Polyalcohols, Oxidation

A corrosion inhibitor with excellent film-forming and film-persistency characteristics is produced by first reacting Cig unsaturated fatty acids with maleic anhydride or fumaiic acid to produce the fatty acid Diels-Alder adduct or the fatty acid-ene reaction product [31]. This reaction product is further reacted in a condensation or hydrolyzation reaction with a polyalcohol to form an acid-anhydride ester corrosion inhibitor. The ester may be reacted with amines, metal hydroxides, metal oxides, ammonia, and combinations thereof to neutralize the ester. Surfactants may be added to tailor the inhibitor formulation to meet the specific needs of the user, that is, the corrosion inhibitor may be formulated to produce an oil-soluble, highly water-dispersible corrosion inhibitor or an oil-dispersible, water-soluble corrosion inhibitor. Suitable carrier solvents may be used as needed to disperse the corrosion inhibitor formulation. 

The hydroboration/oxidation sequence does not change the molecular-weight distribution. Gel permeation chromatography (GPC) measurements in dimethyl-formamide (DMF) with the resulting polystyrene-ft-polyalcohol polymers show very similar polydispersity indexes (Table 10.2). Here, the hydroboration/oxidation sequence is clearly superior to the epoxidation reaction, which leads to a... 

If the products of periodate oxidation are reduced with sodium borohy-dride, polyalcohols are produced which may be readily hydrolysed under mildly acidic conditions and the reaction products can be determined. The identification of these products gives considerable information about the linkages between the polysaccharide components and also their sequence in the overall structure. 

Trifluoroacetic acid is volatile, and thus readily removed. This acid was used by Albersheim and coworkers for the hydrolysis of plant cell-walls,39 and has since been employed for cell walls,40-43 plant mucilages,44 blood-group oligosaccharides,45 peptidogalactoman-nans,46 heparin,47 and disaccharides in blood and urine.48,49 It has also been suggested as an alternative to 6 M hydrochloric acid in the determination of amino sugars,50 and for the hydrolysis of polyalcohols produced by periodate oxidation of polysaccharides.503 Lee... 

Further examples of modified Smith degradation, in which the polyalcohol is methylated prior to hydrolysis under mild conditions, uronic acid degradation, and /3-elimination preceded by oxidation have been reported in connection with structural studies on the Klebsiella type 28 (Ref. 182), 57 (Ref. 183), 59 (Ref. 142), and 81 (Ref. 184) capsular polysaccharides. 

Periodate oxidation NaI04 nrnu Hydrolysis of polyalcohol ... 

The simplest carbohydrates, sometimes referred to as monosaccharides, or sugars, are either polyhydroxyaldehydes (aldoses) or polyhydroxyketones (ketoses). They can be derived from polyalcohols (polyols) by oxidation of one carbinol group to a carbonyl group. For example, the simple three-carbon triol, glycerol, can be converted either to the aldotriose, glyceraldehyde, or to the ketotriose, dihydroxyacetone, by loss of two hydrogens (fig. 12.1). 

Bazzi et al. (2003, 2004) reported (Figure 19) the colloidal precipitation from polyalcohol solution to obtain stable colloidal suspensions of luminescent doped rare earth oxide nanocrystals with an average grain... 

Polyesters. Polyesters are polymers obtained by reacting monomeric polycarboxylic acid and polyalcohols. They are practically free of fatty acids (oils) and have a much simpler structure than that of alkyd. Polyester resins do not undergo oxidative polymerization (curing) and have a different curing mechanism than an alkyd. 

The acid hydrolyzate of a periodate-oxidized glycogen of unspecified origin, and of the derived polyalcohol, contained 1 % of D-glucose. Although it was suggested that this arose from (1 —> 2) or (1 —> 3) linkages, the... 

The hydrophilic part of nonionic surfactants usually consists of a few ethylene oxide (-CH2- CH2-O-) units, also derivatives of polyalcohols (e.g. anhydrosorbitol)... 

One of the most intensively studied systems is probably the oxidation of sugars and polyalcohols in aqueous alkaline solutions at electrodes modified with transition metal oxides, typically NiO. Here, oxidation signals at ca. 4-0.6 V vs. AgCl/Ag were obtained in 0.20 M NaOH. 

All carbohydrates (aldoses and ketoses) and polyalcohols produce a large anodic peak response at ca. +0.15 V. The peak for glucose corresponds to a reaction with n approaching 10 equiv/mol for fluid velocities typical of flow-through detection cells. This n value is consistent with an oxidative cleavage for the C1-C2 and Cs-C bonds to form two moles of formate and one mole of dicarboxylate dianion [24]. 

Aluminum oxide Alcohols, alkaloids, amines (strongly basic), tmtioxidants, herbicides, heterocyclics, peptides, polyalcohols, steroids, terpenes, vitamins. 

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