Supramolecular main-chain liquid crystalline polymers with competitive hydrogen bonding: Inclusion of structurally analogous hydrogen bond acceptors and the effects on liquid crystallinity

ABSTRACT

A series of liquid crystalline supramolecular copolymers formed through hydrogen bonding has been created. These polymers composed of bis-benzoic acids and two of pyridyl species- a small rigid bispyridyl capable of forming a mesophase and a small, flexible bis pyridyl non-mesogenic disruptor species. It was found that the polymers display monotropic nematic character at high concentrations of disruptors – up to 75% inclusion. Smectic phases were observed in loadings up to 50%. It is believed that the structural similarities between the mesogenic and non- mesogenic acceptors contributes significantly to the enhanced stability of the liquid crystalline phases at high composition.

KEYWORDS:

• Hydrogen bonding
• liquid crystal
• nematic
• smectic
• mesogen

Funding

The authors would like to thank The National Science Foundation (Award Number 1410082), The Camille and Henry Dreyfus Foundation and The Office of Research and Sponsored Programs at the University of Wisconsin-Eau Claire for their financial support of this work.