The addition reactions of primary aliphatic and cycloaliphatic amines with 1-butyl acrylate have been investigated by means of near IR spectroscopy. The additions proceed contrary to the Markownikoff rule and are consecutive competitive reactions which can be treated as isolated reactions with respect to the considerable difference between rate constants of the individual steps. The value of rate constants determined from the spectral data have been compared and discussed in terms of the steric hindrance of alkyl groups which co-determines the reactivity of amines in the reactions investigated.
SynopsisThis article deals with the alkaline hydrolysis of ethyl acrylateacrylonitrile-divinylbenzene copolymer beads. Chemical changes during hydrolysis were evaluated by means of determination of total weight exchange capacity and of infrared spectroscopy. The influence of reaction temperature, concentration of the hydrolytic agent, degree of copolymers crosslinking as well as the influence of particle size upon the rate of hydrolysis were studied as a function of time. The mathematical and statistical calculations of experimental data were carried out. With respect to time dependence of hydrolysis of the copolymer functional groups, the average values of reaction rate constants as well as the values of assumed diffusion coefficients were calculated. The analysis is based on partial linearization of experimental results by means of semilogarithmic transformation. The empirical relations expressing dependences of reaction rate constants and of diffusion coefficients on conditions of hydrolysis were determined. INTRODUCTIONThe alkaline hydrolysis of esters and nitriles in organic chemistry of lowmolecular compounds has been well described.' However, this is not the case for hydrolysis of polymers containing the mentioned groups and especially for crosslinked copolymers in bead form. Let us make reference to some preceding articles. The above problems are described for instance by Smets and his cO-workers,2-4 by Stamberg and Se~Eik,~ or by Hynkova and Hraba16J as well as in patent l i t e r a t~r e .~~~ From the point of view of reaction kinetics the system of solid copolymer particles suspended in the liquid reaction medium is rather complicated. The reaction systems solid-liquid, especially those concerning heterogeneous catalysis, are described, e.g., by Aris,l0 who deals with these questions, however, only from the theoretical point of view. He has shown that the mathematical models of reacting solids in the liquid reaction medium can be exactly used only for isolated examples with simplified assumptions. That is why we have decided to describe the obtained results by means of empirical relations applicable especially to this investigated system in the given range. PROBLEM ANALYSISContrary to the hydrolysis of monomer esters and nitriles which is affected by the reaction temperature and by the time and concentration of the hydrolytic agent, only in case of crosslinked copolymer beads there is another important factor, namely, hydrolytic agent diffusion into the mass of the hydrophobic skeleton, which is affected by the skeleton network density and by the copolymer particle size. It means therefore that the studied questions are determined by diffusion of reaction components into copolymer particles and by subsequent chemical reaction between the liquid reagents and reactive groups fixed to the crosslinked copolymer. The subject under discussion in our case are the ester and nitrile groups hydrolyzed by the aqueous solution of sodium hydroxide. This article represents the continuation of results obtained in cas...
Die Bildung der Imidazoline von Fettsäuren wurde durch Reaktion von Diäthylentriamin mit Fettsäuren und Ölen untersucht. Mit Hilfe der IR‐ und UV‐Spektroskopie konnte bewiesen werden, daß sie bei Temperaturen von 150° bis 200° C entstehen. Bei dieser Temperatur entstehen gleichzeitig Aminoamide. Bei Temperaturen über 280° C tritt eine Zersetzung ein unter Bildung niedrigmolekularer Stickstoff‐Verbindungen eventuell bis zum Ammoniak.
i r e : , DipLChem. E. K r e j c a r una Dr.-ing. J . M l e r i v a A us dem Forschungsinstitut fur synthetiscfie Harze und Lacke, PardubicelCSSRMittels Infrarotspektroskopie wurde der EinfluD der Herstellungsbedingungen von Alkydharzen von Soja-und Leinol auf die cis-trans-Isomerisierung der ungesattigten Fettsauren studiert. Von groRter Wichtigkeit ist die Temperatur. Der hohere translsomerengehalt zeigt sich auch in den Eigenschaften der Alkydharze. L'isombrisation cis-trans des acides gras nonsaturbs pendant la prdparation des alkydesOn a etudie l'influence des conditions pendant la preparation des resines alkydes a partir des huiles de lin et de soya a I'isomerisation cis-trans des acides gras nonsatures a l'aide de la spectroscopie infra-rouge. La temperature a demontre l'influence capitale de toutes les conditions suivies. L e contenu eleve des isomeres trans se reflete dans les qualites des resines alkydes.
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