Rigid rod polymers
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- In addition to new derivatives from the PBZX family and novel rigid-rod polymers such as rigid-rod polyimides and aromatic poly(pyridinium salt), there are several special groups of rigid-rod polymers that have been studied and developed rapidly after the 1980s.
- Among them are polyphenylenes, poly(phenylene ethynylene), poly(p-phenylenevinylene) (qv), polythiophenes, Rigid rod polymerss, polyquinolines, and some organometallic polymers .
- Rigid rod-like polymers form a nematic phase which is of the tumbling type at small and moderate shear rates, to become flow-aligning at high shear rates as a result of nonlinearity.
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