Recent work by Barker, et al. (1) indicated that a high yield of nondialyzable material (i.e., material retained by a dialysis membrane) could be obtained by -irradiating deaerated aqueous solutions of glucose with gamma-rays from a cobalt-60 source. As a result of several chemical tests conducted on the material, they suggested that the nondialyzable material was a polymer of gluconic acid linked together by carbon-carbon bonds. No indication of the size and shape of the molecules was given.In this thesis, 1.0% aqueous glucose solutions were irradiated with high energy electrons. The yield of polymer, measured as either nondialyzable material or ethanol precipitate, increased with both the dose and the dose rate. This would be expected in view of Barker's proposed mechanism which involves hydrogen abstraction from the sugar molecules followed by coupling of the resulting sugar free radicals.Increasing the dose rate would be expected to increase the concentration of hydrogen and hydroxyl free radicals, which in turn would increase the concentration of sugar free radicals and thus increase the liklihood of radical coupling.The weight average molecular weights of the whole polymers isolated by ethanol precipitation were measured by light scattering in water solution. The molecular weights ranged from 9800 to 5,000,000, and hence are much larger than previously imagined. Measurement of the number average molecular weight of one of the polymers by osmometry established an M/Mn ratio of 4.9, thus indicating a broad distribution of molecular weights within the polymer.The polymers exhibited intrinsic viscosities in the range of 0.02 to 0.26 dl./g. in water at 30.000 + 0.005°C., and are therefore thought to be very highly branched.Although no molecular weights were obtained, the authors assumed the material was polymeric, and devoted most of their work to a chemical characterization of the material. The work on the polymer formed by the 7.10 megarad (Mrad) treatment of glucose is of particular interest to this thesis, and may be summarized as follows:a. The material was acidic, having an equivalent weight of 328, or a carboxyl content of 13.7%.b. The polymer had an aldehyde content of 16.0%, as measured by alkaline hypoiodite.c. The polymer was resistant to acid hydrolysis.In fact, most of the polymer precipitated in hot acid. The precipitate had an infrared absorption spectrum similar to that of the original polymer, and the soluble portion showed no mobile components with paper chromatography.d. The polymer contained 51.91% carbon and 5.07% hydrogen.e. The polymer exhibited absorption at approximately 265 mu in the ultraviolet.f. The polymer reacted with sodium metaperiodate; about one-third of the material remained nondialyzable.From the above information, the authors concluded that the polymeric linkage was neither that of a glycoside nor an ester. Instead, they proposed a carboncarbon linkage similar to that formed upon irradiation of alcohols (2, .3).The proposed mechanism involved the production of H. and .OH ra...

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