PRODUCTION OF FOAMED POLYIMIDE STRUCTURES USING MICROWAVE RADIATION,申请号AU19890035867-传众专利搜索

PRODUCTION OF FOAMED POLYIMIDE STRUCTURES USING MICROWAVE RADIATION

申请公布号：AU624821(B2)

申请号：AU19890035867

申请日期：1989.05.31

申请公布日期：1992.06.25

申请人：

ETHYL CORPORATION

发明人：RAYMOND LEE;CARROLL WENDELL LANIER;HENRY EUGENE BROEMMELSIEK

分类号：C08J9/02;B01J19/12;B29C35/08;B29C44/34;C08J9/00;C08J9/06;C08J9/10

主分类号：C08J9/02

摘要：Described are ways of improving the yields of specification grade polyimide foam on a consistent basis from one run to the next, by use of improvements in microwave-based foaming processes. While a body of polyimide precursor is exposed to microwave radiation, the body of polyimide precursor and of the foam structure as it is developing therefrom are kept under a substantially vapor-impermeable microwave-compatible shroud that does not substantially restrict or impede development of the foam structure. For this purpose use may be made of a shroud composed of a polymer film. Mechanisms by which the shroud produces the improved results are discussed, and methods based thereon are set forth.