Alignment of nematic liquid crystals on an electrically poled photopolymerfilm

We have observed liquid crystal alignment on an electrically poled polyviny lcinnamate film in which a polar symmetry was introduced by an in-plane ele ctric field and stabilized by unpolarized ultraviolet light. The azimuthal anchoring energy and pretilt angle was measured in a twisted nematic or pla nar cell and is explained via the molecular structure of the unreacted cinn amates and of the photoproducts beta -truxinates. Cinnamates mainly contrib ute via a strong flow alignment, while beta -truxinate produces the anisotr opic properties of the film such as its polar anisotropy, azimuthal anchori ng, and pretilt angle. (C) 2001 American Institute of Physics.