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Cross-sectional observation of a weak boundary layer in polytetrafluoroethylene (PTFE) using scanning electron microscope

Abstract

A weak boundary layer (WBL), at the surface of polymers, causes poor adhesion, but such a WBL has not been characterized or quantified. In this study, to characterize a WBL of polytetrafluoroethylene (PTFE), we observed a cross-section of PTFE using a scanning electron microscope and compared the surfaces and bulk sides. We observed voids on the surface of the PTFE but not on the bulk side. These voids existed up to 5 µm from the outermost surface of the PTFE. We defined a WBL by the presence or absence of voids and then concluded that the thickness of the WBL in PTFE was of the order of a single micrometer.

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References

  1. Schonhorn H, Hansen RH. Surface treatment of polymers for adhesive bonding. J Appl Polym Sci. 1967;11:1461–74.

    Article  Google Scholar 

  2. Bikerman JJ. Causes of poor adhesion: weak boundary layers. Ind Eng Chem. 1967;59:40–4.

    Article  CAS  Google Scholar 

  3. Miller ML, Postal RH, Sawyer PN, Martin JG, Kaplit MJ. Conditioning polytetrafluoroethylene surfaces for use in vascular prostheses. J Appl Polymer Sci. 1970;14:257–66.

    Article  CAS  Google Scholar 

  4. Dwight DW, Riggs WM. Fluoropolymer surface studies. J Colloid Interface Sci. 1974;47:650–60.

    Article  CAS  Google Scholar 

  5. Marchesi JT, Keith HD, Garton A. Adhesion to sodium naphthalenide treated fluoropolymers. part iii. mechanism of adhesion. J Adhes. 1992;39:185–205.

    Article  CAS  Google Scholar 

  6. Ryan ME, Badyal JPS. Surface texturing of PTFE film using non-equilibrium plasmas. Macromolecules. 1995;28:1377–82.

    Article  CAS  Google Scholar 

  7. Kim SR. Surface modification of poly(tetrafluoroethylene) film by chemical etching, plasma, and ion beam treatments. Appl Polym. 2000;77:1913–20.

    Article  CAS  Google Scholar 

  8. Sunkara V, Park DK, Cho YK. Versatile method for bonding hard and soft materials. RSC Adv. 2012;2:9066–70.

    Article  CAS  Google Scholar 

  9. Ohkubo Y, Ishihara K, Sato H, Shibahara M, Nagatani A, Honda K, et al. Adhesive-free adhesion between polytetrafluoroethylene (PTFE) and isobutylene–isoprene rubber (IIR) via heat-assisted plasma treatment. RSC Adv. 2017;7:6432–38.

    Article  CAS  Google Scholar 

  10. Ohkubo Y, Ishihara K, Shibahara M, Nagatani A, Honda K, Endo K, et al. Drastic improvement in adhesion property of polytetrafluoroethylene (PTFE) via heat-assisted plasma treatment using a heater. Sci Rep. 2017;7:9476.

    Article  Google Scholar 

  11. Ohkubo Y, Endo K, Yamamura K. Adhesive-free adhesion between heat-assisted plasma-treated fluoropolymers (PTFE, PFA) and plasma-jet-treated polydimethylsiloxane (PDMS) and its application. Sci Rep. 2018;8:18058.

    Article  Google Scholar 

  12. Ohkubo Y, Shibahara M, Nagatani A, Honda K, Endo K, Yamamura K. Comparison between adhesion properties of adhesive bonding and adhesive-free adhesion for heat-assisted plasma-treated polytetrafluoroethylene (PTFE). J Adhes. 2020;96:776–96.

    Article  CAS  Google Scholar 

  13. Brewis DM. Adhesion to polymers: how important are weak boundary layers? Int J Adhes Adhes. 1993;13:251–56.

    Article  CAS  Google Scholar 

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Acknowledgements

The author would like to thank Enago (www.enago.jp) for the English language review.

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YO, KE, and KY supervised the work. YS, MN, and YO performed the washing, cooling, and cutting PTFE sheets. YS performed the SEM observation with MN and YO. All authors contributed to the scientific discussion and manuscript preparation. YS wrote the manuscript.

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Correspondence to Yuji Ohkubo.

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The authors declare no competing interest.

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Seto, Y., Nishino, M., Okazaki, Y. et al. Cross-sectional observation of a weak boundary layer in polytetrafluoroethylene (PTFE) using scanning electron microscope. Polym J 54, 79–81 (2022). https://doi.org/10.1038/s41428-021-00535-6

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  • DOI: https://doi.org/10.1038/s41428-021-00535-6

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