Refractometric discrimination of void-space filling and swellingduring vapour sorption in polymer films

Cross, G.H.; Ren, Y.T.; Swann, M.J.

doi:10.1039/b007847f

Refractometric discrimination of void-space filling and swellingduring vapour sorption in polymer films

Cross, G.H.; Ren, Y.T.; Swann, M.J.

Authors

G.H. Cross

Y.T. Ren

M.J. Swann

Abstract

Thin polymeric films have been deposited as upper cladding layers on a new integrated optical interferometer fabricated from layers of silicon oxynitride on a silicon wafer. The evanescent field of the probing waveguide mode transduces refractive index changes in the polymer layer into the measured phase changes in the device. Real-time measurement of index change and its sign is obtained. Upon exposure to humid air, we record water sorption by films of poly(vinyl pyrollidone) by a rapid positive index change for void-space filling followed by a slow negative index change for swelling. Sorption of water vapor into a thin film of the viscous liquid polymer polyethylenimine shows only swelling mode behaviour and a simple constitutive model can be applied to give the fractional water occupied volume.

Citation

Cross, G., Ren, Y., & Swann, M. (2000). Refractometric discrimination of void-space filling and swellingduring vapour sorption in polymer films. Analyst, 125(12), 2173-2175. https://doi.org/10.1039/b007847f

Journal Article Type	Article
Publication Date	Jan 1, 2000
Deposit Date	May 8, 2013
Journal	Analyst
Print ISSN	0003-2654
Publisher	Royal Society of Chemistry
Peer Reviewed	Peer Reviewed
Volume	125
Issue	12
Pages	2173-2175
DOI	https://doi.org/10.1039/b007847f