Abstract
In this paper we deal with a cellulose derivative cholesteric dispersed liquid crystal (CCDLC) with mechanically tuneable optical properties. The composite is formed with a matrix of acetoxypropylcellulose with embedded micrometric and submicrometric droplets of a cholesteric mixture. Polarizing optical microscopy and atomic force microscopy (AFM) measurements performed on the system are reported and it is shown that the wavelength of the reflected light can be changed by a temperature variation and it is also changeable through a mechanical deformation. The pitch of the deformed droplets can be measured from AFM photographs and compared with the wavelength reflected by the CCDLC composite material.
Acknowledgements
This work was supported by projects POCTI/CTM/56382/2004 and POCTI/CTM/37435/2002, and by the Portuguese Science Foundation (FCT) through Pluriannual contracts with CENIMAT and CFMC/UL.