We have synthesized new liquid crystal polymers containing paramagnetic organometallic structural units. The paramagnetic organometallic units are tetradentate Schiff base complexes of copper (II) containing N,N prime -bis(salicylidene)ethylenediimine. The diamagnetic segments are polyesters containing random sequences of the structural units, dioxyphenyl, pimeloate, and oxybenzoate. Microscopic observations on these polymers reveal the formation of liquid crystalline melts above 136 degree C with fairly uniform molecular alignment. Also, DSC and x-ray measurements indicate a high degree of order in the fluid and relatively high crystallinity in the solid state. Interestingly, we found that in a magnetic field the interaction of the paramagnetic unit partially rotates the director of diamagnetic segments away from their 'usual' alignment parallel to the field. These experiments probe intramolecular cooperativity and also suggest possibilities on the use of molecular paramagnets to control microstructural orientation in materials from liquid crystal polymers.
|Title of host publication||Polymeric Materials Science and Engineering, Proceedings of the ACS Division of Polymeric Material|
|Number of pages||1|
|Publication status||Published - 1987|
ASJC Scopus subject areas
- Chemical Engineering (miscellaneous)
- Polymers and Plastics