Flameproofing modification of synthetic materials by laser radiation

A method of giving flameproof properties to materials and articles in light industry by modification with phosphorus-containing flame retardants under the effect of the energy from CO2 laser radiation was developed. The optimum modification parameters (LR power density of 5.3 W/cm2, treatment time of 30 sec, concentration of flame retardant (FR) in 5–10% solution, impregnation time of 100–120 sec), which allow obtaining flameproof materials with high performance properties were determined. The oxygen index of the cloth increased to 29.5–42%, the breaking strength increased by 8.5–21%, and the abrasion resistance increased by 5–12% without worsening the hygroscopicity and air permeability. The activating effect of laser radiation on the modification process was demonstrated; it resulted in an increase in the sorption capacity of the fibre structure of the materials, diffusion of FR into the bulk of the fibres, uniform distribution of the fibres in the form of finely disperse particles, intensification of the reaction of the components, ordering of the structure, and improvement in the physicomechanical properties of materials and articles in light industry. The method saves on expensive raw materials — flame retardants — due to conducting the modification from low-concentration solutions and allows expanding the line of flameproof materials.