Flame Retardant Finishing of Cotton Fleece Fabric: Part VI. The Combination of a Hydroxyl-Functional Organophosphorus Oligomer and 1,2,3,4-Butanetetracarboxylic Acid

Abstract

The use of flame retardant finishing becomes necessary for cotton fleece to pass the U.S. government regulation ‘Standard for the Flammability of Clothing Textiles’ (16 CFR 1610). The objective of this research was to reduce the flammability of cotton fleece using a flame retardant finishing system consisting of a hydroxyl-functional organophosphorus oligomer (HFPO) as a flame retardant and 1,2,3,4-butanetetracarboxylic acid (BTCA) as a bonding agent. We investigated the role triethanolamine (TEA) played as a reactive additive in the HFPO/BTCA finishing system on cotton fleece. We also applied micro-scale calorimeter (MCC) to study the effectiveness of HFPO and BTCA in reducing the flammability of cotton. BTCA alone was able to reduce the peak heat release rate (PHRR) of cotton as demonstrated by the MCC data. Combining BTCA with HFPO decreased PHRR further and also significantly reduced the decomposition temperature and the temperature at PHRR of cotton. The cotton fleece treated with HFPO/BTCA/TEA passed the federal regulation (16 CFR Part 1610) and achieved ‘Class 1’ flammability. The treated cotton fleece was durable to multiple home laundering cycles. The use of TEA enhanced the performance of HFPO/BTCA and the treatment caused no significant changes in fabric physical properties.