Synthesis and Characterization of GAP-THF Copolymers

The present investigation describes the synthesis and characterization of poly(glycidyl azide-co-tetrahydrofuran) poly(GA-THF) or GAP-THF copolymers which are recognized as high-energy binders/plasticizers in explosive systems. GAP-THF copolymers were synthesized by copolymerization of epichlorohydrin (ECH) with tetrahydrofuran (THF) in presence of borontrifluoride etherate (BF3-etherate) and ethylene glycol (EG) as catalyst and co-catalyst, respectively; and subsequent azidation of the product with sodium azide in dimethylformamide at 120°C. The GAP-THF copolymers and their precursors PECH-THF copolymers were well characterized by UV, IR, 1H-NMR, 13C-NMR spectroscopy. Molecular weights of these copolymers were determined using VPO (Vapor pressure osmometer) and GPC (Gel permeation chromatography) techniques. The synthesized GAP-THF copolymer followed a thermal decomposition behavior in its DSC and TGA analyses similar to that of pure GAP. However, the copolymer GAP-THF has shown a very low glass transition temperature (Tg) of − 64°C.