Synthesis and study of polyol borates as corrosion inhibitors for steel and nonferrous metals

Interaction of sodium tetraborate with polyols, D-sorbitol and D-mannitol, in aqueous solutions was studied using the method of isomolar solutions, combined with polarimetry and conductometry. The possibility of synthesizing sodium sorbitol borate and mannitol borate with a 1: 1 component ratio was examined. The compounds obtained were tested as corrosion inhibitors for steel, copper, aluminum, and brass in an aqueous medium.     

Allylacetylenes and their derivatives as inhibitors of steel corrosion in sulfuric acid

New functionalized derivatives of allylacetylenes were prepared, and their ability to inhibit corrosion of St.3 low-carbon steel in 5 N sulfuric acid was studied. The effectiveness of inhibition of steel corrosion was studied in relation to the structure of acetylene derivatives, their concentration, and temperature of acidic medium.     

Copolymers of the C9 hydrocarbon fraction of liquid pyrolysis products with maleic anhydride and their esterification products as additives to paper pulp

The influence exerted by copolymers of the C₉ fraction of liquid pyrolysis products of petroleum raw materials with maleic anhydride and by their esterification products, added to paper pulp, on the main paper properties was examined.     

Synthesis of polychlorinated 2,5-dihydro-2-furanones from maleic anhydride

The reaction of maleic anhydride with phosphorus pentachloride, which leads to polychlorinated 2,5-dihydro-2-furanones, was studied. The structures of the compounds obtained were proved by means of spectral methods.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 600–601, May, 1991.     

3-Arylidene derivatives of 3H-furan-2-ones. Synthesis and reaction with maleic anhydride

The synthesis of 5-alkyl(aryl)-3-arylidene-3H-furan-2-ones was accomplished, and their reaction with maleic anhydride was studied. The configuration of the initial arylidene derivatives was established on the basis of the PMR spectra of the adducts obtained.N. G. Chernyshevskii Saratov State University, Saratov 410600. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1043–1047, August, 1997.     

Products of endic anhydride reaction with cyclic amines and their heterocyclization

Products of reaction between bicyclo[2.2.1]hept-5-ene-endo-endo-2,3-dicarboxylic anhydride (endic anhydride) and cyclic amines were obtained. By an example of one of amido acids a conformational analysis was performed and character of hydrogen bonds was studied using quantum-chemical calculations by PM3 procedure. endo-3-(4-Antipyrylcarbomoyl)-bicyclo[2.2.1]hept-5-ene-endo-2-carboxylic acid with a secondary amide group was converted into the corresponding carboximide which was epoxidized by performic acid.     

Synthesis diacetylenic ethers with terminal acetylenic bonds and studying them as inhibitors of steel corrosion in hydrochloric acid

New diacetylenic ethers with terminal acetylenic bonds were synthesized.     

Synthesis and evaluation of some new hydrazones as corrosion inhibitors for mild steel in acidic media

Research on Chemical Intermediates - Mild steel corrosion in HCl solution is an example of corrosion in acidic mediums. The ongoing research efforts to develop novel environmentally friendly...     

2-methylimidazole as a reagent for the photometric determination of maleic anhydride

The formation of molecular complexes of maleic anhydride with some substituted imidazoles in acetonitrile, dimethylformamide, and dimethyl sulfoxide was studied. The selection of 2-methylimidazole as a reagent for the photometric determination of maleic anhydride in the dimethyl sulfoxide medium was substantiated using kinetic and spectrometric techniques.     

Synthesis of maleic anhydride grafted polyethylene and polypropylene,with controlled molecular structures

This article discusses a new chemical route to prepare maleic anhydride (MA) grafted polyethylene and polypropylene polymers with controlled molecular structure, that is, MA grafted content and polymer molecular weight and composition distributions. The chemistry involves a free radical graft reaction of maleic anhydride with poly(ethylene‐co‐p‐methylstyrene) and poly(propylene‐co‐p‐methylstyrene) copolymers. Under a suspension reaction condition, the grafting reaction takes place selectively on the p‐methylstyrene units in the copolymer, due to high reactivity of p‐methyl group and favorable mixing between p‐methylstyrene units and chemical reagents in the swollen amorphous phases. The resulting polymer shows no detectable molecular weight change during the reaction, and the MA grafted content increases with the increase of initiator and p‐methylstyrene concentrations. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 1337–1343, 2000     

Copolymerization of 2-phenylvinyl alkyl ethers and maleic anhydride

A series of 2-phenylvinyl alkyl ethers (I) having as alkyl group methyl, ethyl, n-propyl, n-butyl, 2-methylbutyl, 3-methylpentyl, and optically active 1-methylpropyl of (S) absolute configuration, were copolymerized with maleic anhydride to alternating copolymers. The copolymerizations were carried out in bulk at 70°C in the presence of AIBN as initiator. Monomer I (R = Et) was also polymerized with lauroyl and benzoyl peroxide as initiator. The yield and molecular weight were highest when equimolar amounts of both monomers were used. The equilibrium constant of charge-transfer complex of monomer I (R = Et) and maleic anhydride was determined by the transformed Benessi-Hildebrand NMR method and has a value of 0.28 mole/1.     

