabric

Cotton fabrics have been extensively used in our lives, but their flammable properties caused much potential harm. The purpose of our work is to give cotton fabrics certain flame retardant properties. Hence, a novel polymer, poly (oligodimethylsiloxyl spiryclic pentaerythritol bisphosphorate) (PPDMS) was successfully synthesized by a chemical reaction. The structure of product PPDMS was characterized by FTIR, 1 H NMR and 31P NMR. The limited oxygen index (LOI) and vertical burning test were adopted to estimate the flame retardant property, as well as mechanism of gas phase flame retardant was investigated by thermogravimetric analysis coupled with Fourier transform infrared analysis (TG-FTIR). The LOI value reached 29.0 % with a char length of 12.0 cm when the weight gain is maximum. The cone calorimetry test was adopted to assess combustion performance, and the pHRR and THR decreased to 108.2 kW/m2 and 1.7 MJ/m2 for treated cotton fabric. Besides, the surface morphology and elemental composition were also characterized. The morphology of char, TG results and TG-FTIR results proved that PPDMS might play a role in two phases (condensed and gas).