Morphology and size control of inorganic particles in polyimide hybrids by using SiO2–TiO2 mixed oxide

A series of novel metal-containing aromatic polyimides were synthesized from divalent metal oxide/hydroxide (MO/M(OH)2) (M = Ba, Sr, Ca, Mg, Zn, Cd, Co, Ni, Pb, Cu), p-aniline sulfonic acid (ASA), and 3,3′-4,4′-benzophenonetetracarboxylic dianhydride (BTDA). The C, H, N, and S contents were determined by elemental analysis, their structures were characterized by proton nuclear magnetic resonance (1H-NMR) and Fourier transform infrared (FT-IR) spectroscopy, and the thermal properties of the polymers were also studied by TG–DTA. It is found that metal-containing polyimides have a higher thermal stability. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 2363–2369, 2000

Preparation and characterization of metal-containing aromatic polyimides

N,N′-(4,4′-carbonyl-diphthaloyl)-bis-(L-phenylalanine)diol (p4) as novel chiral diol was prepared from L-phenylalaninol (2) and 4,4′-carbonyldiphthalic dianhydride (3) in dry acetic acid under refluxing conditions in high yield and characterized with Fourier transform infrared (FTIR), 1H-NMR and 13C-NMR. The step-growth polymerization of this novel chiral diol (p4) containing an imide group and a chiral group with different diisocyanates in dry N-methylpyrrolidinone (NMP) was conducted under conventional heating conditions. The resulting new optically active polymers were obtained in good yields and their inherent viscosities ranged between 0.18 and 0.29 dL g—1. The polymers were characterized with FTIR, 1H-NMR, differential scanning calorimetry and thermogravimetric analysis. These polymers are soluble in aprotic-polar solvents such as N,N-dimethylacetamide, NMP, N,N-dimethylformamide, dimethyl sulfoxide and sulfuric acid. Thermogravimetric analysis showed that the 10% weight loss temperature under air a...

Synthesis and Characterization of Novel Chiral Poly(imide-urethane) Derived from N,N′-(4,4′-carbonyl-diphthaloyl)-bis-(L-phenylalanine)diol with Different Diisocyanates

NMR spectroscopy, and in particular solid-state nuclear magnetic resonance (NMR), has an important role to play in the determination of structure, conformation, morphology, and molecular motion in poly(imide) materials. This chapter discusses the various classes of poly(imide)s and reviews the current literature on NMR of these materials. Infra red (IR) spectroscopy has often been used to study the conversion of amic acids to imides. Despite the popularity of this technique, important questions have been raised concerning the quantitative aspects of the results, especially at high conversion. NMR spectroscopy, in particular solution-state NMR, has the advantage of greater chemical information, and when care is taken, provides quantitative measurements of the extent of conversion of amic acid to imide. For many complex poly(imide) mixtures, the NMR spectra are severely overlapped, due to the structural similarity of many of the monomer repeat units and also the presence of a range of conformations frozen-in in the solid state. The use of isotopic enrichment of selected sites, with 15 N or 13 C nuclei, can alleviate this problem. However, such a course of action is tedious and expensive. An alternate method for improving resolution in the cross polarization and magic angle spinning (CPMAS) spectra is to measure the spectra above the glass-transition temperature of the materials, thus allowing averaging of conformations frozen in the glassy state.

Chapter 13 Poly(imide)s

Two kinds of soluble polyimides from pyromellitic dianhydride with Congo red and 4-sulfanilamide were prepared, respectively. Their structures were characterized by IR and 1H-NMR, and the thermal properties were investigated by DSC and TG–DTA. © 1995 John Wiley & Sons, Inc.

Jinsong Liu

Papers

Preparation and characterization of soluble polyimides

A solid-state 13C n.m.r. spectroscopic study of metal-containing polyimides