发明授权
- 专利标题： Structures from low dielectric polyimides
- 专利标题（中）： 低介电聚酰亚胺的结构
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申请号： US954108申请日： 1992-09-28
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公开(公告)号： US5338826A公开(公告)日： 1994-08-16
- 发明人: Anne K. St. Clair , Terry L. St. Clair , William P. Winfree
- 申请人： Anne K. St. Clair , Terry L. St. Clair , William P. Winfree
- 申请人地址： DC Washington
- 专利权人： The United States of America as represented by the Administrator of the National Aeronautics and Space Administation
- 当前专利权人： The United States of America as represented by the Administrator of the National Aeronautics and Space Administation
- 当前专利权人地址： DC Washington
- 主分类号： C08G73/10
- IPC分类号： C08G73/10 ; B05D5/06 ; B32B27/00
摘要：
A structure which is effective as an electrical insulator or as a transmitter-receiver of electromagnetic energy is prepared by providing a suitable substrate and covering the substrate with an adhering layer of a low dielectric, high temperature, linear aromatic polyimide. This polyimide is prepared by:(1) selecting aromatic diamine and aromatic dianhydride reactants to meet at least two of the following three conditions:(a) a reactant must have minimal permanent or inducible electrical dipolar characteristics as a result of the presence of pendant or bridging groups therein;(b) a reactant must impart a high degree of free volume to the polymer caused by inefficient chain packing therein in the solid state as a result of the presence of pendant or bridging groups therein; and(c) a reactant must have fluorine atoms chemically attached thereto; and(2) chemically combining equimolar quantities of the aromatic diamine and aromatic dianhydride reactants in a solvent to form a high molecular weight polyamic acid solution, and converting the high molecular weight polyamic acid to the corresponding low dielectric, high temperature linear aromatic polyimide.
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