Polycarboxylic acid

5 Carboxylic Acids and Derivative Collectors 2.5.1 Polycarboxylic Acids 

Polycarboxylic acids such as oxalic acid, dihydroxysuccinic acid, and citric acid have been used as depressant. It was reported that polycarboxylic acid collectors for cassiterite can be given as follows [9]  

The molecular weights and the CMC of the above polycarboxylic acids are given as follows  

The flotation results of cassiterite, quartz, and tourmaline using the above polycarboxylic acids are listed in Table 2.6. 

In addition, some polycarboxylic acids are reported in East Germany and Britain. For example, one of the general expressions of polycarboxylic acids is as follows  

Depending upon the number of carboxyl groups, acids can be classified as monocarboxylic acids or polycarboxylic acids. 

Acids which contain only one carboxyl group are called monocarboxylic acids. H—COOH CH3 —COOH C2H5 —COOH 

The general formula of monocarboxylic acids is CnH2n+lCOOH or CnH2n02. Here, n can be any integer. 

Acids which contain more than one carboxyl group are called polycarboxylic acids. If two carboxyl groups are present, the acid is a dicarboxylic acid and if there are three carboxyl groups the acid is a tricarboxylic acid. 

The general formula of a dicarboxylic acid is CnH2n(COOH)2 and general formula of a tricarboxylic acid is CnH2n l (COOH)3. 

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Acid Anhydrides. Symmetrical anhydrides of monocarboxylic acids, when unsubstituted, are named by replacing the word acid by anhydride. Anhydrides of substituted monocarboxylic acids, if symmetrically substituted, are named by prefixing bis- to the name of the acid and replacing the word acid by anhydride. Mixed anhydrides are named by giving in alphabetical order the first part of the names of the two acids followed by the word anhydride, e.g., acetic propionic anhydride or acetic propanoic anhydride. Cyclic anhydrides of polycarboxylic acids, although possessing a... 

Physical properties for naphthalene mono-, di-, tri-, and tetracarboxyhc acids are summari2ed in Table 9. Most of the naphthalene di- or polycarboxyLic acids have been made by simple routes such as the oxidation of the appropriate dior polymethylnaphthalenes, or by complex routes, eg, the Sandmeyer reaction of the selected antinonaphthalenesulfonic acid, to give a cyanonaphthalenesulfonic acid followed by fusion of the latter with an alkah cyanide, with simultaneous or subsequent hydrolysis of the nitrile groups. 

Cobalt in Catalysis. Over 40% of the cobalt in nonmetaUic appHcations is used in catalysis. About 80% of those catalysts are employed in three areas (/) hydrotreating/desulfurization in combination with molybdenum for the oil and gas industry (see Sulfurremoval and recovery) (2) homogeneous catalysts used in the production of terphthaUc acid or dimethylterphthalate (see Phthalic acid and otherbenzene polycarboxylic acids) and (i) the high pressure oxo process for the production of aldehydes (qv) and alcohols (see Alcohols, higher aliphatic Alcohols, polyhydric). There are also several smaller scale uses of cobalt as oxidation and polymerization catalysts (44—46). 

The diacids are characterized by two carboxyHc acid groups attached to a linear or branched hydrocarbon chain. AUphatic, linear dicarboxyhc acids of the general formula HOOC(CH2) COOH, and branched dicarboxyhc acids are the subject of this article. The more common aUphatic diacids (oxaUc, malonic, succinic, and adipic) as weU as the common unsaturated diacids (maleic acid, fumaric acid), the dimer acids (qv), and the aromatic diacids (phthaUc acids) are not discussed here (see Adipic acid Maleic anhydride, maleic acid, and fumaric acid Malonic acid and derivatives Oxalic acid Phthalic acid and OTHERBENZENE-POLYCARBOXYLIC ACIDS SucciNic ACID AND SUCCINIC ANHYDRIDE). The bihinctionahty of the diacids makes them versatile materials, ideally suited for a variety of condensation polymerization reactions. Several diacids are commercially important chemicals that are produced in multimillion kg quantities and find appHcation in a myriad of uses. 

Practically all pyridazine-carboxylic and -polycarboxylic acids undergo decarboxylation when heated above 200 °C. As the corresponding products are usually isolated in high yields, decarboxylation is frequently used as the best synthetic route for many pyridazine and pyridazinone derivatives. For example, pyridazine-3-carboxylic acid eliminates carbon dioxide when heated at reduced pressure to give pyridazine in almost quantitative yield, but pyridazine is obtained in poor yield from pyridazine-4-carboxylic acid. Decarboxylation is usually carried out in acid solution, or by heating dry silver salts, while organic bases such as aniline, dimethylaniline and quinoline are used as catalysts for monodecarboxylation of pyridazine-4,5-dicarboxylic acids. 

