Étude de l'orientation des polymères cristallins liquides supramoléculaires à chaînes latérales

This study investigated the unique light-induced orientation behavior of a supramolecular side-chain liquid crystalline polymer by comparing it with the covalent counterpart. The results showed it has a potential utility in holographie storage and other photonic applications. An amorphous azopyridine-containing polymer was synthesized. And its supramolecular side-chain liquid crystalline complexes with hexanoic acid and decanoic acid were obtained respectively. Characterizations confirming the hydrogen bonds and the consequential liquid crystalline phases were performed. Comparing with a covalent azobenzene-containing side-chain liquid crystalline polymer counterpart, the photoinduced isomerization, orientation and anneal effects of the samples were studied. Two supramolecular samples have more data scattering in the photoinduced isomerization kinetic study comparing to the covalent sample. The complex of azopyridine polymer with hexanoic acid (Hex) has a similar behavior as the covalent azobenzene liquid crystalline polymer (Ref) in isomerization, orientation and annealing results. The complex of azopyridine polymer with decanoic acid (De) has a much different behavior. We infer that it is caused by the"liquid crystalline cooperative motion". As a secondary aim of this study, the advantage and weakness of four different excitation methods to induce orientation have been compared