Preparation of a novel polyurethane network based on PPG–PGN–PPG: investigation of the effect of plasticizers on its properties

Abstract

In this research to improve the thermal and mechanical properties of polyglycidyl nitrate (PGN)-based energetic polyurethane network was used a novel flexible chain triblock copolymer based on polypropylene glycol–poly glycidyl nitrate–polypropylene glycol (PPG–PGN–PPG). Energetic polyurethane was prepared by curing of the triblock copolymer with different curing agents (TDI, IPDI, N100, IPDI/N100) and different NCO/OH ratios. To evaluate the effect of plasticizer on the thermo-mechanical properties of the polyurethane, the compatibility of copolymer with three energetic plasticizers, including n‐butyl nitroxyethyl nitramine (BuNENA), trimethylol ethane trinitrate (TMETN), and 1,2,4-butanetriol trinitrate (BTTN) was studied using the swelling test and thermal analysis. The results indicate that BuNENA is more compatible with this copolymer than other plasticizers. The mechanical properties effect of the BuNENA plasticizer on the polyurethane network was investigated using dynamic mechanical analysis as well as the tensile test. The IPDI/N100 curing agents-polyurethane mixture, demonstrated appropriate mechanical properties (0.35 MPa stress and 70% elongation) that make it a suitable binder system comparison with pure PGN (unstable and de-cured). Also the mechanical properties of the prepared polyurethane containing 15 wt% BuNENA showed 0.17 MPa stress and 98% elongation.