Synthesis and Characterization of photoconductive properties of 2-alkylphenyl-6-alkylnaphthalene derivatives. (2)

Abstract

We have synthesized several liquid crystalline 2-(4'-alkyl phenyl)-6-alkyl naphthalene derivatives and characterized their phase transition behaviors and photoconductive properties. These materials exhibited SmA, SmB and SmE phases, which is same as 6-alkoxy naphthalene analogues, but their liquid crystalline temperature ranges were fairly lower. Especially 2-(4'-octyl-phenyl)-6-butyl- naphthalene (8-PNP-4) exhibited liquid crystalline phase under room temperature. Electronic transport of positive carriers was observed and their mobility was on the order of 10^-2cm²/Vs(in the SmE). This was the same result with that of 6-alkoxy naphthalene analogues and indicates that molecular order in smectic layer plays a dominant role on the carrier transport, as far as the core moiety is same.