Monobasic alcohol-acids

The monobasic saturated aromatic acids include benzoic, hippuric, toluic acids (three structures), phenylaceiic. phenylchloracelic, and dimethylben-zoic acid. Among the monobasic unsaturated acids are cinnamic, atropic. and phenylpropiomc acids. The saturated phenolic acids include gallic and salicylic acids. The alcohol acids include amygdalic, tropic, and man-delic acids. One example of an unsaturated monobasic phenolic acid is coumaric acid. 

Bouveault, L., Blanc, G. Transformation of monobasic saturated acids into the corresponding alcohols. Bull. Soc. Chim. France 1904, 31,... 

Who is to decide whether carbolic acid is an indifferent alcohol or a monobasic acid If the formation of monobasic phenylsulfuric acid is taken as decisive, so that the basicity of carbolic acid is zero, then picric add is an exception to the law. If we proceed the other way, deriving from the formation of picric acid, etc., the view that carbolic acid is a monobasic acid, then phenylsulfuric acid... 

Properties Colorless liquid penetrating odor and taste. D 0.9394 (20/4C), bp 185.4C, refr index 1.4081 (20C), vap press 0.08 mm Hg (20C), fp -34C, flash p 205F (96C) (OC). Soluble in water, alcohol and ether. Undergoes reactions typical of normal monobasic organic acids. Combustible. Derivation With other C5 acids by distillation from valerian, by oxidation of n-amyl alcohol, numerous essential oils. 

Synthetic esters like polyol esters or neopentyl polyol esters are made from monobasic fatty acids and polyhedric alcohols with a neopentyl structure (see Figure 7.6). On these molecules, there are no hydrogen atoms on the beta carbon. This carbon is where thermal attack occurs on diesters and eliminating it improves the thermal stability of the molecule. Polyol esters have an increased number of ester groups versus diesters. This feature increases polarity, which will affect the lubricity of the oil at elevated temperatures and give it an advantage over PAOs. 

Alkyd resins have been defined as the reaction product of a polybasic acid and a polyhydric alcohol. This definition Includes polyester resins of which alkyds are a particular type. The specific definition that has gained wide acceptance is that alkyds are polyesters modified with monobasic fatty acids. In recent years, the term nonoil or oil-free alkyd has come into use to describe polyesters formed by the reaction of polybasic acids with polyhydric alcohols in non-stoichlometric amounts. These products are best described as functional saturated polyesters containing unreacted OH and/or COOH groups, and they are finding rapidly increasing uses in organic coatings. 

One can see that surfactants like esters of monobasic alcohols and higher acids give water-in-hydrocarbon emulsions the sedimentation stability of which is 3—5 minutes. Application of an antiflocculation additive leads to a significant increase in sedimentation stability of up to 10 hours. Note that emulsions stabilised by a nonionic like Span have a high coalescence stability there is no aqueous serum separated as a continuous layer within several months. 

Compatible resins used with N/C include non-drying alkyds (see Chapter 12), acrylic resins and many natural resins and derivatives, such as dammar and ester gum. Natural resins are mixtures of relatively low molecular weight chemicals, often of uncertain chemistry (see rosin. Chapter 12). Ester gums are produced by reacting polyhydric alcohols, e.g. glycerol, with rosin. An increase in molecular weight occurs, since more than one molecule of monobasic rosin acid will react with one molecule of the alcohol. Replacement of... 

Alkyd Condensation products of polybasic acids or anhydrides and polyhydric alcohols. Contains monobasic fatty acids... 

Substances discovered by Gerhardt include cumene, cuminol as the aldehyde of cumic acid, and cymene, styrene, anilides, sulphanilic acid, acetanilide, and the anhydrides of monobasic organic acids (1852, see p. 454). He introduced the names phenol, borneol, and glucoside. After Laurent s work on phenol (see p. 389) Gerhardt prepared it by heating salicylic acid with lime and showed that it is not a true acid (acide phenisique) but is related to the alcohols. In his work on anilides he represented oxamide, which the discoverer Dumas had correctly formulated as an amide, + N H, as containing the imide group NH, viz. + = +... 

