Untersuchungen zum Abbau von PVC-Folien durch Wärme und Licht

The degradation of films of copolymers of vinyl chloride and carbon monoxide or oxygen by heat and light was investigated. With increasing carbonyl content the instability increases. The thermal degradation is accelerated by oxygen, the photodegradation is retarded. Due to the influence of light polyene sequences are formed on the surface layers of the polymer film. Therefore the lower layers are not damaged.     

Untersuchungen zum Verschleiß beim Spritzgießen von glasfasergefüllten Polyamiden. 3. Chemische Untersuchungen

For explanation of wear phenomena which take place during injectionmoulding of glass-fibre-reinforced polyamide 66 (PA 66), the chemical processes at the treatment of PA 66 with and without short-glass-fibres were investigated and compared with the results of pyrolysis tests. It was found that despite of the short retention times of the polyamide in the injection-moulding machine, a remarkable transamidation takes place towards reaching the equilibrium, dependent on temperature and water content. Additionally, carbon dioxide is produced as a reaction product, but only a little ammonia. Cyclopentanone and its condensation products are also decomposition products. Quantitative measurements indicate that the development of carbon dioxide is starting from the amidegroups, not from the carboxylic endgroups, but there are further investigations in this direction necessary in order to clarify the causes of carbon dioxide development.     

Untersuchungen zum Abbau von Nickelseifen während der Hydrierung von Rapssamenöl

Investigations of Degradation of Nickel Soaps During Hydrogenation of Rape Seed Oil The presence of free fatty acids in oils that are to be hardened leads generally to Ni-soap formation and has effects on the activity of the Ni-catalyst. In the submitted work first the solubility of the Ni-steatate in vegetable oil was investigated, which increases in a temperature range of 80–200° C of 0.01 to 0.38 mg Ni/g oil. In presence of a Ni-catalyst in the hydrogen reduction milieu Ni-soap is degradated in the first stage to about 80 % on an average. The reaction is reversible and for a Ni-soap content during the limits of solubility the state of equilibrium is adjusted to the average value of 70 %. The hydrogenation is advanced by a small amount of Ni-soap. The dependence of the rate constant on Ni-soap concentration was established.     

Chemische Untersuchungen an ozonisiertem Olivenöl

Chemical Investigations of Ozonized Olive-Oil Extensive investigations are necessary for application of ozonized olive-oil in the pharmaceutical field to identify the substances which result from ozonisation. All investigations were carried out in ethanol extracts because all substances, characteristic for ozonized olive-oil, are included in it. Thinlayer and gaschromatography turned out to be the best methods of analysis. The following classes of compounds could be detected qualitatively: monoglycerides, 1,2-diglycerides, 1,3-diglycerides, free long-chain carbonic-acids, triglycerides, carbonyl compounds and hydrocarbons. Among single components capronic acid, malondialdehyde, pelargonic acid and pelargonaldehyde could be identified.     

Chemische Untersuchungen an ozonisiertem Distelöl

Chemical Investigations of Ozonized Safflor Oil To continue the investigations of ozonized olive oil ozonized safflor oil was analysed with respect to some parameters which are important for medical application: peroxide value, malondialdehyd content, total fatty acids, fatty acids in the triglyceride fraction with and without peroxide groups in ozonized safflor oil. The high peroxide value and the increased amount of malondialdehyd with respect to ozonized olive oil was striking. Furthermore the high content of myristic acid in the oil or of linoleic acid in the triglyceride fraction, containing peroxide groups (content in safflor oil 36%) and lauric, myristic and oleic acid in the triglyceride fraction without peroxide groups.     

Untersuchungen zum Nachweis von Kakaobutter-Ersatzfetten

Investigations on the Detection of Cocoa Butter Substitutes Coberine, Calvetta and other fats prepared by fractionation, as well as Tenkawang fat have a fatty acid composition which is very similar to cocoa butter. Presence of fatty acids that do not occur in cocoa butter, ratio of C₁₆/C₁₈, as well as composition of sterol fraction serve for chemical identification of the above fats.     

Thermische Untersuchungen zum Formierungsverhalten des Katalysatorsystems Cobaltacetylacetonat-Triethylaluminium

Thermal Investigation of the Formation of the Catalyst System Cobalt Acetylacetonate – Aluminium Triethyl The formation of the Ziegler catalyst system cobalt-tris- and cobalt-bis-acetylacetonate with triethylaluminium was investigated by means of quantitative differential thermal analysis and calorimetry in solution. From DTA and heat flow curves qualitative and quantitative relations were determined between Al/Co-ratio and thermal reaction power. For both systems in both systems in the first step second order reactions are postulated and kinetic and thermodynamic parameters are evaluated, whereas the course and order of the following steps differ distinctively. For the complete reduction of one mole Co(III) or Co(II), respectively, every alkyl group of AlEt₃ is suitable.     

Untersuchungen zum reaktionsverhalten von polyacetylen mit dienophilen

Experiments designed to increase the long term stability of polyacetylene by reaction with dienophiles gave no indication of a Diels-Alder-reaction. The increase in weight observed in in situ reactions in the presence of Ziegler-Natta-catalyst is caused by a reaction between the catalyst and the dienophil, which gives insoluble products. This was clearly shown by infrared spectroscopy.