The phosphorus-containing acrylate monomer, 2-acryloyloxyethyl diethyl phosphate (ADEP), was synthesized and applied to cotton fabric by using admicellar polymerization. Sodium dodecylbenzene sulfonate was used as the anionic surfactant. The film of polymerized monomer (PADEP) formed on the cotton surface was characterized by FTIR-ATR spectroscopy and SEM. Thermal and flame retardant properties of PADEP-coated cotton were investigated by TGA and flammability tests. Results showed that PADEP polymer film was successfully formed on the cotton fabric. The TGA and DTG analyses showed that the phosphorus-containing PADEP lowered the decomposition temperature of the treated fabric resulting in a higher char yield than in the case of untreated cotton. The flammability tests showed that the treated cotton had much improved flame retardancy property after the treatment. The treated fabric also retained its good pliability and soft touch with good air permeability. (C) 2008 Wiley Periodicals, Inc.