A series of novel ordered poly(ester-imide)s were synthesized using both solution and melt polymerization techniques and their liquid crystal properties studied. Commercially available 6-aminohexanoic acid and 11-aminoundecanoic acid were reacted with 1,2,4,5-benzenetetracarboxylic anhydride (PMDA) by a melt reactions to give -pyromellitimide dicarboxylic acid derivatives. These derivatives were treated with thionyl chloride to give -pyromellitimide dicarboxylic dichloride derivatives which were reacted with a series of diols having six, eight, nine, ten and twelve methylene units in their structural units by a solution polymerization technique, using refluxing 1,2,4-trichlorobenzene as solvent. These same diols were treated with acetic anhydride to produce a series of diacetates. Using a melt polymerization technique, the diacetates were treated with -pyromellitimide dicarboxylic acids to give the same series of poly(ester-imide)s as prepared by the solution method. The polymers obtained were characterized using infrared spectroscopy (IR), differential scanning calorimetry (DSC), polarizing light microscopy (PLM) and dilute solution viscosity. Inherent viscosities of the prepared polymers ranged from 0.07 to 0.25 dL/gram for solution polymerization and from 0.67 to 1.00 dL/gram for melt polymerization. Phase transition temperatures, determined by differential scanning calorimetry, ranged from 67 to 140C for solution polymerization; from 129 to 232C for melt polymerization. Solution and melt polymerization poly(ester-imide)s showed nematic and smectic liquid crystal bifringence textures using a hot stage under polarizing light microscopy.
Library of Congress Subject Headings
Polymer liquid crystals; Polyesters; Polymer melting; Polymer solutions
Department, Program, or Center
School of Chemistry and Materials Science (COS)
Nie, Fei, "Synthesis and characterization of poly(ester-imide)s" (1989). Thesis. Rochester Institute of Technology. Accessed from
RIT – Main Campus
Note: imported from RIT’s Digital Media Library running on DSpace to RIT Scholar Works. Physical copy available through RIT's The Wallace Library at: QD923 .N54 1989