Guar galactomannan

Fig. 11.—Circular Dichroism Spectrum for a Solid Film of Guar Galactomannan. (Redrawn from Ref. 24.)...

The 2-cyanoethyl ethers of varying degrees of substitution of a guar galactomannan were subjected to periodate oxidation.88 The results that were obtained are indicative of a random distribution of the cyano-ethyl grouping. 

Robinson, G., Ross-Murphy, S. B., and Morris, E. R. (1982). Viscosity-molecular weight relationships, intrinsic chain flexibility, and dynamic solution properties of guar galactomannan. Carbohydr. Res. 107 17-32. 

Rayment, R, Ross-Murphy, S. B., and Elhs, P. R. 1998. Rheological properties of guar galactomannan and rice starch mixtures. II. Creep measurements. Carbohydr. Polym. 35 55-63. 

BP Guar galactomannan PhEur Guar galactomannanum USPNF Guar gum... 

Fig. 24.—Schematic Drawing of Possible Chain Structures for Guar Galactomannan. (X-ray data favor the structure on the right." )...

Fig. 25.—Schematic Drawing Illustrating the Probable Packing of Guar Galactomannan...

Changes in unit-cell dimensions of guar galactomannan with relative humidity are highly anisotropic, as is shown by the data in Table III. The water lodges exclusively in planes parallel to the chains and at right angles to the ab sheets, as shown in Fig. 25. 

Unit-cell Size, in A., for Guar Galactomannan at Different Contents of Moisture... 

Beer M. U., Wood P. J., Weisz J. 1999. A simple and rapid method for evaluation of Mark-Houwink-Sakurada constants of linear random coil polysaccharides using molecular weight and intrinsic viscosity determined by high performance size exclusion chromatography Application to guar galactomannan. Carbohvdr. Polymers. 39, 377-380. 

For polymer solutions and melts, it is often claimed that the deformation yniax = K max accumulated before the stress reaches the maximum is independent of the shear rate and takes a value of order unity (1.0 in the literature [40]). In other studies [41,42], it depends on the shear rate, and is approximately described by the formula /max=a b+ Y where a and b are numerical constants of order unity, and r is the relaxation time. In gelling solutions, ymax seems to depend on the system. For aqueous solutions of Guar galactomannan [43] at 3 wt% has ymax — 2, while in aqueous solutions of xanthan polysaccharides [44] at 2 wt% it increases with the shear rate from 0.5 to 1.0. 

Production of Oxidized Guar Galactomannan and Its Applications in the Paper Industry... 

Gebert MS, Friend DR. Purified guar galactomannan as an improved pharmaceutical excipient. Pharm Dev Technol. 3 (3) 315-323,1998. 

Cheng, et al. used FRAP to monitor the diffusion of extremely small probes (1 < < 20 nm) in solutions of guar galactomannan and polyethylene oxide(24). 

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