The glass transition and melting temperatures of binary random copolymers are mostly observed as nearly the average of each homopolymer with moderate deviations. However, copolymerization of binary monomers of liquid crystalline (LC) side chains often leads to significant deviations of phase transition temperatures due to a cooperative molecular assembly effect. In this work, a systematic exploration of random copolymer systems composed of side chain mesogens of cyanobiphenyl (CB) and azobenzene (Az) has been made. Each homopolymer exhibits a smectic A phase; however, the copolymerization of CB and Az methacrylate monomers having a similarly long methylene spacer length leads to induction of higher ordered smectic phases such as smectic B (hexatic packing with free mesogen rotation) and even smectic E (herringbone packing with restricted mesogen rotation) with significant enhancements of the isotropization temperature (clearing point). This effect diminishes when the spacer length of the two mesogens differs significantly. The copolymerization ratio of 2:1 (CB:Az) most efficiently induces the SmE phase, indicative of a stoichiometric supramolecular nature. The knowledge obtained here should be of great help in tailoring the thermal and structural properties of LC polymer materials.

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