Cross-linked guar gum

The first and still successful dense slurry was sensitised with TNT and therefore consisted of a suspension of TNT and solid ammonium nitrate in a solution of ammonium and sodium nitrates gelled with cross-linked guar gum. The TNT is preferably in the form of small pellets. No further fuel than the TNT is essential but aluminium can be added for increased... 

Chaurasia, M., Chourasi, M. K., Jain, N. K., Jain, A., Soni, V, Gupta, Y., and Jain, S. K. Cross-linked guar gum microspheres A viable approach for improved delivery of anticancer drugs for the treatment of colorectal cancer. AAPS PharmSciTech, 7(3), Article 74 (2006). 

S.R. Kumar, T. Piyush, R. Suman, and T. Akanksha, Preparation and characterization of cross-linked guar gum microspheres Optimization using factorial design, Chem. Pharm. Bull. (Tokyo), 59 (2), 185, 2011. 

A. Das, S. Wadhwa, and A. Srivastava, Cross-linked guar gum hydrogel discs for colon-specific delivery of ibuprofen Formulation and in vitro evaluation. Drug Delivery, 13 (2),... 

J.K. Sarmah, R. Mahanta, S.K. Bhattacharjee, R. Mahanta, and A. Biswas, Controlled release of tamoxifen citrate encapsulated in cross-linked guar gum nanoparticles, Int. J. Biol. Macromol, 49 (3), 390-396,2011. 

FIGURE 17.8 Effect of pH and temperature on the viscosity of borate cross-linked guar gum gels (30 lb/ Mgal). (Adapted from Harris, P C Journal of Petroleum Technology, pp. 264-269, March 1993 (SPE 24339). Copyright 1993 by SPE.)... 

Cross-Linking of Polyols. Polyols such as natural polysaccharides, eg, cellulose, starch, guar gum and their derivatives, and polyvinyl alcohol and its derivatives can be cross-linked by organic titanates. 

Polymer chains of guar gum and its derivatives, in fact of all galactomannans, are readily cross-linked with borate and titanium ions. Gels formed in this way are mbbery in nature. 

Hexamine serves as a parent compound for the preparation of RDX, HMX Hexamethyl-enetriperoxidediamine. It is also used in a mixture with sodium phenate, as an adsorbent of phosgene in gas masks. Its use as a cross-linking agent for guar gum in AN-slurry explosives has been patented (Refs 9 10)... 

AN with sufficient water to give such viscosity that the particulate material remains in suspension and hence in uniform distribution thruout the slurry. The viscosity may be improved by adding thickeners such as guar gum, polyacrylamides, etc, with or without cross-linking agents. Up to 50% NC may be replaced with TNT, Tetryl, PETN, RDX or HMX up to 25% AN may be replaced with alkali metal nitrates, such as NaNOg)... 

AN Blasting Explosive consisting of an HE (such as TNT or RDX), satd aq AN guar gum with its cross-linking agent borax. Part of AN can be replaced by NaNOg]... 

H.R.Fee R.W. Lawrence, LTSP 3318740 (1967) CA 67, 55844s (1967) [An aqueous slurry-type blasting agent is provided by a mixt of 12—20% water, 1-118 (preferably 5-14%) sensitizer such as hexamethylenetetramine mononitrate (I), dinitrate or a mixt of the two, 45-65% AN, 5-20% NaNOa and 0.2-5.0 (preferably 0.5—2.0%) guar-gum thickener in cross-linked form. A supplemental sensitizer such as fine Al, Mg AI or C (or hydrocarbon oil) may be used, especially if less than 5% of... 

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