Synthesis and characterization of novel energetic plasticizers based on poly glycidyl nitrate

Abstract

ABSTRACT Energetic plasticizers are used in propellants to increase the energy content and improve the glass transition temperature and mechanical properties. The compatibility between polymer and plasticizer is an important criterion for obtaining the best thermomechanical properties. In this research, novel energetic plasticizers were synthesized via end-group modification of poly glycidyl nitrate. Firstly, low molecular weight poly glycidyl nitrate (PGN) (Mn = 523 g.mol−1) and dinitropropyl poly glycidyl nitrate (DNPPGN) (Mn = 1700 g.mol−1) were synthesized by ring-opening polymerization of glycidyl nitrate with 1,4-butanediol and 2,2-dinitro-1,3-propanediol as initiators, respectively, and in the presence of boron trifluoride etherate (BF3.OEt2) as the catalyst. Tetra nitro poly glycidyl nitrate (TNPGN) was synthesized through end-group modification of DNPPGN and also azide-terminated GAP (GAPA) synthesized via modification of PGN as novel energetic plasticizers. The chemical structure of plasticizers was characterized by Fourier transform infrared spectroscopy (FT-IR) and nuclear magnetic resonance spectroscopy (NMR). Thermal behaviors were investigated by differential scanning calorimeter (DSC). The thermal analysis of plasticizers indicated Tg of TNPGN is lower than PGN and other synthesized plasticizers. Also, decomposition temperature (thermal stability) of TNPGN (251°C) is higher than PGN (209°C). Therefore, TNPGN has potential as a novel energetic plasticizer for propellant.