JJAP Conference Proceedings

JJAP Conf. Proc. 7, 011202 (2018) doi:10.7567/JJAPCP.7.011202

Study of the porosity in cellulose acetate membranes by 3γ annihilation of positrons

Shuai Wang1, Cheng Yin1, Zhe Chen1, Yong Zhang1, Jiangyu Wu1, Hongjun Zhang2, Jizhong Hai3, Xiaobo Yang3, Haiping Liu3

  1. 1Hubei Key Laboratory of Plasma Chemistry and Advanced Materials & Department of Material Science and Engineering, Wuhan Institute of Technology, Wuhan 430205, China
  2. 2Division of Applied Physics, Faculty of Pure and Applied Science, University of Tsukuba, Tsukuba, Ibaraki 305-8573, Japan
  3. 3Key Laboratory of Salt Lake Resources Integrated Utilization of Qinghai, Qinghai Salt Lake Industry Co., Ltd., Golmud 816000, China
  • Received September 25, 2017
  • PDF (294 KB) |


A series of cellulose acetate membranes with different porosities were prepared. The porosity of the membrane was adjusted by adding different molecular weights and contents of polyethylene glycol (PEG), which acts as pore-forming agent in the preparation process. Positron annihilation lifetime measurement and γ-ray energy spectroscopy were employed to evaluate the porosities of the membranes. The lifetime results indicate the size of the free-volume holes in all the membranes are nearly the same. The 3γ annihilation results suggest that, with the increase of porogen content: if the molecular weight of the porogen is low (PEG200, PEG400), pore combination is dominant in the preparation process; while if the molecular weight of the porogen is higher (PEG1000, PEG2000), new pores are formed and/or pores are enlarged.

Creative Commons License Content from this work may be used under the terms of the Creative Commons Attribution 4.0 license. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.


  1. 1 L. Yao, L. Zhang, R. Wang, S. Chou, and Z. L. Dong, J. Hazardous Mater. 301, 462 (2016).
  2. 2 T. Tsuru, M. Miyawaki, T. Yoshioka, and M. Asaeda, AIChE J. 52, 522 (2006).
  3. 3 W. R. Bowen, A. W. Mohammad, and N. Hilal, J. Membrane Sci. 126, 91 (1997).
  4. 4 Z. Chen, K. Ito, H. Yanagishita, N. Oshima, R. Suzuki, and Y. Kobayashi, J. Phys. Chem. C 115, 18055 (2011).
  5. 5 K. Ito, Z. Chen, W. Zhou, N. Oshima, H. Yanagishita, R. Suzuki, and Y. Kobayashi, Kobunshi Ronbunshu 69, 443 (2012).
  6. 6 Z. Chen, C. Yin, S. Wang, Q. M. Fu, D. R. Deng, Z. D. Lin, P. Fu, Y. Zhang, J. Y. Wu, and P. F. Fang, Polym. Adv. Technol. 27, 1446 (2016).
  7. 7 P. Winberg, M. Eldrup, N. J. Pedersen, M. A. van Es, and F. H. J. Maurer, Polymer 46, 8239 (2005).