Synthesis and characterization of hyperbranched aromatic polyesters used for polymeric graded‐index materials

Abstract

A series of hyperbranched aromatic polyesters, with different numbers of terminal naphthyl groups per molecule, were synthesized from 5‐hydroxyisophthalic acid as an AB2 type monomer and ethylenediaminetetraacetic acid as an ‘initiator core’ molecule via an ‘one‐step’ approach, to be modified with β‐naphthol. These polyesters had polydispersities in the range 1.78–2.13, indicated by gel permeation chromatography, and degrees of branching between 0.45 and 0.60 by 1H NMR using model compounds. Characterization indicated intense absorption bands in the near‐UV spectral region and one fluorescence centre with emission at 365 nm. The refractive index increased with the number of naphthyl groups up to a value of 1.6205. The diffraction efficiency was about 8.7% for diffraction grating of cured films. Copyright © 2003 Society of Chemical Industry

Dendritic polyisophthalate endcapped with naphthyl groups for holographic recording

“…BTCTC was synthesized by reacting 1,3,5-benzentricarboxylic acid with thionyl chloride in dichloromethane. 16 1,3,5-benzentricarboxylic acid, 5-hydroxyisophthalic acid (HIPA) and dimethylaminopyridine (DMAP) were supplied from Aldrich, Germany. b-Naphthol was supplied from Ting-Xin Chemical Co., Shanghai, China.…”

Preparation and thermal stability of new cellulose‐based poly(propylene imine) and poly(amido amine) hyperbranched derivatives

“…The unusual properties of these materials result from their highly branched structure, generally globular shape, multiplicity of chain ends, controlled molecular weight, versatility in modification of terminal groups, and capability of intermolecular interaction with the immediate environment. These highly functionalized branched materials have found use in many applications 25–30. Poly(amido amine)31 (PAMAM) and poly(propylene imine)32 (PPI) dendrimers are of the first complete dendrimers synthesized, well characterized and commercialized.…”