Microcellular injection molding of foamed engineering plastic parts with high dimensional accuracy

Yu‐Teng Feng; Haiying Zhan; Hao‐Yang Mi; Maxwell Fordjour Antwi‐Afari; Youfu Chen; Laifa Gu; Binbin Dong; Chuntai Liu; Changyu Shen

doi:10.1002/app.54336

Microcellular injection molding of foamed engineering plastic parts with high dimensional accuracy

Yu‐Teng Feng, Haiying Zhan, Hao‐Yang Mi, Maxwell Fordjour Antwi‐Afari, Youfu Chen, Laifa Gu, Binbin Dong, Chuntai Liu, Changyu Shen

Research output: Contribution to journal › Article › peer-review

Abstract

Polyformaldehyde (POM) and Polyamide 66 (PA66) are engineering plastics with excellent mechanical properties and thermal stability. Producing microcellular injection molded POM and PA66 parts with high dimensional accuracy would be beneficial to reduce material cost and product quality. In this research, foamed POM and PA66 gear parts were fabricated by using microcellular injection molding with supercritical nitrogen as the blowing agent. Compared to conventional injection molded parts (parts that foaming is not involved), the foamed POM and PA66 gear parts achieved 5% and 10% average weight reduction, respectively. The foamed parts displayed a lower shrinkage ratio when compared to the solid counterparts, which was attributed to the cell expansion that offset part of the inward shrinkage stress. Moreover, POM gear parts with a higher crystallinity degree presented more serious shrinkage ratio compared to the PA66 gear parts, which contributed to the denser polymer molecular chains arrangement. The shrinkage ratio in both directions of PA66 foamed gear parts depended on the injection volume, and the lowest shrinkage ratio of 0.043‰ was obtained at the injection volume of 74 mm, when the polymer reached the maximum foaming ratio. The findings from this study could provide practical guidance for preparing microcellular injection molded products with high dimensional accuracy.

Original language	English
Article number	e54336
Journal	Journal of Applied Polymer Science
Volume	140
Issue number	35
Early online date	30 Jun 2023
DOIs	https://doi.org/10.1002/app.54336
Publication status	Published - 15 Sept 2023

Bibliographical note

Copyrigh © 2023 Wiley Periodicals LLC. This is the peer reviewed version of the following article: Feng, Y.-T., Zhan, H., Mi, H.-Y., Antwi-Afari, M. F., Chen, Y., Gu, L., Dong, B., Liu, C., Shen, C., J. Appl. Polym. Sci. 2023, e54336., which has been published in final form at https://doi.org/10.1002/app.54336. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions. This article may not be enhanced, enriched or otherwise transformed into a derivative work, without express permission from Wiley or by statutory rights under applicable legislation. Copyright notices must not be removed, obscured or modified. The article must be linked to Wiley’s version of record on Wiley Online Library and any embedding, framing or otherwise making available the article or pages thereof by third parties from platforms, services and websites other than Wiley Online Library must be prohibited.

Funding Information: The authors would like to acknowledge the financial support of the National Natural Science Foundation of China (52173049), the China 111 project (D18023), and the China Postdoctoral Science Foundation (2021M101797).

Keywords

cell morphology
dimensional accuracy
microcellular injection molding
shrinkage ratio

Access to Document

10.1002/app.54336

Cite this

@article{b42f339376a042b4b374522f858974de,

title = "Microcellular injection molding of foamed engineering plastic parts with high dimensional accuracy",

abstract = "Polyformaldehyde (POM) and Polyamide 66 (PA66) are engineering plastics with excellent mechanical properties and thermal stability. Producing microcellular injection molded POM and PA66 parts with high dimensional accuracy would be beneficial to reduce material cost and product quality. In this research, foamed POM and PA66 gear parts were fabricated by using microcellular injection molding with supercritical nitrogen as the blowing agent. Compared to conventional injection molded parts (parts that foaming is not involved), the foamed POM and PA66 gear parts achieved 5% and 10% average weight reduction, respectively. The foamed parts displayed a lower shrinkage ratio when compared to the solid counterparts, which was attributed to the cell expansion that offset part of the inward shrinkage stress. Moreover, POM gear parts with a higher crystallinity degree presented more serious shrinkage ratio compared to the PA66 gear parts, which contributed to the denser polymer molecular chains arrangement. The shrinkage ratio in both directions of PA66 foamed gear parts depended on the injection volume, and the lowest shrinkage ratio of 0.043‰ was obtained at the injection volume of 74 mm, when the polymer reached the maximum foaming ratio. The findings from this study could provide practical guidance for preparing microcellular injection molded products with high dimensional accuracy.",

keywords = "cell morphology, dimensional accuracy, microcellular injection molding, shrinkage ratio",

author = "Yu‐Teng Feng and Haiying Zhan and Hao‐Yang Mi and Antwi‐Afari, {Maxwell Fordjour} and Youfu Chen and Laifa Gu and Binbin Dong and Chuntai Liu and Changyu Shen",

