Production of polyimide foams
AssigneeImi-Tech Corporation
InventorsRaymond Lee, Michael D. O'Donnell
Life of this patent
Estimating the term…
Abstract
A polyimide precursor mixture having a solids content of about 50 to about 77 (preferably about 65 to about 75) weight percent is subjected to a multistaged thermal treatment in which the precursor is heated to one or more temperatures sufficient to obtain a consolidated but friable cellular foam structure, and the resultant cellular foam structure is then subjected to one or more higher temperatures sufficient to cure the cellular material into a resilient polyimide foam. There is no need for use of time-consuming and expensive spray drying and microwave radiation apparatus.
Claims19
A process for the production of polyimide foams which comprises subjecting a polyimide precursor mixture having a solids content of about 50 to about 75 weight percent by first heating said mixture to a foaming temperature in the range of about 135.degree. to about 170.degree. C. to form a consolidated but friable cellular foam structure and then subjecting said friable cellular foam structure to a temperature of at least about 230.degree. C. to cure the cellular material into a resilient polyimide foam.
Dependencies are inferred from the claim text.