Flame retardant finishing of cotton blend fabrics using an organophosphorus-based system
MetadataShow full item record
In this research, I discovered that both dimethyloldihydroxyethyleneurea (DMDHEU) and trimethylolmelamine (TMM) are able to covalently bond hydroxy-functional organophosphorus oligomer (HFPO) to nylon by the formation of a crosslinked polymeric network. Nylon treated with HFPO/DMDHEU shows higher phosphorus retention and significantly lower stiffness than that treated with HFPO/TMM. The bonding of HFPO to cotton using DMDHEU as a bonding agent was also studied. The laundering durability of HFPO bound to cotton through DMDHEU is attributed to the formation of a crosslinked polymeric network of HFPO/DMDHEU/cotton cellulose, which also increases the fabric stiffness. Even though both TMM and DMDHEU are able to covalently bond HFPO to nylon/cotton blend fabric, DMDHEU is more effective for bonding HFPO to the nylon/cotton blend fabric than TMM. The nylon/cotton fabric treated with HFPO/DMDHEU shows higher flame retardant performance and lower stiffness than that treated with HFPO/TMM after multiple launderings. The nylon/cotton blend fabric treated with HFPO/DMDHEU shows high levels of flame retardant performance and passes the vertical flammability test even after 50 laundering cycles. HFPO may function through the condensed phase mechanism in the both individual fibers and their blend. In addition, I also discovered that DMDHEU can covalently bond HFPO to polyester and acetate, which creates a new way to durable flame retardant finishing of other cotton blends including cotton/polyester and cotton/acetate blends. The advantages of the above finishing system include: single flame retardant effective for both individual fibers in the blends; high level of flame retardant performance and good laundering durability; easy application; limited effects on the physical properties of the treated fabric; and low cost. I also developed a non-formaldehyde flame retardant finishing system based on HFPO for the Nomex/cotton blend fabric using 1,2,3,4-butanetetracarboxylic acid (BTCA) as a bonding agent and triethanolamine (TEA) as a co-reactant. The main functions of TEA are to improve the hydrolysis-resistance of the HFPO bound to the Nomex/cotton blend and also enhance the flame retardant performance of HFPO through the phosphorus-nitrogen synergism. The Nomex/cotton blend fabric treated with the HFPO/BTCA/TEA system shows high levels of flame retardant performance at relatively low add-on levels.