Epoxy inert binder

There are a number of inert binders such as polyester, epoxy, polysulfide, polyurethane which have been reported as binders for composite propellants and plastic bonded explosives (PBXs). At present, hydroxy-terminated polybutadiene (HTPB) is regarded as the state-of-the-art workhorse binder for such applications. However, the recent trend is to use energetic binders such as poly [3,3-bis(azidomethyl oxetane)] [poly(BAMO)], poly (3-azidomethyl-3-methyl oxetane) [poly(AMMO)], PNP, GAP diol and triol, nitrated HTPB(NHTPB), poly(NiMMO), poly(GlyN) and nitrated cyclodextrin polymers poly(CDN) for PBXs and composite propellants in order to get better performance. 

The inhibition of composite propellants is somewhat easier than that of DB propellants. The binders used for composite propellants (with or without fillers) have been reported for inhibition of composite propellants. Such inhibition systems possess stronger bonds with composite propellants and prove to be more compatible coupled with better shelf-life of the inhibited propellants. However, epoxy or novolac epoxy resin with or without inert fillers is generally preferred for the inhibition of composite propellants due to a combination of properties possessed by them. The inhibition is usually done by casting technique and inhibition thickness is usually required on higher side in order to make the missions successful. In India, thread winding technique or inhibitor sleeve technique is preferred where 2.5-3.0mm inhibition thickness is sufficient as against 3.5-4.0 mm in case of inhibition by casting technique . 

Despite their name, epoxy esters are not really epoxies. Applanan, in fact, writes that epoxy esters are best described as an epoxy-modified alkyd [20]. They are made by nfixing an epoxy resin with either an oil (drying or vegetable) or a drying oil acid. The epoxy resin does not crosslink in the manner of conventional epoxies. Instead, the resin and oil or drying oil acid are subjected to high tanperature, 240°C to 260°C and an inert atmosphere to induce an esterification reaction. The result is a binder that cures by oxidation and can therefore be formulated into one-component paints. 

The chemical inertness of MIO means that it can be used in a variety of binders alkyd, chlorinated rubber, styrene-acrylic and vinyl copolymers, epoxy, and polyurethane [40]. 

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