| 摘要 |
Foamed polymers having low loss at microwave frequencies are prepared through use of perfluorinated alkane foaming agents. The invention is particularly valuable for polymers which are melt-processed at high temperatures, especially fluoropolymers such as tetrafluoroethylene copolymers. The polymeric foams are particularly useful as electrical insulation, especially for coaxial cables suitable for use at microwave frequencies. |
