Abstract
A new class of thermotropic liquid crystalline polymers and cyclic trimers has been prepared by the linkage of aromatic azo mesogenic units to the phosphorus atoms of cyclic and polymeric phosphazenes through flexible oligomeric ethyleneoxy spacer units. The single-substituent polymers, of formula [NP{0-(CH2CH2O)mC6H4N=NCeH4OCH3)2]n where m = 2 or 3, showed thermotropic liquid crystallinity. The cyclic trimer, [NP{O(CH2CH2O)2C6H4NNC6H4OCH3)2]3, showed typical nematic schlieren texture between 192 and 166 °C on the cooling cycle (monotropic). The influence of a terminal para substituent on the mesogen, the length of the spacer unit, and the cyclic or long-chain polymeric character of the phosphazene on the liquid crystallinity were investigated.
Original language | English (US) |
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Pages (from-to) | 2596-2602 |
Number of pages | 7 |
Journal | Macromolecules |
Volume | 22 |
Issue number | 6 |
DOIs | |
State | Published - Nov 1 1989 |
All Science Journal Classification (ASJC) codes
- Organic Chemistry
- Polymers and Plastics
- Inorganic Chemistry
- Materials Chemistry