New catalysts B–P–V–W–Ox/SiO2 of gas-phase condensation of acetic acid from formaldehyde to acrylic acid on an industrial carrier of stable chemical composition (colloidal silicon oxide, Aerosil A-200) were synthesized. It is shown that the hydrothermal treatment of the carrier allows to increase the activity and selectivity of the catalyst in the reactions of aldol condensation of acetic acid with formaldehyde.
In this paper the method of modification of polypropylene planar surfaces and microfibers through covalent grafting of a polyacrylic acid nanolayer by a free radical mechanismis presented.After grafting of the nanolayers, the hydrophobic surface of the polypropylene acquires hydrophilic properties. These changes are confirmed by the alteration of the free surface energy on the planar surfaces and by the increase of retentioned water by the microfibers before and after modification.
Due to the low efficiency of known catalysts of aldol condensation of acetic acid with formaldehyde, studies aimed at creating new or improving existing catalysts of this process are relevant. Creation of active and selective condensation catalysts will facilitate the industrial introduction of acrylic acid production by means of aldol condensation.
Catalytic performance of Se-containing organic substances, namely methylseleninic acid, benzeneseleninic acid, phenylselenol and diphenyldiselenide, has been tested as potential catalysts for unsaturated aldehydes oxidation by hydrogen peroxide. All tested substances proved to be active in the acrolein oxidation reaction but showed different efficiency regarding used solvents and the products of reaction – acrylic acid or methyl acrylate. Optimal catalyst, reaction conditions and solvent for acrylic acid synthesis have been determined.
The process of aldol condensation of acetic acid with formaldehyde in the presence of solid oxide catalysts in gas phase has been investigated. The optimum content of active components in the catalyst and the optimum content of promoter in the catalyst for the process of acrylic acid obtaining has been determined. Досліджено процес альдольної конденсації оцтової кислоти з формальдегідом у присутності твердих оксидних каталізаторах у газовій фазі.
The paper an approach to obtained compositions materials on the base of carboxyl-contained hydrocarbon olygomers. The influence of the temperature, time of structures, and the type of the sanctions on the mechanical, physical and chemical characteristics synthetized coatings. The major features of the process have been determined and recommendation for a production with of new protective polymer compositions. Стаття присвячена одержанню захисних композиційних матеріалів на основі карбоксилвмісних вуглеводневих олігомерів.
The process of acrylic acid obtaining by gas-phase condensation of acetic acid with formaldehyde over fumed silica based catalysts has been investigated. The effect of catalyst treatment method on its catalytic properties has been determined. The optimal catalyst for acrylic acid obtaining has been defined.
Poly(o-toluidine) doped with acrylic acid and without it was synthesized by using chemical oxidative polymerization technique. With the help of this method the polymer, poly(o-toluidine) was synthesized in the form of emeraldine salt. The oxidizing agent used for this method is the ammonium persulphate .The polymer products were characterized by UV-Visible and FTIR spectroscopy. The polymer, poly(o-toluidine) doped with acrylic acid was highly soluble in common organic solvents like m-cresol, NMP, DMF etc.
The saturated vapor pressure of the acrylic acid solutions in 1,2-dichloroethane and acetic acid was measured by static tensimetric method in the temperature range of 295 to 355 K. The composition of the equilibrium phases as well as the activity coefficients (γ1 and γ2) were received from the experimental measurements of the temperature-dependent saturated vapor pressure. Then we used the temperature and concentration dependent activity coefficients to calculate the excess thermodynamic functions of the solutions mixing (HE, GE, SE).
Emeraldin salt of polyaniline was synthesized by chemical oxidative polymerization method; this salt is soluble in common organic solvents. The obtained results are discussed with reference to lactic acid doped polyaniline. It has been observed that acrylic acid doped polyaniline is comparatively more soluble than polyaniline doped with lactic acid in common organic solvent such as m-cresol, NMP (N-methyl pyrrolidinone), DMSO, DMF, etc. The acrylic acid doped polymer prepared using lactic acid is comparatively more soluble in m-cresol and NMP than the polyaniline without acrylic acid.