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The alcoholysis of acetyl chloride, propionyl chloride and butyryl chloride with some alcohols in acetone and toluene has been investigated by means of calorimetric measurements. Furthermore a comparison with benzoyl chloride has been made. In the case of i-propanol in acetone, a smaller rate constant has been found for the alcoholysis of propionyl chloride than for butyryl chloride. In contrast to this, almost equal rate constants have been determined for the reactions of these acyl chlorides with n-propanol and ethanol. In toluene, the rate constants for the reaction of acetyl chloride with all considered alcohols has the highest values under similar conditions but then decrease from acetyl chloride to butyryl chloride. The observed differences and the changes of rate constants are discussed and compared with literature data.

The alcoholysis of acetyl chloride under various reaction conditions has been investigated by isoperibolic calorimetry and HPLC-analysis. Non-linear kinetic evaluation has been realized by the program TA-kin 3.3 on the basis of temperature and concentration data. Depending on the excess of alcohol, different partial reaction orders are found. The reaction rate also depends on the basicity of the solvent. This could be caused by H-bonding with the alcohol increasing the activation energy. It was possible to distinguish between the kinetic parameters of the ethanolysis and the i -propanolysis of acetyl chloride in the evaluation of the alcoholysis of acetyl chloride by alcoholic mixtures at stoichiometric concentrations of the reagents. A partial order of n =0.5 for the alcohol, as determined in the evaluation of the single alcoholysis under these conditions, has been confirmed. The results show that heat accumulations are an important feature for the kinetic evaluation of reactions under the concentration conditions described.

The ethanolysis of acetyl chloride has been compared to the methanolysis and the hydrolysis, as well as to the reaction with n -propanol, n -butanol and n -pentanol in acetone and in toluene, to reveal chain-length effects. Pentanol, heptanol and nonanol have been included as well in the investigation, but at lower concentrations. Structural influences on the alcoholysis of acetyl chloride have been studied with the isomeric C 3 and C 4 -alcohols in acetone and in toluene. Furthermore, alcoholysis of acetyl chloride with some C 7 -alcohols and the reaction of benzoyl chloride with different types of alcohols have been investigated.

Investigations in chemical safety are necessary in case that the reaction course depends on changes of the reaction conditions sensitively. To break off a conversion in a hazardous situation, the precision calorimeter ACTRON 5 is equipped with two safety pumps. They empty and rinse the reactor with cold solvent. The pumps will be activated automatically. For testing the calorimeter the complex reaction of chloronitrobenzene with alkalined alcohol was used and break off at predefined conditions. The possibility of the kinetic estimation of these break-off files is shown.

Polyethers, which are produced by alcoholysis of oxiranes, are often used as solvents in chemical plants. The spectra of the products can be influenced by the choice of the catalyst (acid or base). The results of the base-catalyzed ethanolysis of 1,2-epoxybutane are displayed. The reaction was investigated calorimetrically by varying the molar ratio between ethanol and 1,2-epoxybutane, the starting temperature and the concentration of the catalyst sodium hydroxide. Additionally, the influence of the used alcohol will be shown in one example. To determine the activation parameters, the experiments were evaluated by the nonlinear software package TA-kin v3.3.

Differential scanning calorimetry is well suited to record heat productions of chemical and physical processes as data for the following kinetic analysis. To obtain kinetic parameters of complex reactions, nonlinear optimization methods have to be used. Such complex reaction systems are polymerizations. We tried to evaluate measurements of the epoxy cure and the polymerization of s-propiolactame with simple and complex models. In both cases the simple models did not produce satisfactory results. But by using complex models a successful fitting of the measured data was possible. Our investigation shows that the combination of DSC and modern nonlinear evaluation methods presents a suitable tool for the kinetic investigation of polymerizations.

Acetylation of different hexanediols as a complex reaction has been investigated by calorimetry. The calorimetric curves demonstrate that the reaction rate depends on the molecular structure. In case of 1,6- and 2,5-hexanediols, the activation parameters have been obtained by nonlinear evaluation procedures with the program TA-kin v3.3. The kinetic results show, that the formation of the diester is characterized by higher activation energies than that of the monoester.

Different ACTRON calorimeters were used to investigate the alcoholysis of phenyl isocyanate and acetyl chloride, and the reaction of o-chloronitrobenzene with alkaline alcohol. An example for a scenario to break off a reaction in a hazardous situation is given. At least it will be shown, that it is possible to evaluate an interrupted reaction to get the kinetic activation parameters.

Adiabatic calorimetry is a suitable method for investigations of reactions because the generated heat remains completely in the reactor. For the investigation of organic reactions, the adiabatic precision calorimeter ACTRON 5 is used. The alcoholyses of phenyl isocyanate and 1,2-butyleneoxide were investigated. The temperature-time course was estimated by means of the nonlinear program TA-kin. Inclusion of the concentration-time course in the estimation procedure led to an increase in the reliability of the parameters. Probes were taken during isoperibolic measurements and were analysed by means of HPLC.

Telomerization of isoprene is characterized by intense thermal effects. The reaction system di-μ-chlorobis(η3-allyl)-dipalladium(II): tri-n-butylphosphine: sodium methylate: isoprene=1∶2∶3∶200 in a solvent-mixture of methanol∶benzene=1∶3 is used as a model. It is concluded that reaction of the catalyst combined with reduction of Pd(II) is followed by the telomerization reaction. There is a marked influence of Pd and phosphine concentration in the catalyst as well as concentration of isoprene. Results are available to optimize technical applications.

The alcoholysis of triethylaluminium can be investigated by DTA in the liquid phase. The reaction enthalpy of the alcoholysis with primary alcohols is from −150 to −170 kJ mole−1 in tetrahydrofuran/toluene as solvent. The reaction rate in pure hydrocarbons is higher than in the presence of Lewis bases. The reaction mechanism is probably ofSE2 type and the reactivity decreases in the sequence primary, secondary, tertiary alcohol. In the second step of substitution the diethylaluminium alkoxides are less reactive than triethylaluminium because of the stronger association of the alkoxides. For the turnover of two moles of alcohol with one mole of triehylaluminium two DTA peaks appear in accordance with consecutive reactions.