Approaches to Ladder Structures. VI. Condensation Polymerization of Some Difunctional Derivatives Related to (4H), 3, 1-Benzoxazine-4-One with Certain Aromatic Diamino Dicarboxylic Acids, Esters or Aromatic Tetraamines
AIR FORCE MATERIALS LAB WRIGHT-PATTERSON AFB OH
The compounds 2,7-dimethyl-4H,9H,3,1,8,6-benzobisoxazine-4,9-dione, and 6,6-bis-2-methyl-4H,3,1-benzoxazine-4-one condense on heating at 300C either in the melt or in solution in sulfolane or molten benzophenone to give insoluble highly condensed cross-linked polymers. High molecular weight or cross-linked materials were obtained when 2,7-bis-trifluoro-methyl-4H,9H,3, 1,8,6-benzobisoxazine-4,9-dione, and 6,6-bis-2-trifluoromethyl-4H,3,1- benzoxazine-4-one were similarly treated. 2-methyl-4H,3,1benzoxazine-4-one reacted with methyl anthranilate in refluxing xylene to give 3-methyl-3-o- carboxymethyl-phenylquinazoline-4-one. Polyquinazolinones in the medium molecular weight range were obtained when 2,7-dimethyl-4H,9H,3,1,8,6- benzobisoxazine-4,9-dione was reacted with either 2,5-diamino-terephthalic acid or its diethyl ester in sulfolane or diphenylether up to 300C. 2,7-dimethyl-4H, 9H,3,1,8,6-benzobisoxazine-4,9-dione and 3,3diamino-benzidine were reacted in dimethylformamide, diethyl cellosolve, and trimethylene glycol dimethyl ether to give a soluble low molecular weight linear polyamide expected to use as a prepolymer for subsequent conversion to the corresponding quinazoline and benzimidazo-1,2c-quinazoline polymers.
Technical rept. Mar 1967-Aug 1969
See also AD878738.