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Improvements on the tensile properties of microcellular injection molded parts using microcellular co-injection molding with the material combinations of PP and PP-GF

  • Research Article
  • Published:
International Journal of Plastics Technology

Abstract

One of the drawbacks of microcellular injection molded parts is lower part tensile strength and stiffness than solid parts. This is caused by a reduction in the effective cross-section area as the microcellular structure is generated inside the part. This study investigated how microcellular co-injection molding can add a solid skin layer, encapsulating the foamed core layer, to increase both part strength and stiffness. In addition to PP, PP-GF (10-wt% GF) was used for the reinforcing effect. The experiment used constant injection parameters and varied material combinations, and conventional, MuCell, and co-injection molded parts acted as comparators. The weight reduction was measured to ensure successful microcellular structure generation. The results show that microcellular co-injection molded PP/PP-GF (skin/core) is the optimal combination, reducing weight by 4.2% over co-injection PP/PP-GF, improving yield strength by 18.2% and Young’s modulus by 2.5% over MuCell PP-GF, yet with a brittle strain at break of 0.084 mm/mm.

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Authors and Affiliations

  1. Department of Mechanical Engineering, Chung Yuan Christian University, Taoyuan City, Taiwan

    Edward Suhartono, Shia-Chung Chen, Kuan-Hua Lee & Kuo-Jui Wang

  2. R&D Center for Mold and Molding Technology, Chung Yuan Christian University, Taoyuan City, Taiwan

    Edward Suhartono, Shia-Chung Chen, Kuan-Hua Lee & Kuo-Jui Wang

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  1. Edward Suhartono
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  2. Shia-Chung Chen
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  3. Kuan-Hua Lee
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  4. Kuo-Jui Wang
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Correspondence to Kuan-Hua Lee.

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Suhartono, E., Chen, SC., Lee, KH. et al. Improvements on the tensile properties of microcellular injection molded parts using microcellular co-injection molding with the material combinations of PP and PP-GF. Int J Plast Technol 21, 351–369 (2017). https://doi.org/10.1007/s12588-017-9190-7

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  • DOI: https://doi.org/10.1007/s12588-017-9190-7

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