Reactive Plasticizers Covalently Linked to Glycidyl Azide Polymer via Catalyst‐Free Huisgen Azide‐Alkyne Cycloaddition

Abstract

Reactive plasticizers (RPs) used in glycidyl azide polymer (GAP) were studied. These compounds consisted of an activated terminal alkyne group expected to give rise to Huisgen azide‐alkyne 1,3‐dipolar cycloaddition, which couldprevent the migration of plasticizers. FTIR, 13C and 1H NMR analyses were implemented to confirm that the connection was made properly. The properties GAP/RPs were investigated by DSC analyses, a viscometer, and heat of combustion. The RPs could effectively reduce the viscosity of the GAP from 5.5 Pa.s to 2.5 and 3.8 Pa.s when 40 % (w/w) of the reactive plasticizers are respectively added. Also, the glass transition temperature of GAP reduced from (−38) °C to −41 and −47.7 °C. The heats of combustion were measured by a calorimetric method. A significant difference in the heats of combustion was observed between the reactive plasticizers and reactive energetic plasticizers (from 17.31 kJ/g to 21.42 kJ/g).

Glycidyl Azide Polymer and its Derivatives-Versatile Binders for Explosives and Pyrotechnics: Tutorial Review of Recent Progress

“…The same group also studied the reaction of GAP with other energetic plasticizers, bis-(2-ethylhexyl)-but-2-ynedioate (BEHB) and bis(2-nitropropyl)-but-2-ynedioate (BNPB) [65]. Covalently linked reactive plasticizers BEHB and BNPB effectively reduced the viscosity of GAP from 5.5 Pa•s to 2.5 and 1.5 Pa•s.…”

Synthesis of 1‐Methyl‐4‐methoxyethyl‐1,2,4‐triazolium Dicyanamide and Its Plasticizing Behavior on HTPB/TDI Curing System**

“…In recent years, the development of new low‐vulnerability propellants has put forward higher requirements for the performance of binders [5] . Polymer binders are usually composed of a prepolymer, curing agent, plasticizer, etc., in which the prepolymer reacts with the curing agent to form a crosslinking network to encapsulate the energetic components, [6] and the plasticizer embedded in the crosslinking network plays a key role in regulating mechanical and process properties [7] . Therefore, the plasticizer is a key component for low vulnerability control of propellants.…”

Inserting urethane into 1,2,3‐triazole click‐cured solid propellant binder to form microphase separation and enhance mechanical and combustible performances

“…17,18 The GAP binder system can further form a triazole-based network via alkyne-azide Huisgen cycloaddition, 19,20 which is insensitive to humidity, simpler, and faster than the traditional isocyanates curing system. [21][22][23] However, the practical application of a triazole-cured binder system is inhibited by unsatisfied mechanical properties. 24,25 Unlike the isocyanates curing system, the rigid triazole rings failed to induce the aggregation of hard segments to form a micro-phase separation structure, 26 due to insufficient intermolecular force.…”