Synthesis and mesomorphic properties of fishbonelike, liquid crystalline polysilsesquioxanes: 4. Pd‐coordinating, fishbone‐like imine‐based liquid crystalline polysilsesquioxane

摘要

AbstractA new type of Pd‐coordinating, imine‐based, fishbone‐like liquid crystalline polysilsesquioxanes (Pd‐FBI) including μ‐acetato‐bridged Pd‐FBI Pd(μ‐oAc)‐FBI and μ‐chloro‐bridged Pd‐FBI Pd(μ‐Cl)‐FBIhas been synthesized first by a hydrosilylation reaction to form fishbone‐like, imine‐based liquid crystalline polysilsesquioxane (H‐FBI and MH‐FBI respectively,) and then by an ortho‐palladation reaction with palladium acetates to obtain Pd(μ‐oAc)‐FBI. The latter was further subjected to ligand substitution reaction with NaCl to form Pd(μ‐Cl)‐FBI. Their mesomorphic properties investigated by differential scanning calorimetry (DSC) and optical polarization microscopy (OPM). show that the Pd‐FBI is a thermotropic liquid crystalline polymer and its clearing temperatures and mesophase range are much higher than those of the corresponding comb‐like imine liquid crystalline polysiloxanes (IMLCP) by about 100 °C. In this paper the influence of