Acids, organic dibasic

Dibasic Acid Esters. Dibasic acid esters (diesters) are prepared by the reaction of a dibasic acid with an alcohol that contains one reactive hydroxyl group (see Esters, organic). The backbone of the stmcture is formed by the acid. The alcohol radicals are joined to the ends of the acid. The physical properties of the final product can be varied by using different alcohols or acids. Compounds that are typically used are adipic, azelaic, and sebacic acids and 2-ethyIhexyl, 3,5,5-trimethyIhexyl, isodecyl, and tridecyl alcohols. 

Phosphoric Acid. This acid is the primary acidulant in cola beverages. Phosphoric acid is stronger than most organic acids and weaker than other mineral acids. The dibasic properties of phosphoric acid provide minor buffering capacity in the beverage. Food-grade phosphoric acid is commercially available in concentrations of 75%, 80%, and 85% and is one of the most economical acidulants. 

Even the earliest reports discuss the use of components such as polymer syrups bearing carboxylic acid functionality as a minor component to improve adhesion [21]. Later, methacrylic acid was specifically added to adhesive compositions to increase the rate of cure [22]. Maleic acid (or dibasic acids capable of cyclic tautomerism) have also been reported to increase both cure rate and bond strength [23]. Maleic acid has also been reported to improve adhesion to polymeric substrates such as Nylon and epoxies [24]. Adducts of 2-hydroxyethyl methacrylate and various anhydrides (such as phthalic) have also been reported as acid-bearing monomers [25]. Organic acids have a specific role in the cure of some blocked organoboranes, as will be discussed later. 

In certain cases the organic dibasic acid is not sufficiently reactive for the purpose of polymerisation, and so it is replaced either with its anhydride or its acid chloride. For example polyamides (nylons) are often prepared by reaction of the acid chloride with the appropriate diamine. In the spectacular laboratory prepatation of nylon 6,6 this is done by interfacial polymerisation. Hexamethylenediamine is dissolved in water and adipyl chloride in a chlorinated solvent such as tetrachloromethane. The two liquids are added to the same beaker where they form two essentially immiscible layers. At the interface, however, there is limited miscibility and nylon 6,6 of good molar mass forms. It can then be continuously removed by pulling out the interface. 

Elforts have been made to characterize the nature and content of individual components that are present in the low-molecular-mass fraction of the total mill effluents, which include the spent chlorination and alkali extraction stage liquors [2,4]. Approximately 456 types of compounds have been detected in the conventional bleach effluents, of which 330 are chlorinated organic compounds [22]. The compounds may be lumped into three main groups, namely, acidic, phenolic, and neutral (Table 2). Acidic compounds are further divided into the five categories of acids fatty, resin, hydroxy, dibasic, and aromatic acids. The most important fatty acids are formic and acetic acids. The dominant resin acids are abietic and dehydroabietic acids. Among the hydroxy acids identified, glyceric acid predominates. Dibasic acids such as oxalic, malonic, succinic, and mafic acids are derived from the lignin and carbohydrate fraction... 

DOT CLASSIFICATION 5.1 Label Oxidizer SAFETY PROFILE Moderately toxic by ingesdon and intraperitoneal routes. A powerful oxidant. Incompadble with Al, As, C, Cu, charcoal, Mn02, metal sulfides, S, dibasic organic acids, organic matter, P. When heated to decomposidon it emits toxic fumes of CT. See also CHLORATES for fire, disaster, and explosion hazards. 

Potassium hydrogen phthalate (KHP) is the mono potassium salt of a weak organic dibasic acid. 

In certain cases the organic dibasic acid is not sufficiently reactive for the purpose of polymerisation, and so it is replaced either with its anhydride or its acid chloride. For example polyamides (nylons) are often prepared by reaction of the acid chloride with the appropriate diamine. In the spectacular... 

Free energies, heats and entropies of ionization of some organic dibasic acids... 

The P-nucleating agent for polypropylene is a water-free admixture of calcium carbonate and a calcium salt of a dibasic organic acid. The dibasic organic acid is selected from the group consisting of pimelic acid, suberic acid, and azelaic acid. The most suitable composition contains calcium carbonate and pimelic acid. The dibasic acid is reacted with calcium compound at temperature of 150°C in fluidized bed reactor. ... 

COPs differ from simple polyester thermoplastics, which are typically hard crystalline polymers of organic dibasic acids and diols. COPs have an excellent combination of properties and are accordingly priced higher than thermoplastic elastic olefins (TEOs) or thermoplastic vulcanizates (TPVs). 

