The Preparation And Application Of Formaldehyde-free Reactive Flame-retardant On Cotton

Recently, with the increasing of consumption on textiles, the fire accidents caused by textile are rising year after year. The cotton fiber is flammable and its limiting oxygen index is only 18, the lowest among common fibers. So it is extremely important to make flame retardant finishing on cotton textile.In my thesis, three structure-similar phosphate oligomer flame retardants with reactive functional group----hydroxyl, are synthesized by different materials. The temperature, time, reactant ratio and catalyst dosage in the reaction are also researched to obtain the optimum reaction conditions. Besides, the structure of three flame retardants----Ⅰ,ⅡandⅢare characterized through IR,1H-NMR and 31P-NMR.Butane tetracarboxylic acid is acted as a crosslinking agent, and sodium hypophosphite catalyst is acted as a catalyst. The cotton fabric are finished in turn by the process of second baptist second pressure, pre-drying and curing. The influence of the amount of flame retardant, crosslinking and catalyst and the temperature and time of curing on the flame-retardant finishing are also researched. And then we get the best finishing process. Flame retardant performances are tested by vertical combustion and the results show that :Ⅱis excellent at B1 level,Ⅰis good at B2 level andⅢhas a less washability. Thermal analysis is tested by thermo gravimetric analyzer. We can come to a conclusion that three stages of cellulose pyrolysis still exist, but the decomposition temperature of fabric after being finished falls significantly and the residue gains. So the flame retardance improves.