Science Research  Academic Press

Enhancement of Flame Retardancy of Cotton Fabrics by Calcium Hypophosphite-Chitosan Solution Compound Silica Sol

Dan Cheng 
Gang Li 
Fei You 
Keywords: Cotton fabric, gel coating, aromatic chars, flame retardancy

Abstract

To enhance the thermal stability and flame retardancy of cotton fabrics, a hybrid sol was prepared by using silica (SiO2) sol, calcium hypophosphite (CaHP) and chitosan (CS), then finished on the surface of cotton fabrics through dipping-baking (drying) method. The results show that the CaHP-CS and SiO2 are successfully attached to the cotton fabric surface. Remarkably, the limiting oxygen index (LOI) value of the CaHP-CS-SiO2@COT was 31.30 % ( the highest of all samples). In the cone calorimetry test (CCT), the study revealed that the CaHP-CS-SiO2@COT has the lowest peak heat release rate (PHPP), fire growth rate (FGR) and CO2/CO. Its flame retardancy is mainly enhanced by the SiO2 (provides a gel coating with dimensional structure to block the transmission of oxygen and heat, CaHP (promotes cotton cellulose to dehydrate and form aromatic chars) and CS (dilute gaseous products and cool down heated areas).