Brief Review on Glycidyl Azide Polymer (GAP) Curing Mechanisms by Isocyanate and Isocyanate-Free Curing Agents

Document Type : compile

Author

Chemical Engineering Departement, Faculty of Engineering, Comprehensive University of Imam Hossein, Tehran, Iran

Abstract

Glycidyl azide polymer (GAP) is one of the most active energetic binders used in high energy composite solid propellants in the future. An energetic insensitive polymeric binder is one of the most important ingredients in energetic composite propellants formulations. The polymeric binders used in composite solid propellants are usually cross linked polyurethane elastomers that provide a binding matrix for solids such as oxidizers and metal fuels with a plasticizer and other additives in small amounts. The energetic properties of the binder are due to the azido groups that decompos under combustion conditions and convert to nitrogen gas. In the present paper, the GAP curing mechanism with isocyanate and isocyanate-free curing agents have been investigated. Studies show that cured samples curing with isocyanate and isocyanate-free curing agents have good tensile strength and elongation but the curing time varies depending on the type of curing agent used. Cured GAP with isocyanate curing agent during storage shows cracking propagation, while GAp < br />sample cured with isocyanate-free curing agent (BPS) yields better curing without any cavities and bubbles during storage.

Keywords


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