申请人:Imi-Tech Corporation
公开号:EP0349796A1
公开(公告)日:1990-01-10
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.
本发明描述了通过改进微波发泡工艺来提高聚酰亚胺泡沫塑料产量的方法。当聚酰亚胺前驱体暴露在微波辐射下时,聚酰亚胺前驱体和正在形成的泡沫结构被置于一个基本不透蒸汽的微波兼容护罩之下,该护罩不会严重限制或阻碍泡沫结构的形成。为此,可以使用由聚合物薄膜组成的护罩。本文讨论了护罩产生改进效果的机理,并阐述了基于护罩的方法。