Charakterisierung von vernetztem polybutadien durch olefin-metathese

Cis-1,4-polybutadiene crosslinked with dicumylperoxide was characterized chemically by methathetical degradation and physically by unidirectional compression and swelling in benzene with respect to the structure of network. The metathetical degradation with a low molecular olefine in the presence of a catalyst like WCl₆/(CH₃)₄Sn delivers GC detectable fragments of network chains and GPC detectable fragments of crosslinks. The analytical data of the crosslink fragments are compatible with high functionality (f = 18) and a vulcanization via cyclizing polyreaction of 1,4-double bonds. The network chain concentrations ν determined by degradation and compression are comparable. The Flory-Huggins-interaction parameter χ can be estimated from swelling and compression measurements in dependence of the volume fraction of polymer φ.     

Charakterisierung von Fetten durch physikalische Methoden

Characterization of Fats by Physical Methods Properties of fats that are used for icings can be characterized by following determinations: 1. Temperature difference between beginning and end of the intensive process of melting, which can be read from the melting curve obtained by Fus-O-mat®. 2. Rate of growth of this curve in °C/min at region of 10°–15°C, in order to detect minimum partial melting. 3. Amount of crystalline glycerides which is separated from a solution of the fat in acetone (1 + 5) at 5°C. Thermal studies on fats give much more reproducible results if a uniform method of pre-crystallization from a petroleum solvent is adopted rather than tempering as practiced so far. The methods described are also applicable to the investigation of fats extracted from icings and chocolates. Lecithin contents, as generally found, do not affect the results.     

Entwicklung eines Mikrotrennungsganges für Tenside durch Kombination von Trägerelektrophorese und Dünnschichtchromatographie I

A Micro Separating Procedure for Surface Active Agents by Combination of Carrier-Electrophoresis and Thin-Layer Chromatography I A non expensive separating procedure is described for surface active agents used in textile finishing processes. Three different procedures are necessary: The extractive collection is followed by electrophoresis into the different loaded groups. Further separation is done by thin-layer chromatography, by means of general indicating reagents for the uniform loaded groups and special reagents for the functional groups, sometimes in connection with micro splitting reactions. The method supplies qualitative and semiquantitative conclusions.     

Herstellung von Tränkkatalysatoren als verfahrenstechnische Aufgabe

Production of impregnated catalysts as a chemical engineering task . Impregnated catalysts are the result of manufacturing processes involving a complex interplay of diffusion, viscous flow by capillary action, and solid state reactions. A knowledge of physical chemistry and drying technology permits systematic prediction of the necessary production steps in some detail. It is similarly possible to reduce the number of experiments needed to determine which variables are important and therefore have to be optimized. Thus it is at least possible to distribute the active components in the structure of the carrier in a manner that relates appropriately to the reaction requirements. This systematic prediction is limited in special cases where the active component of the catalyst changes its chemical nature during production. An example of this is when a catalyst requires an activation step.     

Optische Methoden zur Charakterisierung von hochpolymeren Fasern. 2. Kennzeichnung von Oberflächen durch Specklemeßmethoden.

The surface roughness of textile materials is of great influence on textile processing and practical applications. Speckle-techniques are common for integral, contactless, and non-destructive characterization of metallic surfaces. The scope of this work was to apply the analysis of the contrast of the speckle patterns and the dichromatic speckle correlation to measurements of the roughness of polymer surfaces. For this purpose it was of importance to study the influence of the optical properties of the polymer samples on the characteristics of the speckle field. Methods for measurements on filaments, yarns, and fabrics are discussed.