Microinjection molding of thermoplastic polymers: morphological comparison with conventional injection molding

作者:Giboz Julien*; Copponnex Thierry; Mele Patrice
来源:Journal of Micromechanics and Microengineering, 2009, 19(2): 025023.
DOI:10.1088/0960-1317/19/2/025023

摘要

The skin-core crystalline morphology of injection-molded semi-crystalline polymers is well documented in the scientific literature. The thermomechanical environment provokes temperature and shear gradients throughout the entire thickness of the part during molding, thus influencing the polymer crystallization. Crystalline morphologies of a high-density polyethylene (HDPE) micromolded part (mu part) and a classical part (macropart) are compared with optical, thermal and x-ray diffraction analyses. Results show that the crystalline morphologies with regard to thickness vary between the two parts. While a 'skin-core' morphology is present for the macropart, the mu part exhibits a specific 'core-free' morphology, i.e. no spherulite is present at the center of the thickness. This result seems to be generated under the specific conditions used in microinjection molding that lead to the formation of smaller and more oriented crystalline entities.

  • 出版日期2009-2