This paper reports on an attempt to use reactive extrusion with peroxide as a comfortable pathway for improvement of the crystallization of poly(3-hydroxybutyrate) in a melt spinning process. At first, rheological and thermal properties of the modified melts are determined in order to assess the effect of nucleation. Then spinning tests are carried out. Molecular weights and molecular weight distributions of the spun fibers are determined by chromatographic methods. Average crystallite size is measured by wide angle X-ray scattering. Thermal and textile properties of the spun PHB fibers are also determined. An estimation of the improvement of the crystallization in the spinline and of the inhibition of the secondary crystallization in the fibers from the use of the described way of reactive extrusion is given.

The authors prepared crosslinkable toughened polypropylene to be used for simultaneous spinning of hybrid yarn and the preparation of continuous glass fiber-reinforced polypropylene composites by filament winding to be consolidated by compression molding. A subsequent electron treatment aims on crosslinking of matrix as well as enhancement of interfacial adhesion in the interphase of glass fiberreinforced polypropylene composites. The authors evaluate the crosslinking behavior as well as the tensile properties of crosslinkable toughened polypropylene. Finally, the authors use transverse tensile test and single fiber pull-out test in order to study the effect of matrix modification and electron treatment on continuous glass fiber-reinforced polypropylene composites as well as on single glass fiber polypropylene model microcomposites.

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Precipitated calcium carbonates (PCC) of different particle morphologies were used as appropriate carrier particles for post-processing crosslinking reactions. Optimum particle morphology and size were estimated for preparation of dry liquids (DLs). The DLs were tested in three different typically crosslinking reactions of polymers.

Als Modellsysteme für sulfidierte und oxydativ regenerierte Al2O3‐Trägerkatalysatoren wurde Aluminiumoxid auf unterschiedliche Weise mit Schwefelsäure modifiziert. Aus den Untersuchungen zur temperaturprogrammierten Reduktion geht hervor, daß der Schwefel bei Temperaturen zwischen 500 und 750°C durch Wasserstoff bis zum Sulfid reduziert und zum größten Teil als H2S desorbiert wird, in geringem Ausmaß aber auch an der Al2O3‐Oberfläche adsorbiert verbleibt.