Study On The Synthesis And Application Of Flame-retardants For The Treatment Of PET And Cotton Fabrics

Two kinds of flame-retardants, poly(2-hydroxy propylenespirocyclic pentaerythritol bisphosphonate) (PPPBP) and DiethylN,N-diethanolaminomethylphosphate (DNND) were synthesized and applied in flame-retardant treatment for pure PET and cotton fabrics. Their chemical structures were characterized by FT-IR, Nuclear Magnetic Resonance Spectroscopy (NMR) and Mass Spectroscopy (MS). Flammabilities of the treated fabrics were investigated by Limit Oxygen Index (LOI) and Vertical Burning Test.The char-forming tendency and flame-retardant mechanism of PPPBP for PET fabrics wore investigated by thermogravimetric analysis (TGA). X-ray Photoelectron Spectroscopy (XPS), and Scanning electron microscope (SEM), By investigating thermo-oxidative decomposition kinetic, we analyzed the effect of DNND on the decomposition process of cotton fabrics and its effect on flammability of the fabrics.The flammability of PET/Cotton blend fabrics was investigated after the fabrics were treated by PPPBP and DNND simultaneously.Results show that PPPBP and cotton could improve the fire resistance of PET and cotton fabrics to a great extent respectively. When the add-on of PPPBP reaches 11.6%, the LOI of the treated PET fabric increases to 23.6. Besides, PPPBP improves the dripping of PET fabrics during combustion. The char, the decomposition product of PPPBP has outstanding thermal resistance. The char-forming property and the structure of PPPBP have direct relationship with the improved fire resistance of PPPBP treated PET fabrics. LOI of the DNND treated cotton fabric reaches 28. TGAcurves show that DNND lowers the initial decomposition temperature of cotton fabrics. However, at high temperature range, DNND treated fabrics have higher residue rate. Kinetic analysis shows that at low conversion rate, the Ea of untreated fabric is higher than that of the treated. However, at high conversion rate, the Ea of untreated fabric is lower than that of the treated. Flame retardancy of PPPBP and DNND treated PET/Cotton (35/65) blend fabric is improved obviously. The LOI of the treated blend fabric reaches 26.8.