A novel polydimethylsiloxane comb-shaped copolymer containing P–N elements toward cotton fabrics: flame retardancy and antibacterial property

A novel comb-shaped polydimethylsiloxane derivative (DSCFT) was synthesized to endow the flame retardancy and antibacterial properties of cotton fabrics. The main functional group of DSCFT were tested by Fourier-transform infrared spectroscopy. The vertical combustion test and limiting oxygen index (LOI) were used to measure the flame retardancy of the samples. The cotton samples treated with 300 g/L DSCFT acquired LOI value of 28.2% without the after-flame and after-glow. The DSCFT successfully reacted with the cotton fabrics via the process of treatment were shown by scanning electron microscopy and energy dispersive spectrometer observation. Cone calorimetry and thermogravimetric test were used to evaluate the combustion behavior and thermal stability of treated cotton fabrics. The effective heat combustion and total heat release of treated sample were significantly reduced in comparison with blank fabrics, and 42.74% of the char residue was retained at 800 °C. In addition, the antibacterial radios of treated cotton specimens against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) were 96.8%, and 97.1% in contrast to untreated samples. The tensile strength of cotton fabrics reduced within acceptable range. Thus DSCFT-treated cotton fabrics had the multiple functions of flame retardancy and antibacterial.