Copolymerization of styrene with acrylonitrile and maleic anhydride

The complex formation constants for styrene (donor)-acrylonitrile (acceptor) and styrene-maleic anhydride (acceptor) systems are found to be 0.19 ± 0.01 and 0.28 ± 0.01 l/mol (¹H NMR, CCl₄, 298 K); the same values are characteristic for three-component systems of these monomers. The calculated ΔH ₀ values (the AM1 method) for styrene-acrylonitrile (C₁) and styrene-maleic anhydride (C₂) complexes comprise ?1.24 and ?2.30 kJ/mol. Changes in charges on double bonds of complex-bonded molecules are in the range from 0.001 to 0.006 au. These values are typical of π-π complexes. By analyzing the composition and rate of bulk copolymerization (333 K, 0.03 mol/l AIBN), we have shown that two complexes are involved in chain propagation: r ₁ = $ k_{2C_1 } /k_{2C_2 } $ = 0.26 ± 0.015 and r ₂ = $ k_{3C_2 } /k_{3C_1 } $ = 4.17 ± 0.143.     

Synthesis and luminescence properties of 4-(2-methyl-5-oxazolyl)naphthalic anhydride and the products of its condensation with aromatic amines

4-(2-Methyl-5-oxazolyl)naphthalic anhydridewas synthesized by heating -aminomethyl 5-acenaphthyl ketone hydrochloride with acetic anhydride and subsequent oxidation of the resulting 2-methy1-5-(5-acenaphthyl)oxazole. 4-(2-Methyl-5-oxazolyl)-naphthalic acid phenylimide and 4(3)-(2-methyl-5-oxazolyl)-7-oxo-7H-benzimidazo-[1,2-b]benzo[de]isoquinoline were obtained by condensation of 4-(2-methy1-5-oxazo-lyl)naphthalic anhydride with aniline and o-phenylenediamine. The coincidence of the directions of polarization of the C=N bond of the oxazole ring and the electronic shifts in the system of the anhydride and phenylimide molecules leads to an increase in the quantum luminescence yield.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1613–1615, December, 1977.     

Synthesis,X-ray structure and theoretical study of benzazole thioether and its zinc complex as corrosion inhibitors for steel in acidic medium

A ligand, 2-((benzo[d]thiazol-2-ylthio)methyl)-1H-benzo[d]imidazole, and its zinc complex have been synthesized. The structure of these compounds have been determined by spectroscopic techniques and single crystal X-ray diffraction. The corrosion inhibition study of these compounds for steel in 0.5 M H₂SO₄ medium has also been investigated using potentiodynamic polarization and EIS techniques. The quantum calculations were applied to investigate the relationship between the electronic properties and the corrosion inhibition efficiency of the two benzazoles derivatives. Surface analysis (XRF) indicated that the rust layer formed on the Cu-containing steels was enriched with Cu compounds. Polarization curves revealed that both inhibitors acted as a mixed-type inhibitor.     

Syntheses of monomethoxy polyethyleneglycol vinyl ether macromonomers and their radical copolymerization with maleic anhydride

In order to develop new biocompatible materials, monomethoxy polyethyleneglycol vinyl ethers (Me(EG)_n VE, n = 1–39) were synthesized from the corresponding monomethoxy polyethyleneglycol with acetylene. Successful purification of the macromonomers was performed by some adsorption procedures such as charcoal and ion-exchange resin treatments. The Me(EG)_n VE macromonomers were easily copolymerized with maleic anhydride (MAn) to give alternating copolymers. The copolymerization rates significantly depended on the ethyleneglycol chain length of the Me(EG)_n VE, resulting in relatively lower polymerization rate of higher MW macromonomer. The use of nonelectron donor solvent such as carbon tetrachloride led to higher yields and higher MW of copolymers.     

4-(5-Methoxy-2-oxazolyl)naphthalic anhydride and products of its condensation with aromatic amines

4-(5-Methyl-2-oxoazolyl)naphthalic anhydride was synthesized by condensation of 4-chloroformylnaphthalic anhydride with aminoacetone and subsequent cyclization of the resulting amide. Luminescing methyl-substituted N-phenylnaphthalimide and 1,8-naphthoylene-1,2-benzimidazple were obtained by condensation of this product with aniline and o-phenylenediamine, respectively. The relationship between the structures of the products and their electronic absorption and luminescence spectra was investigated.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 883–885, July, 1976.     

Ferrocene as an effective initiator for copolymerization of styrene with maleic anhydride

Ferrocene (Fc) was found to be an effective initiator for copolymerization of styrene (ST) with maleic anhydride (MAH). Copolymerization could be initiated by charge transfer complex formed between MAH as an electron acceptor and Fc as an electron donor. A good relationship between the formation of charge transfer complex and initiation activity was observed in the copolymerization of ST with MAH in various solvents. Overall energy of activation determined from an Arrhenius plot in dioxane was found to be 21.8 kJ/mol. © 1995 John Wiley & Sons, Inc.