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.
Descriptors:
- *POLYMERS
- *BENZOXAZOLES
- *ETHERS
- *ESTERS
- *IMIDES
- THERMAL PROPERTIES
- STABILITY
- AIR
- PRECURSORS
- VACUUM
- SOLIDS
- NITROGEN
- REDUCTION
- AMINES
- OXIDATION
- FLUORINE
- WEIGHT
- CHLORIDES
- MONOMERS
- TRANSITIONS
- AROMATIC COMPOUNDS
- AMIDES
- PHENYL RADICALS
- SOLID STATE CHEMISTRY
- POTASSIUM
- HYDROXYL RADICALS
- CHLORINE
- CONDENSATION
- SUBSTITUTION REACTIONS
- NUCLEOPHILIC REACTIONS
- NITRITES
Subject Categories:
- Organic Chemistry
- Physical Chemistry
- Polymer Chemistry
- Thermodynamics