Studies on the effect of a covalently bonded PGN based reactive plasticizer on the thermal decomposition behaviour of glycidyl azide polymer

Abstract

Plasticizers are one of the additives that are added to polymers to increase the plasticity or decrease the viscosity of the material. Here, we have synthesized and characterized a new PGN-based reactive energetic plasticizer that has an oligomeric structure. The reactive energetic plasticizer can be grafted onto glycidyl azide polymer via a Cu-free Huisgen azide-alkyne 1,3-dipolar cycloaddition. The effect of the covalently bonded PGN-based plasticizer on the thermal properties of GAP-g-PGN copolymer has been investigated through thermogravimetric analysis and differential scanning calorimetry. The results indicate that the glass transition temperature of the prepolymer is decreased from -47.8 to -50.7 °C. Also, the kinetics of the thermal behaviour of GAP-g-PGN copolymer was determined by the application of the Kissinger and FWO kinetic models. The activation energies calculated by the Kissinger method were 165 and 188 kJ/mol for peak 1 and peak 2, respectively. Furthermore, the critical temperature (Tb) of thermal explosion for this energetic copolymer was estimated to be 182 °C.