Claims
- 1. An electrically conductive solid thermoplastic, which consists essentially of:
- a) bead-shaped particles of substantially non-crystalline polymethyl methacrylate polymer having a mean particle diameter in the range of about 10-1,000 .mu.m, and
- b) carbon black, as an electrically conducting substance, substantially all of which is present on the surface of said polymer particles, in an amount of 0.05-5 wt. %, based on the weight of the polymer, wherein said electrically conductive substance is in the form of a plurality of conducting particulate solid bodies, and further wherein the glass transition temperature of said polymer is not exceeded when the conducting substance is mixed with said polymer particles.
- 2. The electrically conductive solid thermoplastic of claim 1, wherein said bead-shaped polymer particles have a mean particle diameter in the range of 30-300 .mu.m.
- 3. The electrically conductive solid thermoplastic of claim 1, wherein said bead-shaped polymer particles have a mean particle diameter in the range of 30-100 .mu.m.
- 4. The electrically conductive solid thermoplastic of claim 1, wherein greater than 95% of the bead-shaped polymer particles have a particle size distribution in the range of about 10-1,000 .mu.m.
- 5. The electrically conductive solid thermoplastic of claim 1, wherein greater than 99% of the bead-shaped polymer particles have a particle size distribution in the range of about 10-1,000 .mu.m.
- 6. The electrically conductive solid thermoplastic of claim 1, wherein said polymer particles are produced by a bead polymerization technique.
- 7. The electrically conductive solid thermoplastic of claim 1, wherein the amount of said carbon black is 0.1-5.0 wt. % based on the weight of the polymer.
- 8. The electrically conductive solid thermoplastic of claim 1, wherein the surface per unit weight value of said conductive carbon black is 15-1,500 m.sup.2 /g.
- 9. The electrically conductive solid thermoplastic of claim 1, further comprising finely dispersed inert inorganic filler, in an amount of up to 70 wt. % of the total weight of the plastic.
- 10. The electrically conductive solid thermoplastic of claim 1, wherein said conductive substance is mixed with said polymer particles by a fluidized bed technique.
- 11. The electrically conductive solid thermoplastic of claim 1, wherein said conductive substance is mixed with said polymer particles by a milling or grinding technique.
- 12. The electrically conductive solid thermoplastic of claim 1, wherein said thermoplastic is produced by:
- a) mixing at ambient temperature said polymer particles, and said conductive particulate solid bodies, top thereby coat substantially all of said bodies on the surface of said polymer particles; and
- b) sintering the coated polymer particles, thereby forming said solid conductive bodies.
Priority Claims (1)
Number |
Date |
Country |
Kind |
3543301 |
Dec 1985 |
DEX |
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Parent Case Info
This application is a continuation of application Ser. No. 259,432, filed on Oct. 18, 1988, now abandoned, which is a continuation of application Ser. No. 06/935,201, filed on Nov. 26, 1986, now abandoned.
US Referenced Citations (11)
Foreign Referenced Citations (4)
Number |
Date |
Country |
723598 |
Feb 1955 |
GBX |
858530 |
Jan 1961 |
GBX |
929733 |
Jun 1963 |
GBX |
2076420 |
Feb 1981 |
GBX |
Continuations (2)
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Number |
Date |
Country |
Parent |
259431 |
Oct 1988 |
|
Parent |
935201 |
Nov 1986 |
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