发明名称 |
PTC-ZUSAMMENSETZUNGEN MIT GERINGEM SPEZIFISCHEM WIDERSTAND |
摘要 |
Compositions which exhibit PTC behavior with a switching temperature (Ts) above 0 DEG C., which have a resistivity at a temperature below Ts of less than 7 ohm. cm, and which comprise a crystalline polymer and a particulate filler component which comprises carbon black having a particle size, D, which is from 20 to 150 millimicrons and a surface area S in m2/gram such that S/D is not more than 10. The composition preferably has a peak resistivity of at least 1000 ohm. cm and is electrically stable when aged at elevated temperature. The quantity <IMAGE> is preferably less than 1, especially less than 0.5. Shaped articles of such compositions are prepared by a process in which the carbon black is dispersed in the molten polymer and the dispersion is then melt-shaped, the total energy used in preparing and melt-shaping the dispersion being 1 to 300 hp. hr. ft-3, preferably 1 to 100 hp. hr. ft-3, especially 1 to 50 hp. hr. ft-3. The compositions are particularly useful in circuit protection devices. |
申请公布号 |
DE2948350(A1) |
申请公布日期 |
1980.06.19 |
申请号 |
DE19792948350 |
申请日期 |
1979.11.30 |
申请人 |
RAYCHEM CORP. |
发明人 |
VAN KONYNENBURG,PETER;AU,ANDREW;RAUWENDAAL,CHRIS;JEFFREY GOTCHER,ALAN |
分类号 |
C08K3/00;C08K3/02;C08K3/04;C08L1/00;C08L7/00;C08L21/00;C08L23/00;C08L27/00;C08L33/00;C08L33/02;C08L67/00;C08L77/00;C08L101/00;H01B1/12;H01B1/24;H01C7/02;H05B3/14;(IPC1-7):H01C7/02 |
主分类号 |
C08K3/00 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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