Moisture Resistance, Thermal Stability and Fire Behavior of Unsaturated Polyester Resin Modified with L-histidinium Dihydrogen Phosphate-Phosphoric Acid.


Sałasińska K(1), Celiński M(1), Mizera K(1)(2), Barczewski M(3), Kozikowski P(1), Leszczyński MK(4)(5), Domańska A(6).
Author information:
(1)Central Institute for Labour Protection-National Research Institute, Department of Chemical, Biological and Aerosol Hazards, 00-701 Warsaw, Poland.
(2)Faculty of Materials Science and Engineering, Warsaw University of Technology, 02-507 Warsaw, Poland.
(3)Institute of Materials Technology, Poznan University of Technology, 61-138 Poznań, Poland.
(4)Faculty of Chemistry, Warsaw University of Technology, 02-507 Warsaw, Poland.
(5)Institute of Physical Chemistry, Polish Academy of Sciences, 01-224 Warsaw, Poland.
(6)Łukasiewicz Research Network-Institute for Engineering of Polymer Materials and Dyes, 87-100 Toruń, Poland.


In this paper, the fire behavior of unsaturated polyester resin (UP) modified with L-histidinium dihydrogen phosphate-phosphoric acid (LHP), being a novel intumescent fire retardant (IFR), was investigated. Thermal and thermomechanical properties of the UP with different amounts of LHP (from 10 to 30 wt. %) were determined by thermogravimetric analysis (TG) as well as dynamic mechanical thermal analysis (DMTA). Reaction to small flames was studied by horizontal burning (HB) test, while fire behavior and smoke emission were investigated with the cone calorimeter (CC) and smoke density chamber. Further, the analysis of volatile products was conducted (TGA/FT-IR). It was observed that the addition of LHP resulted in the formation of carbonaceous char inhibiting the thermal decomposition, burning rate and smoke emission. The most promising results were obtained for the UP containing 30 wt. % of LHP, for which the highest reduction in maximum values of heat release rate (200 kW/m2) and total smoke release (3535 m2/m2) compared to unmodified polymer (792 kW/m2 and 6895 m2/m2) were recorded. However, some important disadvantage with respect to water resistance was observed.