Synthesis and Characterization of Poly(glycidyl nitrate-block-caprolactone-block-glycidyl nitrate) (PGN-PCL-PGN) Tri-Block Copolymer as a Novel Energetic Binder

Abstract

An energetic binder was synthesized through ring opening copolymerization of glycidyl nitrate (GLYN) with polycaprolactone (PCL) as a macroinitiator to form tri‐block copolymer PGN‐PCL‐PGN. Effect of monomer concentration, catalyst, reaction time and solvent was investigated in polymerization. Resulting tri‐block copolymer was characterized by Fourier transform infrared spectroscopy (FT‐IR), nuclear magnetic resonance spectroscopy (NMR), gel permeation chromatography (GPC), differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA). The DSC result shows that glass transition temperature of tri‐block copolymer (Tg=−56.2 °C) is lower than PGN (Tg=−35 °C). In optimal condition, the Mw of this polymer was obtained 2900 g/mol.

Thermal and Rheological Properties of PGN, PNIMMO and P(GN/NIMMO) Synthesized via Mesylate Precursors

“…The molecular structures of PGN, PNIMMO and P(GN/NIMMO) were confirmed by 1 H NMR and shown in Figure 2. In the 1 H NMR spectra of PGN, the signals at approximately 3.36-4.06 ppm were ascribed to the methylene and methine protons, and the peaks at about 4.37-4.64 ppm belong to the methylene 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 protons of the ÀCH 2 ONO 2 [6,16]. In the 1 H NMR spectra of PNIMMO, the single peak at 1.00 corresponded to the methyl protons, the multi-peaks at about 3.23-3.30 ppm were ascribed to the methylene protons, and the peaks at about 4.39 ppm belong to the methylene protons of the -CH 2 ONO 2 [3,17].…”

Combustion Properties of Composite Propellants Based on Two Kinds of Polyether Binders and Different Oxidizers

“…Generally, it can be divided into two categories. The one kind contains azide, such as glycidyl azide polymer , 3,3‐bis(azidomethyl)oxetan ; the other kind contains nitrate, such as nitrated HTPB , polyNIMMO and polyGLYN .…”

Study on the Curing System of Polytriazole Adhesive for Composite Solid Propellant

“…Furthermore, polytriazole adhesive has good compatibility and interface binding force with polar plasticizers or oxidants due to its polarity. In addition, the combustion of triazole structure produces nitrogen and generates a lot of energy to improve the balance of energy and oxygen [14][15][16]. Qu's team [17] reported that polytriazole elastomers prepared from polymer with terminal alkynyl groups cured by azide compounds showed a high performance of mechanical properties including tensile strength of 0.76 MPa and elongation at break of 120 %.…”