公开(公告)号：US5338826A

公开(公告)日：1994-08-16

申请号：US954108

申请日：1992-09-28

申请人： Anne K. St. Clair ,  Terry L. St. Clair ,  William P. Winfree

发明人： Anne K. St. Clair ,  Terry L. St. Clair ,  William P. Winfree

IPC分类号： C08G73/10 ,  B05D5/06 ,  B32B27/00

CPC分类号： C08G73/1007 ,  Y10T428/31681 ,  Y10T428/31721

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.

摘要翻译： 作为电绝缘体或作为电磁能的发射器 - 接收器有效的结构通过提供合适的衬底并用低电介质，高温线性芳族聚酰亚胺的粘附层覆盖衬底来制备。 该聚酰亚胺通过以下方法制备：（1）选择芳族二胺和芳族二酐反应物以满足以下三个条件中的至少两个：（a）反应物必须具有最小的永久或可诱导的电偶极特性，这是由于存在侧基或 桥接基团; （b）由于在其中存在侧基或桥连基团，反应物必须赋予聚合物在固态中由于无效的链填料而导致的高度的自由体积; 和（c）反应物必须具有化学连接的氟原子; 和（2）将等摩尔量的芳族二胺和芳族二酐反应物在溶剂中化学组合以形成高分子量聚酰胺酸溶液，并将高分子量聚酰胺酸转化为相应的低电介质，高温线性芳族聚酰亚胺。