We report on the synthesis and the properties of side-chain liquid-crystal
polymer (LCP) brushes attached to silicon oxide surfaces. The polymer monol
ayers have been generated at the surface of the substrate in situ following
a "grafting-from" procedure. The mesogenic group of the LC brushes consist
s of a phenylbenzoate moiety linked to the methacrylate main chain via a fl
exible spacer. The thickness of the brush and the grafting density of the s
urface-attached polymer molecules can be controlled by adjusting the monome
r concentration during brush growth and the reaction time of the polymeriza
tion, respectively. LC brushes with a thickness of up to 200 nm in the dry,
solvent-free state have been obtained. The transition temperatures between
the nematic and the isotropic state have been studied and compared to thos
e of spin-cast films of the same polymer. The optical textures are investig
ated as a function of layer thickness, temperature, and sample history. The
textures exhibit a strong memory effect in the sense that the exact same t
exture reappears after isotropization by heating or solvent exposure and re
turning to the nematic state.