Injection molding of polymer micro- and sub-micron structures with high-aspect ratios

  • A.-C. Liou
  • R.-H. ChenEmail author
Original Article


This work studies the injection molding characteristics of polymer micro- and sub-micron structures using demonstration mold inserts with micro- and sub-micron channels with high-aspect ratios. The effects of the injection molding parameters on the achievable aspect ratio of the micro- and sub-micron walls were investigated. Additionally, distinctive mold-filling behaviors and resulting defects were observed for various polymers, such as polymethyl methacrylate (PMMA), polypropylene (PP) and high-density polyethylene (HDPE). Experimental results reveal that the mold temperature determines the success of the injection molding of micro- and sub-micron walls. The satisfactory mold temperature for micro-injection molding significantly exceeds that for traditional injection molding. Moreover, the main injection pressure and the main injection time substantially affect the achievable aspect ratio of the micro- and sub-micron walls. Furthermore, unusual flow behaviors occur and poor molding results are obtained when PP and HDPE are used for micro-injection molding.


High-aspect ratio Injection molding  Micro-structures Molding characteristics  Sub-micron structures 


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Copyright information

© Springer-Verlag 2005

Authors and Affiliations

  1. 1.Department of Mechanical EngineeringNational Chiao Tung UniversityHsinchuTaiwan

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