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Highly crosslinked networks were produced through a series of diacids and tetrakis pyridyls. These materials displayed complex crystallization behaviors over multiple heat/cool cycles. The shifting of crystallization behaviors with time in the melt phase seems to indicate that the materials move toward thermodynamically ideal structures. This behavior is suggestive of a type of memory in which the networks remember the morphological structure previous to the melt and improve upon that structure in the next cooling cycle. The network/memory phenomena observed in small molecule diacid/tetrapyridyl systems also appeared to exist when poly(ethylene terephthalate) (PET) polymer was used as the source of carboxylic acid functionalities. The same time-dependent behaviors, suggestive of sequential steps toward thermodynamically optimum states, were observed when the PET/tetrapyridyl systems were thermally cycled. It was also observed that complexation of tetrapyridyl with PET brought about a significant change in oxygen gas barrier properties; these changes were opposite to those obtained when covalent crosslinks were introduced into PET.

A series of supramolecular polymers and networks with variable liquid crystalline characteristics have been created. These species are formed though the benzoic acid/pyridine associations of a flexible bisacid and a mixture of a rigid bispyridyl and a non-mesogenic tetrapyridyl. The networked systems displayed liquid crystalline characteristics up to and including 22.5% netpoint inclusion. Above this concentration, only crystalline and melting behaviours were observed. This observed phenomenon would seem to be linked to the statistical correlation of hydrogen bond acceptors and donors. There was also no observed phase segregation of the species after multiple heat/cool cycles and extended periods of time in the isotropic state. This would indicate that the thermodynamically more stable mesogenic phase cannot out-compete the non-liquid crystalline network. Computational analysis indicates no significant difference in hydrogen bond strength between the two different hydrogen bond acceptors.

A series of main chain liquid crystalline polymers were formed through intermolecular hydrogen bonding between a functionalized bisazopyridine phenol and aromatic bisacids. The behaviour of these complexes was studied through differential scanning calorimetry and thermal polarizing optical microscopy. The presence of the hydrogen bonds was confirmed through infrared spectroscopy. These complexes formed thermotropic mesophases. The phases were determined to be nematic in nature from the schlieren textures of the optical micrographs. As the length of flexible spacer groups separating the mesogenic portions increased, the clearing temperatures of the mesophases decreased. As the length of the rigid component increased, the clearing temperature increased. A new bisacid species based on 2-hydroxy-6-naphthoic acid was used to increase clearing temperatures while remaining within an acceptable temperature window.