Characterization of open-cell sponges via magnetic resonance and X-ray tomography

Research output: Contribution to journalArticlepeer-review


  • Abhishek Shastry
  • Matthieu N. Boone
  • Veerle Cnudde
  • Karl Braeckman
  • Anju D. M. Brooker
  • Eric S. J. Robles

Colleges, School and Institutes

External organisations

  • Ghent University
  • Procter & Gamble Brussels Innovation Center
  • Procter & Gamble Company, Newcastle Innovation Center


The applications of polymeric sponges are varied, ranging from cleaning and filtration to medical applications. The specific properties of polymeric foams, such as pore size and connectivity, are dependent on their constituent materials and production methods. Nuclear magnetic resonance imaging (MRI) and X-ray micro-computed tomography (µCT) offer complementary information about the structure and properties of porous media. In this study, we employed MRI, in combination with µCT, to characterize the structure of polymeric open-cell foam, and to determine how it changes upon compression, µCT was used to identify the morphology of the pores within sponge plugs, extracted from polyurethane open-cell sponges. MRI T 2 relaxation maps and bulk T 2 relaxation times measurements were performed for 7 dH water contained within the same polyurethane foams used for µCT. Magnetic resonance and µCT measurements were conducted on both uncompressed and 60% compressed sponge plugs. Compression was achieved using a graduated sample holder with plunger. A relationship between the average T 2 relaxation time and maximum opening was observed, where smaller maximum openings were found to have a shorter T 2 relaxation times. It was also found that upon compression, the average maximum opening of pores decreased. Average pore size ranges of 375–632 ± 1 µm, for uncompressed plugs, and 301–473 ± 1 µm, for compressed plugs, were observed. By determining maximum opening values and T 2 relaxation times, it was observed that the pore structure varies between sponges within the same production batch, as well as even with a single sponge.

Bibliographic note

Funding information: This research was funded by European Union’s Horizon 2020 research and innovation programme for funding under grant No. 722871 in the scope of the Marie Sklodowska-Curie action ITN BioClean. The Ghent University Special Research Fund (BOF-UGent) is acknowledged for the financial support to the Centre of Expertise UGCT (BOF.EXP.2017.007). The authors also thank the University of Birmingham and the UK Engineering and Physical Science Research Council (EPSRC grant EP/K039245/1) for financial support.


Original languageEnglish
Article number2187
Issue number9
Publication statusPublished - 24 Apr 2021


  • Cleaning, MRI, Maximum opening, Open-cell foam, Polyurethane, Pore size, T relaxation, µCT, cleaning, pore size, T2 relaxation, maximum opening, polyurethane, open-cell foam