Eur. Phys. J. E (2013) 36: 28
https://doi.org/10.1140/epje/i2013-13028-9

Regular Article

Eliminating cracking during drying

¹²⁸ Department of Physics, The Chinese University of Hong Kong, Hong Kong, China
²²⁸ The School of Physics and Astronomy, University of Edinburgh, Edinburgh, UK

^* e-mail: xulei@phy.cuhk.edu.hk

Received: 13 December 2012
Revised: 2 March 2013
Accepted: 6 March 2013
Published online: 22 March 2013

Abstract

When colloidal suspensions dry, stresses build up and cracks often occur -a phenomenon undesirable for important industries such as paint and ceramics. We demonstrate an effective method which can completely eliminate cracking during drying: by adding emulsion droplets into colloidal suspensions, we can systematically decrease the amount of cracking, and eliminate it completely above a critical droplet concentration. Since the emulsion droplets eventually also evaporate, our technique achieves an effective function while making little changes to the component of final product, and may therefore serve as a promising approach for cracking elimination. Furthermore, adding droplets also varies the speed of air invasion and provides a powerful method to adjust drying rate. With the effective control over cracking and drying rate, our study may find important applications in many drying- and cracking-related industrial processes.