Thermal Degradation Behavior of Thiol-ene Composites Loaded with a Novel Silicone Flame Retardant

Abstract

A novel silicone flame retardant PMDA was synthesized and blended with a commercial thiol-ene (TE) to obtain a flame-retardant TE (FRTE) composite. The cone calorimeter measurement showed the incorporation of PMDA improved the flame retardancy of the TE composite at concentrations of 5 wt%. The thermal stability and degradation mechanism of FRTE in nitrogen was studied by thermogravimetric analysis. The degradation behaviour of TE containing a PMDA flame retardant was found to be changed. The kinetics of thermal degradation was evaluated by Kissinger method and Flynn-Wall-Ozawa method. The results showed that the activation energies of the FRTE degradation were higher than those of neat TE. However, the degradation mechanism of the TE matrix was not changed by the incorporation of flame-retardant PMDA. In this study, the flame-retardant mechanism of PMDA flame-retardant TE polymer was explained by using two kinetic analysis methods.

Keywords: PMDA; flame retardancy; thermal degradation; thiol-ene.

Figure 1

Synthesis of PMDA.

Figure 2

The heat release rate (a) and total heat release (b) curves for TE composites.

Figure 3

Thermal stability of TE composites.

Figure 4

TGA curves of TE (a) and FRTE (b) composites.

Figure 5

DTG curves of TE (a) and FRTE (b) composites.

Figure 6

$$\ln (\frac{\beta }{T_{\max }^2})$$ vs. $$\frac{1}{T_{\max }}$$ curves of TE and FRTE.

Figure 7

The plots of $$\lg (\beta )$$ vs. 1000/T of TE (a) and FRTE (b).