Liquid Crystals of Dendron-like Pt Complexes Processable into Nanofilms

Abstract

A series of (cholesteryl) 2,5-dibromobenzoate dendrons consisting of a first generation (G1=1 (cholesteryl) 4-benzoate), second generation (G2=2 (cholesteryl)s 4-benzoates) and third eneration (G3=4 (cholesteryl)s 4-benzoates) were synthesized step-by-step by the convergence approach. The 2,5-dibromo G1, G2 and G3 synthesized dendrons were subjected to co-polymerization with (butyl) 2,5-diethynyl benzoate by the Sonogashira cross-coupling reaction to afford rigid rod-like vermicular dendrimers of the phenyleneethynylene type, which resulted be very soluble in non-polar solvents such as CHCl3, THF, toluene. Their chemical structures were analyzed by 1H, APT, DEPT-135, 13C NMR, however for their correct proton-carbon assignation, it was necessary to carry out 2D-HETCOR correlations. The thermal properties studied by DSC, TGA and Polarized light microscopy showed that all of the (cholesteryl) 2,5-dibromobenzoate dendrons exhibited a mesomorphic behavior: Crystal (double arrow) Smectic C (or Nematic) (double arrow) Isotropic transitions, where mesophases are presented in a very short temperature range. In what concerns to the copolymers, in spite of that they do not exhibit any know texture reported in the literature, however they seem to exhibit Smectic C and/or Nematic mesophases, nonetheless the study of X-ray at small angle is necessary in order to better determine their real supramolecular order of the mesophase(s).

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Document Details

Document Type
Technical Report
Publication Date
May 01, 2013
Accession Number
ADA590637

Entities

People

  • Eduardo Arias
  • Ivana Moggio
  • Ronald F. Ziolo

Tags

Communities of Interest

  • Advanced Electronics
  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Advanced Materials
  • Air Force
  • Air Force Research Laboratories
  • Benzoates
  • Chemistry
  • Confocal Microscopy
  • Crystals
  • Films
  • Liquid Crystals
  • Manufacturing
  • Microscopy
  • Optical Properties
  • Polymers
  • Thin Films
  • Transition Temperature
  • Transitions
  • X Rays

Fields of Study

  • Chemistry

Readers

  • Electrochemical Surface Science
  • Polymer Science and Technology

Technology Areas

  • Microelectronics