International Journal of Plastics Technology

, Volume 21, Issue 2, pp 239–251 | Cite as

Improvement on the surface quality of microcellular injection molded parts using microcellular co-injection molding with the material combinations of PP and PP-GF

  • Edward Suhartono
  • Shia-Chung Chen
  • Yung-Hsiang Chang
  • Jen-An Chang
  • Kuan Hua Lee
Research Article


Microcellular co-injection molding technology can completely encase the poor surface of a MuCell part. Using this technology, the effects of PP and PP-GF (10-wt% GF) combinations on the surface quality were investigated. For comparators, conventional, MuCell, and co-injection molded parts were also processed using constant injection parameters and varied material combinations. The surface quality was inspected both qualitatively via visual appearance and quantitatively via surface gloss. In addition, the weight reduction was also measured to ensure a successful microcellular structure generation inside the core. The results show that microcellular co-injection molded PP/PP-GF (skin/core) is the optimal combination with 4.2% weight reduction over co-injection PP/PP-GF, a similar surface appearance and surface gloss (60.9 GU) comparable to its solid PP counterpart, and 46.7% higher surface gloss than MuCell PP-GF. In addition, its specific dimensionless surface gloss is ranked first among all material combinations.


Microcellular injection molding Co-injection molding Weight reduction Surface quality Glass fiber 



This research was supported by R&D Center for Mold and Molding Technology, Chung Yuan Christian University, Taiwan.


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Copyright information

© Central Institute of Plastics Engineering & Technology 2017

Authors and Affiliations

  • Edward Suhartono
    • 1
    • 2
  • Shia-Chung Chen
    • 1
    • 2
  • Yung-Hsiang Chang
    • 1
    • 2
  • Jen-An Chang
    • 1
    • 2
  • Kuan Hua Lee
    • 1
    • 2
  1. 1.Department of Mechanical EngineeringChung Yuan Christian UniversityTaoyuan CityTaiwan
  2. 2.R&D Center for Mold and Molding TechnologyChung Yuan Christian UniversityTaoyuan CityTaiwan

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