WETTING OF POLYMER BRUSHES BY A NEMATOGENIC COMPOUND

The spreading of nematic liquid crystal (LC) droplets on polymer brush es has been characterized by optical microscopy and ellipsometry. We o bserved a first thin precursor film made of pure LC on top of the dry brush which grows with time according to a hypodiffusive law. The pene tration of the brush by the LC is then observed. With a thick enough l ayer, the molecules diffusing into the brush swell it so that a should er appears at the edge of the droplet. The evolution of that shoulder is self-similar, confirming that the later process is diffusive.