Die unter präparativen Aspekten wichtigste Erkenntnis der Untersu‐chungen ist, daß die Copolymerisation ürber komplexierte Monomere iiber den gesamten Verlauf kontrolliert werden kann, und nicht– wie in der Literatur beschrieben – spontan einsetzt; von grundsltzlich‐ er Bedeutung ist der totale Ausschluß van Oxidationsmitteln (Sauer‐stoff, organische Peroxide) im System bevor die Polymerisation ge‐startet wird. Die Polyreaktion weist viele Merkmale der klassischen, nach einem Radikalkettenmechanismus ablaufenden Polymerisation auf, und sowohl Umsatz als auch Molgewichte köronnen durch entsprechende Wahl der Reaktionskomponenten und –bedingungen iiber einen weiten Bereich kontrolliert werden; zu einem umfassenden Verständnis der Elementarschritte der Polyreaktion sind jedoch noch weitere Unter‐suchungen erforderlich. Was die Eigenschaften der alternierenden Co‐polymeren anbelangt, so hat die Charakterisierung der synthetisier‐ten Polymeren gezeigt, daß das Eigenschaftsprofil deutlich von dem statistischer Copolymerer abweicht.Die Autoren danken dem Bundesministerium für Forschung und Technologie für diefinanzielle UnterstCitzung dieser Arbeiten. Den Herren Prof. Dr. H. Cherdron und Dr. L.L. Boöhm danken wir fürr wertvolle Hinweise und Diskussionen.
It is shown that n-butane, condensed in autoclave, can readily dissolve the anionic surfactant AOT (bis-2-ethylhexylsodium sulphosuccinate) and that this solution sohibilizes water up to Wo = molar ratio/water-AOT).The microemulsion can be transformed into a gel by sohibilizing gelatin in the water microphase. These microemulsion gels are characterized by a very high viscosity (several hundred poise). However, the partial vapour pressure of the n-butane component in the gel is as high as in the liquid state. Infrared studies show that part of the water in the gel is still flee.Stability diagrams of this system and ~H-NMR studies to assess the state of water are presented. Analogously to reverse micelles from liquid hydrocarbons, the chemical shift of water protons is shifted to higher fields with respect to bulk water. This effect increases with decreasing temperature and w0. At low w0 values (< 10), a part of the water in the micelles does not freeze even at -35 ~ Due to the rapid evaporation of n-butane from the gel, gelatin films can be prepared simply by casting. Differential scanning calorimetry studies of the gels (from n-butane as well as from isooctane and other hydrocarbons) show that the films have a thermal stability comparable with, and sometimes higher than, gelatin films prepared by conventional methods. Preliminary permeability studies of these films with solutions of amino acid derivatives and with gas such as nitrogen and helium are presented.
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