The aim of this work is to study the effects of electron beam irradiation on thermal properties and particle size distribution of magnesium hydroxide. The sample was irradiated by the high-energy electron beam at the different irradiation doses in air at room temperature. The high-energy electron beam was generated by electron accelerator model ILU-6 which is located in BINP SB RAS, Novosibirsk, Russia. The changes of thermal behaviours and particle size distribution of studied sample were analyzed by using thermogravimetric analysis/ differential scanning calorimetry, SR-XRPD and image analysis, respectively.
The TGA and DSC data show that there was no changes occuring in Tmax (the temperature of maximum rate of mass loss) values of the sample before and after irradiation. However, the irradiated sample began to lose mass at the lower initial temperature as compared with this temperature of the sample without irradiation and the quantities of released water of irradiated specimen are higher than these values of non-irradiated one. In addition, DSC profiles indicate that the endothermic effects of irradiated sample are stronger than that of the sample without irradiation. The SR-XRPD results also agrees with the previous TGA and DSC results.
The the median particle size value (d50) of all irradiated samples is lower than d50 of non-irradiated one.
The results of studying of thermal behaviours and particle size distribution of magnesium hydroxide before and after modifying by high-energy electron beam irradiation in this work are possitive and greatly important, especilally in studying polymer composite materials using magnesium hydroxide as a flame retardant. All results indicate that high energy electron beam irradiation significantly improve the flame-retardant properties of studied magnesium hydroxide.
This work was supported by RFBR grant 19-29-12045 and Ministry of Science and Education of Russia grant АААА-А17-117030310280-6.