| 摘要 |
PURPOSE:To obtain the titled stable composition with PTC characteristics, free from thermal history, by crosslinking a mixture of polyethylene oxide and electrically conductive powder. CONSTITUTION:For example, in case a chemically crosslinking process is to be performed, a mixture of (A) 100pts.wt. of polyethylene oxide and (B) 10-100 pts.wt. of electrically conductive powder (pref. electrically conductive carbon black or graphite) is incorporated with (1) 0.5-5pts.wt. of a crosslinking agent (e.g. organic peroxide) plus crosslinking promoter (e.g. triallyl isocyanurate) and, preferably, (2) 0.5-5pts.wt. of a deterioration inhibitor (pref. of phenolic or hindered phenolic base), (3) 1-10pts.wt. of a surfactant (pref. sodium naphthalene sulfonate) and (4) <=50pts.wt. of a temperature characteristics improver (pref. paraffin wax) followed by crosslinking in an inert gas atmosphere, in a vacuum or heating medium.
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