Ferroelectric liquid crystals for second order nonlinear opitcs: Synthesis of an azo bridged dimer ferroelectric liquid crystal side-chain polymer with a poly(methylsiloxane) backbone

POLY 153

Yongqiang Zhang, zhang@displaytech.com and Michael J. O'Callaghan. Displaytech, Inc, 2602 Clover Basin Drive, Longmont, CO 80503
Side-by-side dimer ferroelectric liquid crystal (FLC) mesogens, in which two conventional rod-shaped FLCs are connected together by a lateral conjugated bridge between their cores, are promising candidates for NLO applications since their specific molecular structure allows for incorporation of strong chromophores along the polar axis of FLCs. Diazo bridge is usually employed owing to its excellent conjugation capability and easy construction. An azo bridged dimer 1, which contains a strong donor (diethylamino) and a strong acceptor (nitro), was efficiently synthesized by the employment of diazo coupling reactions and sequential esterfications with different acid chlorides. 1 exhibited a thermodynamically stable enantiotropic SmC* phase. In order to stabilize the dimer mesogen, a side-chain polymer 2 with a poly(methylsiloxane) backbone was synthesized by hydrosilylation of 1 with poly(methylhydrosiloxane) in the present of Karstedt's catalyst. The 1H NMR spectrum of 2 indicated that all silicon-hydrogen bonds in poly(methylhydrosiloxane) was completely reacted with 1.
 

General Papers: Synthesis and Characterization
6:00 PM-8:00 PM, Sunday, 10 September 2006 Moscone Center -- Hall D, Poster

Sci-Mix
8:00 PM-10:00 PM, Monday, 11 September 2006 Moscone Center -- Hall D, Sci-Mix

Division of Polymer Chemistry

The 232nd ACS National Meeting, San Francisco, CA, September 10-14, 2006