Ageing of isotactic polypropylene due to morphology evolution, experimental limitations of realtime density measurements with a gradient column

摘要

Ageing in crystalline polymers is responsible for the deterioration of physical properties leading, for example, to a decrease in toughness and to dimensional changes that are to some extent responsible. for warpage and scrap production in injection molding. Since, it depends on the mutual transformation of stable and metastable phases, being always related to changes in morphological organization, it is here preferred to call it 'Morphological ageing'.