PREPARATION AND CHARACTERIZATION OF AMPHI PHILIC MEMBRANES WITH LYOTROPIC MESOPHASES FOR SIMULATION OF SKIN PERMEATION RESISTANCE

New amphiphilic polymer networks based on methacrylates with amphiphil ic side-chains were prepared by cross-linking. Undecanol was the lipop hilic part and tetraoxyethylen the hydrophilic part of the side-chain. The cross-linking was performed by a similarly derived amphiphilic di methacrylate connecting structure. To characterize the relevant membra ne features, like solvatation, degree of cross-linking, phase behavior and glass transition temperature, predominantly the swelling properti es in water as well as in certain organic solvents, but also polarisat ion microscopic examinations were used. It was intented to assess the dependence of these parameters from the degree of cross-linking. For t his reason the different systems were ranked accordingly to their cros s-linking. Their swelling degree was determined in the indifferent dio xane as swelling medium. In the binary phase diagram with water the sy stems show a prominent laminary phase in the area with water contents of about 20-80% up to a maximum temperature of 35 degrees C. The phase behavior was also confirmed by thermal analysis, and the results of s welling measurements in water. Despite the relatively small hydrophili c part of the molecule, the swelling of the tested new cross-linked sy stems is more intensive in water than in nonpolar organic solvents. Th e swelling characteristics and phase behavior show a certain comparabi lity to the human skin.