The Study Of Low Formaldehyde And Durable Flame-Retarding System On Cotton

Much formaldehyde will be released when the cotton fabric is finished withflame retardant and crosslink agent, which both contain the reactive group(?)NCH₂OH. As we know, the formaldehyde can not only do harm to the health,but also pollute our living environment, so using low or non-formaldehydefinishing agent is the trend in future.The goal of this topic is to solve the problem of high formaldehyde contentby optimizing flame retardant CFR-201 and crosslink agent melamine resin.Flame retardant MCFR-201 is etherified by ethanol and then free formaldehydeis captured by Urea. Melamine resin is etherified by ethanol too. As a result,the low-formaldehyde flame retardant MCFR-201 and crosslink agent areprepared. The process of preparation is studied and the structure of MCFR-201and MHMM are affirmed by FT-IR. According to the results from trials, flameretardant MCFR-201 and crosslink agent MHMM possesses good stability andthe content of free formaldehyde is less than 1600ppm and 3000ppmrespectively after a long time.The influence of concentrations of flame retardant and crosslink agent, pHvalue of the finishing solution and the temperature and time of curing onflame-retarding effect are studied. The best conditions are obtained, such as,flame retardant 400 g/L, crosslink agent 160 g/L, urea 20 g/L, soft agent 5 g/L,pH≈5, predrying at 90℃for 5 minutes, curing at 160℃for 3 minutes andpicking up 90%. According to the results from trials, the finished fabricpossesses good flame-retarding effect and washing fastness. Freeformaldehyde in the finished fabric is less than 100ppm after soap-washing. However, the breaking and tearing resistance of the fabric reduce largely, andneed further improvement.