Chen XL, Hu Y, Song L, Xing WY (2008b) Combustion and thermal behavior of polyurethane acrylate modified with a phosphorus monomer. Journal of Fire Sciences 26(2), 93-108. [In English]

Web link: http://dx.doi.org/10.1177/0734904107083863

Keywords:

flame retardant; UV curable; polyurethane acrylate; combustion; flame-retardant oligomer; acryloxyethyl phosphate); carbon nanotubes; coatings; polypropylene; degradation; mechanism; polymers; modes

Abstract: A series of UV curable flame retardant resins were obtained by blending bis(2-acryloxyethyl) 2.6.7-trioxa-1-phosphabicyclo[2.2.2.]octane4-methylol-1-oxide phosphate (MDMPE) in certain ratios with a commercial polyurethane acrylate (PUA). It has been found that the cured film shows good flame retardancy when the MDMPE is at 30% additive level. The cone calorimeter results show that the heat release rate decreases in comparison with the pure PUA. The thermogravimetric analysis (TGA) and real time Fourier-transform infrared spectroscopy measurements (RTFTIR) results show that the phosphate group in MDMPE first degrades to form poly(phosphoric acid) before the degradation of PUA. Then, the formed poly(phosphoric acid) effectively promotes the conversion of PUA to form char, which prevents the sample from further burning. It can be concluded that MDMPE could catalyze the degradation of PUA to form char residue, and could be used as a UV curable flame retardant which acts by a condensed phase mechanism.