In the case of sulphur trioxide-alcohol systems the conductivity-composition curve reveals a maximum at 1 4-5 sulphur trioxide/alcohol molar ratio showing that the adducts formed are highly solvated. There is no break in the curve at a molar ratio 1 3, There are, however, breaks at 1 2 and 1 1 sulphur trioxide/alcohol molar ratios. The potentiometric, conductomeuic and visual titrations show that sulphur trioxide solutions in these alcohols behave as monobasic acids against nitrogen bases and indicate that the stable species in alcohol solutions are the tetracoordinated alkyl hydrogen sulphates which are monobasic ionizable acids. 

Alkyd resins are prepared from polyhydric alcohols (three or more hydroxyls), polybasic acids, and monobasic fatty acids (saturated and unsaturated) [1]. They are soluble in hydrocarbon solvents and are used in the coating industry. Polyesters prepared from dihydric alcohols are not included in the area of alkyd resins in this chapter and have been described in Vol. I of this series [2]. 

The term rosin-based alkyd resins refers to alkyd resins in which all or a portion of the monobasic fatty acid is replaced by rosin (a mixture of diterpene resin acids and nonacidic components). Unmodified alkyd resins are polyester products composed of polyhydric alcohol, polybasic acid, and monobasic fatty acid. 

The term modified alkyd, which formerly was used to describe these products, now is associated with chemical modifications that are carried out during alkyd preparation, and that incorporate chemical agents of types other than those included in the definition. For example, the term rosin-based alkyd resins or rosin-modified alkyd refers to alkyd resins in which all or a portion of the monobasic fatty acid is replaced by rosin. Unmodified alkyd resins are polyester products composed of polyhydric alcohol, polybasic acid, and monobasic fatty acid. When no fatty acids are used, or when they are completely replaced by other types of acid, the products can be considered as oil-free alkyds. 

Monobasic organic acids are decarboxylated to hydrocarbons having one atom of carbon less than the acid. Alcohols are dehydrated and the olefins obtained are hydrogenated to the corresponding hydrocarbons. These transformations are carried out in a reactor at 250-300°C. 

Reduction of esters of monobasic acids with sodium and absolute ethyl alcohol (method of Bouveault and Blanc), for example ... 

Place 1 0 g. of the monobasic acid and 2 g. of aniline or p-toluidine in a dry test-tube, attach a short air condenser and heat the mixture in an oil bath at 140-160° for 2 hours do not reflux too vigorously an acid that boils below this temperature range and only allow steam to escape from the top of the condenser. For a sodium salt, use the proportions of 1 g. of salt to 1 5 g. of the base. If the acid is dibasic, employ double the quantity of amine and a reaction temperature of 180-200° incidentally, the procedure is recommended for dibasic acids since the latter frequently give anhydrides with thionyl chloride. Powder the cold reaction mixture, triturate it with 20-30 ml. of 10 per cent, hydrochloric acid, and recrystallise from dilute alcohol. 

The benzene - alcohol method is useful for the esterification of valuable monobasic acids, but the b.p. of the ester must be at least 50° higher than that of benzene, for example ... 

The catalyst, which may be regarded as complementary to Raney nickel (Section VI,5) is largely used for the hydrogenation of esters (esters of monobasic and of dibasic acids to alcohols and glycols respectively) ... 

A freshly made solution behaves as a strong monobasic acid. Neutralized solutions slowly become acidic because of hydrolysis to monofluorophosphoric acid and hydrofluoric acid. The anhydrous acid undergoes slow decomposition on distillation at atmospheric pressure, reacts with alcohols to give monofluorophosphoric acid esters, and is an alkylation (qv) and a polymerization catalyst. 

Polyol Esters. Polyol esters are formed by the reaction of an alcohol having two or more hydroxyl groups, eg, a polyhydric alcohol and a monobasic acid. In contrast to the diesters, the polyol in the polyol esters forms the backbone of the stmcture and the acid radicals are attached to it. The physical properties maybe varied by using different polyols or acids. Trimethylolpropane [77-99-6] C H O, and pentaerythritol [115-77-5] are... 

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