Accession Number:

ADA207413

Title:

Polyisoimide for In-Situ Rigid-Rod Molecular Composite Applications

Descriptive Note:

Interim rept. Dec 1986-Sep 1987

Corporate Author:

DAYTON UNIV OH RESEARCH INST

Report Date:

1989-03-01

Pagination or Media Count:

32.0

Abstract:

A new material concept using in-situ rod formation from a coil like polytetramethyl isoimide was explored for rigid rod molecular composite applications. Its feasibility relies mainly on an adequate degree of isomerization leading to a rod like polyimide of sufficient length for reinforcing the composite. Isomerization induced thermally was demonstrated in solutions and in the solid state with visible-light and infrared spectroscopies. X ray scattering revealed that the polyisoimide was amorphouse while the polyimide was highly crystalline. However, gel permeation chromatography showed a low degree of isomerization and possible polymer degradation. This was further supported by the absence of birefringence and anisotropy in light scattering from the converted polyimide. Computations on related dimers indicated that a high degree of isomerization was unlikely due to polysoimide conformational restriction. Attempts to fabricate molecular composites utilizing this concept did not result in rigid-rod reinforcement from the polyimide. Keywords Thermal isomerization Polyisoimide Polyimide Molecular composite Infrared spectroscopy Gel permeation chromatography X ray scattering Molecular modeling.

Subject Categories:

  • Organic Chemistry
  • Polymer Chemistry

Distribution Statement:

APPROVED FOR PUBLIC RELEASE