note = "Copyrigh {\textcopyright} 2023 Wiley Periodicals LLC. This is the peer reviewed version of the following article: Feng, Y.-T., Zhan, H., Mi, H.-Y., Antwi-Afari, M. F., Chen, Y., Gu, L., Dong, B., Liu, C., Shen, C., J. Appl. Polym. Sci. 2023, e54336., which has been published in final form at https://doi.org/10.1002/app.54336. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions. This article may not be enhanced, enriched or otherwise transformed into a derivative work, without express permission from Wiley or by statutory rights under applicable legislation. Copyright notices must not be removed, obscured or modified. The article must be linked to Wiley{\textquoteright}s version of record on Wiley Online Library and any embedding, framing or otherwise making available the article or pages thereof by third parties from platforms, services and websites other than Wiley Online Library must be prohibited. Funding Information: The authors would like to acknowledge the financial support of the National Natural Science Foundation of China (52173049), the China 111 project (D18023), and the China Postdoctoral Science Foundation (2021M101797). ",

year = "2023",

month = sep,

day = "15",

doi = "10.1002/app.54336",

language = "English",

volume = "140",

journal = "Journal of Applied Polymer Science",

issn = "0021-8995",

publisher = "Wiley",

number = "35",

}

TY - JOUR

T1 - Microcellular injection molding of foamed engineering plastic parts with high dimensional accuracy

AU - Feng, Yu‐Teng

AU - Zhan, Haiying

AU - Mi, Hao‐Yang

AU - Antwi‐Afari, Maxwell Fordjour

AU - Chen, Youfu

AU - Gu, Laifa

AU - Dong, Binbin

AU - Liu, Chuntai

AU - Shen, Changyu

N1 - Copyrigh © 2023 Wiley Periodicals LLC. This is the peer reviewed version of the following article: Feng, Y.-T., Zhan, H., Mi, H.-Y., Antwi-Afari, M. F., Chen, Y., Gu, L., Dong, B., Liu, C., Shen, C., J. Appl. Polym. Sci. 2023, e54336., which has been published in final form at https://doi.org/10.1002/app.54336. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions. This article may not be enhanced, enriched or otherwise transformed into a derivative work, without express permission from Wiley or by statutory rights under applicable legislation. Copyright notices must not be removed, obscured or modified. The article must be linked to Wiley’s version of record on Wiley Online Library and any embedding, framing or otherwise making available the article or pages thereof by third parties from platforms, services and websites other than Wiley Online Library must be prohibited. Funding Information: The authors would like to acknowledge the financial support of the National Natural Science Foundation of China (52173049), the China 111 project (D18023), and the China Postdoctoral Science Foundation (2021M101797).

PY - 2023/9/15

Y1 - 2023/9/15

N2 - Polyformaldehyde (POM) and Polyamide 66 (PA66) are engineering plastics with excellent mechanical properties and thermal stability. Producing microcellular injection molded POM and PA66 parts with high dimensional accuracy would be beneficial to reduce material cost and product quality. In this research, foamed POM and PA66 gear parts were fabricated by using microcellular injection molding with supercritical nitrogen as the blowing agent. Compared to conventional injection molded parts (parts that foaming is not involved), the foamed POM and PA66 gear parts achieved 5% and 10% average weight reduction, respectively. The foamed parts displayed a lower shrinkage ratio when compared to the solid counterparts, which was attributed to the cell expansion that offset part of the inward shrinkage stress. Moreover, POM gear parts with a higher crystallinity degree presented more serious shrinkage ratio compared to the PA66 gear parts, which contributed to the denser polymer molecular chains arrangement. The shrinkage ratio in both directions of PA66 foamed gear parts depended on the injection volume, and the lowest shrinkage ratio of 0.043‰ was obtained at the injection volume of 74 mm, when the polymer reached the maximum foaming ratio. The findings from this study could provide practical guidance for preparing microcellular injection molded products with high dimensional accuracy.

AB - Polyformaldehyde (POM) and Polyamide 66 (PA66) are engineering plastics with excellent mechanical properties and thermal stability. Producing microcellular injection molded POM and PA66 parts with high dimensional accuracy would be beneficial to reduce material cost and product quality. In this research, foamed POM and PA66 gear parts were fabricated by using microcellular injection molding with supercritical nitrogen as the blowing agent. Compared to conventional injection molded parts (parts that foaming is not involved), the foamed POM and PA66 gear parts achieved 5% and 10% average weight reduction, respectively. The foamed parts displayed a lower shrinkage ratio when compared to the solid counterparts, which was attributed to the cell expansion that offset part of the inward shrinkage stress. Moreover, POM gear parts with a higher crystallinity degree presented more serious shrinkage ratio compared to the PA66 gear parts, which contributed to the denser polymer molecular chains arrangement. The shrinkage ratio in both directions of PA66 foamed gear parts depended on the injection volume, and the lowest shrinkage ratio of 0.043‰ was obtained at the injection volume of 74 mm, when the polymer reached the maximum foaming ratio. The findings from this study could provide practical guidance for preparing microcellular injection molded products with high dimensional accuracy.

KW - cell morphology

KW - dimensional accuracy

KW - microcellular injection molding

KW - shrinkage ratio

UR - http://www.scopus.com/inward/record.url?scp=85164151104&partnerID=8YFLogxK

UR - https://onlinelibrary.wiley.com/doi/10.1002/app.54336

U2 - 10.1002/app.54336

DO - 10.1002/app.54336

M3 - Article

SN - 0021-8995

VL - 140

JO - Journal of Applied Polymer Science

JF - Journal of Applied Polymer Science

IS - 35

M1 - e54336

ER -

Microcellular injection molding of foamed engineering plastic parts with high dimensional accuracy

Abstract

Bibliographical note

Keywords

Access to Document

Other files and links

Embargoed Document

Fingerprint

Cite this