Both soap t5rpes contain the lithium salt of a fatty add. Lithium complex soaps contain an additional lithium salt, or complexing agent, most commonly a dilithium salt of a low molecular weight dibasic organic acid or dibasic ester (13). 

Huyskens PL, Lambeau YO (1978) Ionic conductances and Walden products of anions mono- and dissolvated by citric acid in acetonitrile. J Phys Chem 82 1892-1897 Apelblat A, Neueder R, Barthel J (2006) Electrolyte data collection. Electrolytic conductivities, ionic conductivities and dissociation constants of aqueous solutions of organic dibasic andtribasic acids. Chemistry Data Series, vol XII, Part 4c. Dechema, Frankfurt Lee WH, Wheaton RJ (1978) Conductance of symmetrical, unsymmetrical and mixed electrolytes. Part 2. Hydrodynamic terms and complete conductance equation. J Chem Soc Earaday Trans 74 1456-1482... 

Apelblat A, Neueder R, Barthel J (2006) Electrolyte data collection. Electrolyte conductivities, ionic conductivities and dissociation constants of aqueous solutions of organic dibasic and tribasic acids. Chemistry Data Series vol. XII, Part 4c. Dechema, Frankfurt a. M. 

Polymeric plasticizers are prepared by reacting diols (glycols) with organic dibasic acids, usually in the presence of monobasic acids or alcohols. Normally, the reaction is direct esterification, but other approaches are possible to prepare polymeric plasticizers. The reaction is as follows ... 

Alkyds are formulated from polyester resins, cross-linking monomers, and fillers of mineral or glass. The unsaturated polyester resins used for thermosetting alkyds are the reaction products of polyfunctional organic alcohols (glycols) and dibasic organic acids. 

Environmental Aspects. Airborne particulate matter (187) and aerosol (188) samples from around the world have been found to contain a variety of organic monocarboxyhc and dicarboxyhc acids, including adipic acid. Traces of the acid found ia southern California air were related both to automobile exhaust emission (189) and, iadirecfly, to cyclohexene as a secondary aerosol precursor (via ozonolysis) (190). Dibasic acids (eg, succinic acid) have been found even ia such unlikely sources as the Murchison meteorite (191). PubHc health standards for adipic acid contamination of reservoir waters were evaluated with respect to toxicity, odor, taste, transparency, foam, and other criteria (192). BiodegradabiUty of adipic acid solutions was also evaluated with respect to BOD/theoretical oxygen demand ratio, rate, lag time, and other factors (193). 

Synthetic oils have been classified by ASTM into synthetic hydrocarbons, organic esters, others, and blends. Synthetic oils may contain the following compounds diaLkylben2enes, poly(a-olefins) polyisobutylene, cycloaUphatics, dibasic acid esters, polyol esters, phosphate esters, siUcate esters, polyglycols, polyphenyl ethers, siUcones, chlorofluorocarbon polymers, and perfluoroalkyl polyethers. 

Plasticizers. Plasticizers are materials that soften and flexibilize inherently rigid, and even britde polymers. Organic esters are widely used as plasticizers in polymers (97,98). These esters include the benzoats, phthalates, terephthalates, and trimeUitates, and aUphatic dibasic acid esters. Eor example, triethylene glycol bis(2-ethylbutyrate) [95-08-9] is a plasticizer for poly(vinyl butyral) [63148-65-2] which is used in laminated safety glass (see Vinyl POLYMERS, poly(vinyl acetals)). Di(2-ethyUiexyl)phthalate [117-81-7] (DOP) is a preeminent plasticizer. Variation of acid and/or alcohol component(s) modifies the efficacy of the resultant ester as a plasticizer. In phthalate plasticizers, molecular sizes of the alcohol moiety can be varied from methyl to tridecyl to control permanence, compatibiUty, and efficiency branched (eg, 2-ethylhexyl, isodecyl) for rapid absorption and fusion linear (C6—Cll) for low temperature flexibiUty and low volatility and aromatic (benzyl) for solvating. Terephthalates are recognized for their migration resistance, and trimeUitates for their low volatility in plasticizer appHcations. 

Carbohydrates, polyhydric alcohols, higher organic acids (e.g. stearic), dibasic and hydroxy-acids cg. tartaric), certain amides (yg. oxamide), alkaloids, and azo and other organic colouis char... 

Kost et al. studied the interaction of indole magnesium iodide with a number of cyclic anhydrides of dibasic organic acids.In addition to 254 the following. 3-indolyloxo acids were prepared in this manner -(3-indolyl)-8-oxovaleric acid (274), y-(3-indolyl)-y-oxocrotoiiic acid... 

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