2011/04/20 by Simon Gruener, Patrick Huber
Materials Science · Physics and Astronomy · #Glass properties and applications #Material Dynamics and Properties #Mesoporous Materials and Catalysis #cond-mat.mes-hall #cond-mat.mtrl-sci #cond-mat.soft #physics.chem-ph #physics.flu-dyn
paper · pdf · doi:10.1088/0953-8984/23/18/184109
published as J. Phys.: Condens. Matter 23, 184109 (2011) · 18 pages, 8 figures
openalex publication_date 2011/04/20 · arxiv created 2011/05/12 · arxiv updated 2011/05/13 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/30
We present, along with some fundamental concepts regarding imbibition of liquids in porous hosts, an experimental, gravimetric study on the capillarity-driven invasion dynamics of water and of the rod-like liquid crystal octyloxycyanobiphenyl (8OCB) in networks of pores a few nanometers across in monolithic silica glass (Vycor). We observe, in agreement with theoretical predictions, square root of time invasion dynamics and a sticky velocity boundary condition for both liquids investigated. Temperature-dependent spontaneous imbibition experiments on 8OCB reveal the existence of a paranematic phase due to the molecular alignment induced by the pore walls even at temperatures well beyond the clearing point. The ever present velocity gradient in the pores is likely to further enhance this ordering phenomenon and prevent any layering in molecular stacks, eventually resulting in a suppression of the smectic phase in favor of the nematic phase.