Abstract
Consideration will be given to the structural characterisation of extruded foam profile made from polypropylene and polypropylene/polyethylene blends containing chemical blowing agents.
Emphasis will be given to the influence of blowing agent concentration on the melt rheology of foamable compositions combined with the effects of die geometry and processing conditions on the resulting density in the foamed state, before and after cooling of the melt. Cellular structure will be discussed in terms of the relative levels of open and closed cell content, the uniformity of cell distribution, determined by mercury penetration, porosimetry and microscopic techniques, and microstructural characterisation of the semi-crystalline polymeric phase.
Get full access to this article
View all access options for this article.