Polyimide prepolymer molding powders
Abstract
Abstract WHEREIN R IS SELECTED FROM THE GROUP CONSISTING OF HYDROGEN, LOWER ALKYL RADICALS HAVING 1 TO 5 CARBON ATOM AND COMBINATIONS THEREOF. PHTHALAN 1,3-DI(O=),3A,7A-DI(R-),R-3A,4,7,7A-TETRAHYDRO-4,7-METHANO THIS INVENTION RELATES TO POLYIMIDE PREPOLYMER POWDERS AND TO THE PROCESS FOR PREPARING SAME, AND MORE SPECIFICALLY, TO POLYIMIDE PREPOLYMER MOLDING POWDERS HAVING PARTICLES WITH SURFACE AREAS RANGING FROM ABOUT 1 TO 800 SQUARE METERS PER GRAM. MORE PARTICULARLY, THIS INVENTION RELATES TO MOLDING POWDERS PREPARED FROM POLYIMIDE PREPOLYMERS HAVING AN AVERAGE MOLECULAR WEIGHT RANGING FROM ABOUT 500 TO 6,000. THE PREPOLYMERS ARE PREPARED BY REACTING APPROXIMATELY STOICHIOMETRIC AMOUNTS OF AT LEAST ONE POLYFUNCTIONAL AMINE, E.G., AN AROMATIC DIAMINE, ONE OR MORE POLYFUNCTIONAL ANHYDRIDES AND A MONOHYDRIDE CHARACTERIZED BY THE FORMULA:
Inventors
- 👤 Hyman R Lubowitz
- 👤 William P Kendrick
- 👤 John F Jones
- 👤 Eugene A Burns
Bibliographic Details
Claims Analysis
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