PMID- 20848011
OWN - NLM
STAT- PubMed-not-MEDLINE
DCOM- 20101210
LR  - 20101013
IS  - 1473-0197 (Print)
IS  - 1473-0189 (Linking)
VI  - 10
IP  - 21
DP  - 2010 Nov 7
TI  - Microchannel deformations due to solvent-induced PDMS swelling.
PG  - 2972-8
LID - 10.1039/c003504a [doi]
AB  - The compatibility of polydimethylsiloxane (PDMS) channels with certain solvents 
      is a well known problem of soft lithography techniques, in particular when it 
      leads to the swelling of the PDMS blocks. However, little is known about the 
      modification of microchannel geometries when they are subjected to swelling 
      solvents. Here, we experimentally measure the deformations of the roof of PDMS 
      microchannels due to such solvents. The dynamics of impregnation of the solvents 
      in PDMS and its relation to volume dilation are first addressed in a model 
      experiment, allowing the precise measurement of the diffusion coefficients of 
      oils in PDMS. When Hexadecane, a swelling solvent, fills a microchannel 1 mm in 
      width and 50 mum in height, we measure that the channel roof bends inwards and 
      takes a parabolic shape with a maximum deformation of 7 mum. The amplitude of the 
      subsidence is found to increase with the channel width, reaching 28 mum for a 2 mm 
      wide test section. On the other hand, perfluorinated oils do not swell the PDMS 
      and the microchannel geometry is not affected by the presence of 
      perfluorodecalin. Finally, we observe that the trajectories of droplets flowing 
      in this microchannel are strongly affected by the deformations: drops carried by 
      swelling oils are pushed towards the edges of the channel while those carried by 
      non-swelling oils remain in the channel center.
FAU - Dangla, Remi
AU  - Dangla R
AD  - LadHyX and Department of Mechanics, Ecole Polytechnique, CNRS, 91128 Palaiseau 
      Cedex, France.
FAU - Gallaire, Francois
AU  - Gallaire F
FAU - Baroud, Charles N
AU  - Baroud CN
LA  - eng
PT  - Journal Article
DEP - 20100916
PL  - England
TA  - Lab Chip
JT  - Lab on a chip
JID - 101128948
EDAT- 2010/09/18 06:00
MHDA- 2010/09/18 06:01
CRDT- 2010/09/18 06:00
PHST- 2010/09/18 06:00 [entrez]
PHST- 2010/09/18 06:00 [pubmed]
PHST- 2010/09/18 06:01 [medline]
AID - 10.1039/c003504a [doi]
PST - ppublish
SO  - Lab Chip. 2010 Nov 7;10(21):2972-8. doi: 10.1039/c003504a. Epub 2010 Sep 16.