Accession Number:

ADA282381

Title:

Novel Thermooxidatively Stable Poly(ether-imide-benzoxazole) and Poly (ester-imide-benzoxazole)

Descriptive Note:

Technical rept. 1 Jun 1993-31 May 1994

Corporate Author:

UNIVERSITY OF SOUTHERN MISSISSIPPI HATTIESBURG DEPT OF POLYMER SCIENCE

Personal Author(s):

Report Date:

1994-07-15

Pagination or Media Count:

53.0

Abstract:

4-Hydroxy-5-nitrophthalimides were produced via nucleophilic aromatic substitution NAS of 4,5-dichloro phthalimide substituents by potassium nitrite. The use of a N-phenylphthalimide having a protected 4-hydroxyl group allows concurrent deprotection and nitro reduction to amine to give the 4- hydroxy-5-amino-N-4 hydroxyphenyl phthalimide. This key intermediate Is the precursor to a polyether-imide-benzoxazole, and is the condensable monomer for a polyester-imide-benzoxazole. Benzoxazole monomer formation via condensation with p-fluorobenzoyl chloride afforded 2-4-fluorophenyl-5,6,-N-4- hydroxyphenylimidebenzoxazole, which was polymerized under NAS conditions to produce a polyether-imide-benzoxazole having an endothermic transition at 454 deg C with weight retention of 90 at 500 deg C in both air and nitrogen. Solution polycondensation of the 4-hydroxy-5-amino-N-4-hydroxyphenyl phthalimide monomer with isophthaloyl chloride afforded a polyesteramide- imide which was isolated and thermally cyclodehydrated in the solid state under vacuum to give a polyester-imide-benzoxazole having 95 weight retention at 500 deg C in both air and nitrogen, with no detectable DSC transitions up to 500 deg C.

Subject Categories:

  • Organic Chemistry
  • Physical Chemistry
  • Polymer Chemistry
  • Thermodynamics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE