摘要 |
Conductive polymer PTC compositions have improved properties, especially at voltage of 200 volts or more, if they are very highly cross-linked by means of irradiation, for example to a dosage of at least 50 Mrads, preferably at least 80 Mrads, e.g. 120 to 600 Mrads. The cross-linked compositions are particularly useful in circuit protection devices and layered heaters.
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