Stabilisierung von UHMW-PE mit alpha-Tocopherol unterhalb des Schmelzpunkts

Translated title of the contribution: Stabilization of UHMW-PE with alpha-tocopherol below the melting point

Helene Hopfer

    Research output: ThesisDiploma Thesis

    Abstract

    In previous projects two methods for stabilizing crosslinked ultra high molecular weight polethylene (UHMW-PE) above the melting point have been presented. Method 1 operates at low pressure levels, while method 2 uses supercritical carbondioxide (CO2) at very high pressure levels for loading the polymer with vitamine E. In this work the suitability of both methods concerning a stabilization below the melting point at 138°C was investigated. For method 2 various impregnation temperatures, impregnation pressure levels, impregnation periods and alpha-tocopherol concentrations were used to achieve optimal stabilization conditions. Secondly, the depressurization process was optimized. A too fast decrease of pressure results in damaged samples due to expanding CO2. For method 1 various diffusion times were tested. Analyzation methods such as differential scanning calorimetry (DSC), fourier transformation infrared-spectroscopy (FTIR, transmissionelectron micoscopy (TEM), light microscopy and digital fotography were used for detection of crystallinity, alpha-tocopherol distribution and microstructural changes and damages respectively. Both methods are well suited to stabilize UHMW-PE below its melting point, with better results for method 2.
    Translated title of the contributionStabilization of UHMW-PE with alpha-tocopherol below the melting point
    Original languageGerman
    Supervisors/Advisors
    • Lederer, Klaus, Supervisor (internal)
    • Wolf, Christian, Co-Supervisor (external)
    Award date30 Jun 2006
    Publication statusPublished - 2006

    Bibliographical note

    embargoed until null

    Keywords

    • polyethylene
    • ultra high molecular weight UHMW-PE crosslinked carbondioxide
    • supercritical CO2 alpha-tocopherol vitamine E stabilization

    Cite this