COMPARISON OF DIFFERENT REACTIVE ORGANO-PHOSPHORUS FLAME RETARDANT AGENTS FOR COTTON:PART I.THE BONDING OF THE FLAME RETARDANT AGENTS TO COTTON

摘要

N-methylol dimethylphosphonopropionamide (MDPA),known as "Pyrovatex CP" commercially,has been one of the most commonly used durable flame retardant agents for cotton.In our previous research,we developed a flame retardant finishing system for cotton based on a hydroxy-functional organophosphorus oligomer (HFPO).In this research,we investigated the bonding of the two flame retardant finishing agents,e.g.,MDPA and HFPO,to cotton fabrics.We found that MDPA can be bound to cotton by the N-methylol group in its molecule.The presence of trimethylolmelamine (TMM) increases the amount of MDPA bound to cotton.For HFPO,however,the use of a bonding agent,such as TMM and dimethyloldihydroxyethyleneurea (DMDHEU),is necessary for it to be bound to cotton.Both the amount of HFPO bound to cotton and the laundering durability of treated cotton fabric are determined by the effectiveness and concentration of the bonding agent.We also found that the amount of the flame retardant agent bound to cotton is significantly higher for the HFPO system than that for the MDPA system when equal moles of N-methylol group are present in the system.The bonding between MDPA and cotton is significantly more durable to multiple home laundering than that between HFPO and cotton.The higher laundering durability of MDPA on the cotton fabric is attributed to the higher content of N-methylol contained in the MDPA/TMM system.The selection of catalyst also plays a significant role in the bonding of flame retardant agents and cotton.