Molecular Carboxylic Acids Research Articles

Determination of C1−C4 fatty acids as p-bromophenacyl esters using glass-capillary gas chromatography and electron-capture detection

A method for the determination of low relative molecular mass carboxylic acids (C1−C4) in water is reported. The acids are converted to p-bromophenacyl esters prior to a glass-capillary gas chromatographic separation. By utilizing electron-caputre detection the detectability is substantially improved compared to flame-ionization detection. A comparison of three different ways to treat the water samples and to produce the derivatives is made. It is shown that the α, p-dibromoacetophenone reagent decomposes to a small extent which limits the utility of the reagent. Nevertheless a detection limit for formic acid of approximately 2.5 mgl−1 is obtained. The method is applied to the determination of formic and acetic acids in a paper kraft water sample.

Complexation of poly(acrylic acid)s with uranyl ion

The complexation of uranyl ion (UO 2 2+) in aqueous solution with polymers containing carboxylic acid groups was studied potentiometrically. Overall formation constants of the uranyl complexes with poly(methacrylic acid) and crosslinked poly(acrylic acid) were much larger than those with the corresponding low molecular carboxylic acids. Decrease in the viscosity of the polymer solution on adding uranyl ion indicated that poly(acrylic acid) forms intra-polymer chelates with uranyl ion. The crosslinked poly(acrylic acid) adsorbed uranyl ions at higher efficiency than transition metal ions.

Transamidation reactions of carbon chain polymers

A study has been made of the reaction of poly(acrylic acid) and poly(methacrylic acid) with low molecular, unsubstituted amides and amides substituted on the nitrogen atom, and also of polyacrylamide and polymethacrylamide with low molecular carboxylic acids, in the temperature range of 120–220°. Polymers containing carboxylic and N,N-disubstituted amide groups are formed from the polyacids and N,N-disubstituted amides. In the other instances some imidization occurs in addition to transamidation.

Formation of silver mirror by photolysis of thin films of high molecular weight silver compounds

SILVER salts of carboxylic acids such as formic acid, acetic acid and oxalic acid1 became coloured in light. Similarly, suspensions of silver polyalkylacrylates produce various coloured colloidal solutions of silver in light2. These phenomena show that silver carboxylates are easily photolysed to separate silver. We have investigated the photolyses of silver salts of certain high molecular carboxylic acids such as polyacrylic acid, polymethacrylic acid, poly-L-glutamic acid3, alginic acid4, pectic acid5, carboxymethylcellulose and cellulose acetate phthalate, and we report that the smooth films of these silver salts form a silver mirror arising from photolytic silver on their surfaces. This method of producing a thin silver film on the polymer film may be of technical interest because of the optical and electrical properties of the irradiated film.

Solvent Extraction Behavior of Magnesium and Calcium in Versatic Acid-Amine Systems

Abstract Quantitative extraction of calcium and magnesium in high molecular weight carboxylic acid, versatic-9, and amine systems is reported. Butanol was used as diluent. The study includes the extraction behavior as a function of pH by controlled addition of amines, such as monoethanol amine, diethanol amine, and triethanol amine, the effect of diluent, solvent concentration, and different high molecular carboxylic acids such as versatic-10, versatic-911, and SRS-100. A comparison with the β-diketone-buffer-extraction system and versatic-9-buffer system has also been studied. The proposed method is very simple, and quantitative extraction has been achieved.