Startseite Effect of mixing conditions and polymer particle size on the properties of polypropylene/graphite nanoplatelets micromoldings
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Effect of mixing conditions and polymer particle size on the properties of polypropylene/graphite nanoplatelets micromoldings

  • Renze Jiang , Piyush Lashkari , Shengtai Zhou und Andrew N. Hrymak EMAIL logo
Veröffentlicht/Copyright: 12. Juli 2022
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International Polymer Processing
Aus der Zeitschrift International Polymer Processing Band 37 Heft 4

Abstract

In this study, properties of polypropylene/graphite nanoplatelets (PP/GNP) composites and corresponding micromoldings were systematically studied in terms of filler loading concentrations and mixing methods. PP of different forms, i.e., PP pellets and powders, were adopted to fabricate PP/GNP composites. Additionally, a comparative study of precoating GNP and PP powders using solvent-based solution blending and ultrasonication-assisted mixing was performed. Results showed that PP/GNP composites prepared using powder form PP resulted in at least one order of magnitude higher electrical conductivity than using pellet form PP and further reduced the percolation threshold from 12.5 to 10 wt%, which was related to the state of filler distribution within corresponding moldings. Morphology observations revealed that microparts prepared with powder-PP/GNP composites exhibited less preferential alignment of GNP particles along the flow direction when compared with those molded using pellet-PP/GNP counterparts, which was helpful in improving the overall electrical conductivity for PP/GNP micromoldings.

Keywords: conductive polymer composites; microinjection molding; microstructure; polypropylene
Corresponding author: Andrew N. Hrymak, Department of Chemical and Biochemical Engineering, The University of Western Ontario, London, ON, N6A5B9, Canada, E-mail:

  1. Author contributions: All the authors have accepted responsibility for the entire content of this submitted manuscript and approved submission.

  2. Research funding: The authors acknowledge the support of the Natural Sciences and Engineering Research Council of Canada Discovery Grants program (ANH). SZ is thankful for the support from the National Natural Science Foundation of China (52103040) and China Postdoctoral Science Foundation (2020M673217). RJ gratefully acknowledges support from Ontario Graduate Scholarship and Queen Elizabeth II Graduate Scholarship in Science and Technology.

  3. Conflict of interest statement: The authors declare no conflicts of interest regarding this article.

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Received: 2022-01-06
Revised: 2022-04-29
Accepted: 2022-05-07
Published Online: 2022-07-12
Published in Print: 2022-09-27

© 2022 Walter de Gruyter GmbH, Berlin/Boston

Artikel in diesem Heft

  1. Frontmatter
  2. Editorial
  3. Special issue for John Vlachopoulos
  4. Review Article
  5. Calendering of thermoplastics: models and computations
  6. Special Issue Contributions
  7. Film casting of polycarbonate/multi-walled carbon nanotubes composites using ultrasound-assisted twin-screw extruder: experiment and simulation
  8. Effect of mixing conditions and polymer particle size on the properties of polypropylene/graphite nanoplatelets micromoldings
  9. Extrusion foaming of linear and branched polypropylenes – input of the thermomechanical analysis of pressure drop in the die
  10. Improving the thickness distribution of parts with hybrid thermoforming
  11. Synergistic material extrusion 3D-printing using core–shell filaments containing polycarbonate-based material with different glass transition temperatures and viscosities
  12. TPU-based porous heterostructures by combined techniques
  13. Surfactant-free oil-in-oil emulsion-templating of polyimide aerogel foams
  14. Factors determining the flow erosion/part deformation of film insert molded thermoplastic products
  15. The extrusion of EPDM using an external gear pump: experiments and simulations
  16. News
  17. PPS News
https://doi.org/10.1515/ipp-2022-0004
Schlagwörter für diesen Artikel
conductive polymer composites; microinjection molding; microstructure; polypropylene

Artikel in diesem Heft

  1. Frontmatter
  2. Editorial
  3. Special issue for John Vlachopoulos
  4. Review Article
  5. Calendering of thermoplastics: models and computations
  6. Special Issue Contributions
  7. Film casting of polycarbonate/multi-walled carbon nanotubes composites using ultrasound-assisted twin-screw extruder: experiment and simulation
  8. Effect of mixing conditions and polymer particle size on the properties of polypropylene/graphite nanoplatelets micromoldings
  9. Extrusion foaming of linear and branched polypropylenes – input of the thermomechanical analysis of pressure drop in the die
  10. Improving the thickness distribution of parts with hybrid thermoforming
  11. Synergistic material extrusion 3D-printing using core–shell filaments containing polycarbonate-based material with different glass transition temperatures and viscosities
  12. TPU-based porous heterostructures by combined techniques
  13. Surfactant-free oil-in-oil emulsion-templating of polyimide aerogel foams
  14. Factors determining the flow erosion/part deformation of film insert molded thermoplastic products
  15. The extrusion of EPDM using an external gear pump: experiments and simulations
  16. News
  17. PPS News
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