Phosphonocarboxylic acids

These types of polymers are similar to phosphonates and some actually are phosphonates, despite attempts to confuse the issue by the use of alternative names. They tend to exhibit varying degrees of both deposit-control and corrosion-control properties. Several PCA polymers were introduced in the 1980s and further developed in the 1990s and were termed phosphinocarboxylic acids. Most were, in fact, acrylic acid/organic phosphate polymers, but with a C P C bond (the phosphonates have a C P O bond). In the 1990s some low phosphorus content phosphonocarboxylic acid PCAs have been introduced. Structures for the different chemical PCAs, types 16 and 4, are shown in Figure 5.5. 

A newer type of PCA chemistry now available in the marketplace is a 55% actives, phosphonocarboxylic acid blend (Bricorr 288 from Albright Wilson/Rhodia). Although it has some deposit-control properties in soft and medium hardness waters, its primary application is as an organic corrosion inhibitor. 

Low phosphorus content, CaCOi scale inhibitor and corrosion inhibitor PCA (Type 288) Phosphonocarboxylic acid blend example Bricorr 288... 

Szczepanska-Konkel M, Yusufi ANK, VanScoy M, Webster SK, DousaTP. Phosphonocarboxylic acids as specific inhibitors of Na -dependent transport of phosphate across renal brush border membrane. J Biol Chem 1986 261 6375-6383. 

Pudovik, A.N., New method of synthesis of esters of phosphonocarboxylic acids and their derivatives, Dokl. Akad. Nauk SSSR, Ser. Khim., 85, 349, 1952 Chem. Abstr, 47, 535li. 1953. 

Kamai, G., and Shugurova, E.L, Alkyl esters of phosphonocarboxylic acids, Dokl. Akad. Nauk SSSR, 72, 301, 1950 Chem. Abstr, 45. 542c, 1951. 

Kamai, G., and Bastanov, E.S., Some new esters of phosphonocarboxylic acids and their derivatives, Zh. Obshch. Khim., 21, 2188, 1951 Chem. Abstr, 46, 7517g, 1952. 

Dingwall, J.G.. Cook. B., and Marshall, A., Phosphonocarboxylic acid compounds, Ciba-Geigy A.G., German Patent Appl. DE 2756678, 1980 Chem. Abstr. 89, 129707, 1978. 

A very large amount of NMR spectroscopic data has been collected during the year under review. The presentation of data in addition to data is now almost routine. NMR spectroscopic studies have now been presented for phosphonocarboxylic acids and their esters,some new phosphinic amides, and for Lawesson s reagent (solid and solution data). A spectroscopic study of the dimer of the nitrile oxide (401) suggested the structure (402). 1-(1-Naphthalenyl)ethylamine and ephedrine are recommended for the NMR spectroscopic determination of the enantiomeric composition of (1-aminoalkyl)-phosphonates, but of quinine and rert-butylphenylphosphinothioic acid, only the former was effective for the chiral resolution of the diethyl esters in the determination of e.e.s of (2-hydroxyalkyl)phosphonates. Conformational analyses, based on NMR spectroscopic data, have been carried out for dialkyl (2-hydroxyalkyl)phosphonates. ... 

Ochoa, N., Moran, R, and Pebere, N., The synergistic effect between phosphonocarboxylic acid salts and fatty amines for the corrosion protection of a carbon steel. Journal of Applied Electrochemistry, 2004. 34(5) 487-493. 

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