Similar to tannins, the polycarboxylic acid group provides a chelating function that ties up metal ions. The anionic sulfonate group functionality confers both solubility and dispersing capability for multivalent cations (calcium, iron, etc.). 

By depolymerizing PET waste with a polyol and subsequently condensing the oligomeric product with a polycarboxylic acid or anhydride, polyester resins are produced which have wide industrial applications. Depending on the polyol and polycarboxylic acid or anhydride used, saturated resins, alkyd resins, or unsaturated resins are obtained. PET wastes have been used for the production of alkyd resins in water thinnable paints. The materials obtained from the reaction of PET with a mixture of fatty acids high in linoleic acid content and trimethylolethane have been used in the preparation of water-dispersible coatings. Products of the depolymerization of PET with trimethylolpropane and pentaerythritol are used in the manufacture of high-solids paints. In the first step, PET is depolymerized with trimethylopropane and pentaerythritol at temperatures of 230-240°C. The final paint compositions contain 30-50% of PET depolymerization products.12... 

Other studies reached similar results for chitosan citrate and other salts. For instance, Yao et al. exposed to 65 °C a chitosan lactate solution for film formation and then heated it at 85 °C and 5-10 mmHg for 3 hr, to obtain amide linkages [47,227]. This is just an extension of existing technology for cotton fabrics to the area of chitosan chemistry in fact, a number of polycarboxylic acids have been used as cross-linking agents by Yang and Andrews [228]. 

The theory of gelation (Flory, 1953,1974) has been summarized in Section 2.2.3. This theory regards gelation as the consequence of the random crosslinking of linear polymer chains to form an infinite three-dimensional network. The phenomenon is, of course, well illustrated by examples drawn from the gelation of polycarboxylic acids by metal ions. 

Begala, A. J. (1971). Interactions of cations with polycarboxylic acids. PhD Dissertation. Rutgers University, The State University of New Jersey. 

Kagawa, I. Gregor, H. P. (1957). Theory of the effect of counter ion size upon titration behavior of polycarboxylic acids. Journal of Polymer Science, 23, 477-84. 

Beech, D. R., Solomon, A. Bernier, R. (1985). Bond strength of polycarboxylic acid cements to treated dentine. Dental Materials, 1, 154-7. 

Peddy, M. (1981). The bond strength of polycarboxylic acid cements to dentine effect of surface modification and time after extraction. Australian Dental Journal, 26, 178-80. 

Esters of Q to Cn monocarboxylic acids [1288-1292], acid-methyl esters [1282], and polycarboxylic acid esters [1287], as well as oleophilic monomeric and oligomeric diesters [1293], have been proposed as basic materials for inverted emulsion muds. Natural oils are triglyceride ester oils [1844] and are similar to synthetic esters. Diesters also have been proposed [1293-1297]. 

C. G. Carter, R. P. Kreh, and L. D. G. Fan. Composition and method for inhibiting scale and corrosion using naphthylamine polycarboxylic acids. Patent EP 538969,1998. 

A. Malandrino, M. Andrei, F. Gagliardi, and T. P. Lockhart. A thermodynamic model for PPCA (phosphino-polycarboxylic acid) precipitation. In Proceedings Volume. 4th IBC UK Conf Ltd Advances in Solving Oilfield Scaling Int Conf (Aberdeen, Scotland, 1/28-1/29), 1998. 

H. Muller, C. P. Herold, S. von Tapavicza, and J. F. Fues. Huid borehole-conditioning agent based on polycarboxylic acid esters. Patent WO 9119771,1991. 

Citric acid and nitriloacetic acid (NTA) lanthanide complexes were used in the earliest ion exchange separations of lanthanides from fission product mixtures (Kf = 3.2 for Ce(H3 Cit.)3 and Kf = 10.8 for CeNTA2) (Sillen and Martell, 1964). More recently such polyamino-polycarboxylic acids as ethylenediaminetetraacetic acid (EDTA), 1,2-diaminocyclohexaneacetic acid (DCTA), and diethylenetriaminepentaacetic acid (DTPA) have been prepared. Their lanthanide complexes are very stable (Table 3) and have been widely used in analysis and separation of lanthanide mixtures. They have also been used experimentally to remove internally-deposited 144Ce and other radioactive lanthanide nuclides from animals and man (Foreman and Finnegan, 1957 Catsch, 1962 Balabukha et al., 1966 Palmer et al., 1968 among others). 

Microgels have been prepared from epoxy resins which were intramolecular-ly crosslinked by a polyalkylene polyamine/polycarboxylic acid for flexible, corrosion resistant coatings [354]. 

The category of builders consists predominantly of several types of materials -specific precipitating alkaline materials such as sodium carbonate and sodium silicate complexing agents like sodium triphosphate or nitrilotriacetic acid (NTA) and ion exchangers, such as water-soluble polycarboxylic acids and zeolites (e.g., zeolite A). 

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