1. A thermoplastic resin composition having electrical conductivity, wear resistance and high heat resistance, comprising:
(A) about 50 to about 90% by weight polyphenylene sulfide resin; and
(B) about 5 to about 30% by weight graphite; and
(C) about 5 to about 30% by weight fluoropolyolefin resin; and
(D) about 1 to about 10% by weight whiskers; and
(E) about 0.01 to about 10% by weight carbon nanotubes.
2. The thermoplastic resin composition of claim 1, wherein the polyphenylene sulfide resin (A) has a weight average molecular weight (Mw) of about 3,000 to about 50,000 gmol.
3. The thermoplastic resin composition of claim 1, wherein the graphite (B) has an average particle size of about 0.5 to about 300 \u03bcm.
4. The thermoplastic resin composition of claim 1, wherein the graphite (B) is surface-treated with an alkaline earth metal compound, silane coupling reagent, titanium coupling reagent, aluminum coupling reagent, or a combination thereof.
5. The thermoplastic resin composition of claim 1, wherein the fluoropolyolefin resin (C) has an average particle size of about 3 to about 50 \u03bcm and a specific gravity of about 1.2 to about 2.3 gcm3.
6. The thermoplastic resin composition of claim 1, wherein the whiskers (D) have an average diameter of about 0.15 to about 10 \u03bcm and an average length of about 2 to about 100 \u03bcm.
7. The thermoplastic resin composition of claim 1, wherein the whiskers (D) comprise zinc oxide whiskers, calcium carbonate whiskers, titanium dioxide whiskers, silicon dioxide whiskers, silicon carbide whiskers, aluminum borate whiskers, magnesium borate whiskers, potassium titanate whiskers, silicon nitride whiskers, silicon carbide whiskers, aluminum oxide whiskers, or a combination thereof.
8. The thermoplastic resin composition of claim 1, wherein the whiskers (D) include calcium carbonate (CaCO3) whiskers.
9. The thermoplastic resin composition of claim 1, wherein the whiskers (D) are coated with a conductive material.
10. The thermoplastic resin composition of claim 9, wherein the conductive material comprises silver, copper, aluminum, iron, palladium, tin oxide, indium oxide, silicon carbide, zirconium carbide, titanium carbide, graphite, or a combination thereof.
11. The thermoplastic resin composition of claim 1, wherein the carbon nanotubes (E) comprise single-walled carbon nanotubes, double-walled carbon nanotubes, multi-walled carbon nanotubes or a combination thereof.
12. The thermoplastic resin composition of claim 1, wherein said carbon nanotubes (E) have an average external diameter of about 0.5 to about 100 nm and an average length of about 0.01 to about 100 \u03bcm.
13. The thermoplastic resin composition of claim 1, further comprising an additive comprising a flame retardant, antimicrobial agent, mold release agent, heat stabilizer, antioxidant agent, light stabilizer, compatibilizing agent, dye, pigment, coupling agent, charging material, plasticizer, impact modifier, lubricant, antistatic agent, or a combination thereof.
14. A plastic product manufactured from the thermoplastic resin composition of claim 1.
15. The plastic product of claim 14, wherein the plastic product is a printer bushing.
16. A thermoplastic resin composition comprising polyphenylene sulfide resin in which graphite, fluoropolyolefin resin, whiskers and carbon nanotubes are dispersed, and having a surface resistance of about 106 \u03a9sq or less measured according to ASTM D257, a dynamic friction coefficient of about 0.16 or less measured according to JIS K 7218, an abrasion loss of about 16 mg or less measured after the steps of preparing a specimen of 10 cm\xd710 cm of the resin composition; and rubbing the specimen with two round shaped aluminum-pieces with a 5 cm diameter using a Taber fiction tester during 10,000 cycles at 90 rpm according to ASTM D4060 and a thermal modification temperature of about 245\xb0 C. or more at a pressure of 0.45 MPa measured according to ASTM D648.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
I claim:
1. A positioning system for determining a position and obtaining information about that position comprising:
a. means for communicating with a reference station, using a packet radio format, for receiving positioning transmissions and obtaining information about the position from the reference station; and
b. means for determining a position coupled to the means for communicating for determining the position of the positioning system based on the positioning transmissions.
2. The positioning system as claimed in claim 1 further comprising a user interface coupled to the means for communicating for allowing a user to communicate through the positioning system to the reference station.
3. The positioning system as claimed in claim 2 wherein the reference station includes an information system having a data storage memory and retrieval system.
4. The positioning system as claimed in claim 3 wherein the reference station further includes a direct internet connection allowing the user to access the internet through the positioning system.
5. The positioning system as claimed in claim 4 wherein the packet radio format is CDPD.
6. The positioning system as claimed in claim 1 wherein the positioning transmissions are transmitted from the reference station having a known amplitude and known signal strength and are received by the means for communicating having a received amplitude and received signal strength and further wherein the means for determining determines the position based on the difference between the known and received amplitudes and the known and received signal strengths.
7. The positioning system as claimed in claim 1 further comprising means for automatically and periodically providing the position to the reference station.
8. The positioning system as claimed in claim 7 wherein the reference station includes means for tracking and monitoring the position of the positioning system.
9. The positioning system as claimed in claim 8 wherein the reference station further includes means for sending an alert coupled to the means for tracking and monitoring for sending an alert to a predetermined location if the position of the positioning system is equal to a predetermined alert position.
10. A method of determining a position and obtaining information about the position comprising the steps of:
a. receiving positioning transmissions in a packet radio format;
b. determining a position of the positioning system based on the positioning transmissions; and
c. communicating with a reference station using a packet radio format to obtain information about the position from the reference station.
11. The method as claimed in claim 10 wherein the positioning transmissions are received from a plurality of reference stations, each reference station sending position transmissions having a known amplitude and known signal strength.
12. The method as claimed in claim 11 wherein the position is determined based on the difference between the known amplitude and a received amplitude of each positioning transmission received from each respective reference station and the difference between the known signal strength and a received signal strength of each positioning transmission received from each respective reference station.
13. The method as claimed in claim 10 further comprising the step of providing an interface to a user thereby allowing the user to communicate with the reference station.
14. The method as claimed in claim 13 further comprising the step of automatically and periodically providing the position to the reference station.
15. The method as claimed in claim 14 further comprising the step of monitoring the position.
16. The method as claimed in claim 15 further comprising the step of providing an alert if the position is equal to a predetermined position.
17. A system for determining a position and obtaining information about that position comprising:
a. a plurality of reference stations each including a first communications circuit for sending and receiving communications in a packet radio format, wherein the communications include positioning transmissions having a known amplitude and known signal strength; and
b. a positioning system including:
i. a second communications circuit for communicating with the first communications circuit in the packet radio format and receiving the positioning transmissions, which when received have a received amplitude and a received signal strength; and
ii. a position determining circuit for determining the position of the positioning system based on the difference between the known amplitude and signal strength and the received amplitude and signal strength of the positioning transmissions received from each of the plurality of reference stations.
18. The system as claimed in claim 17 wherein the positioning system further includes an interface coupled to the second communications circuit for interfacing with a user and allowing the user to obtain information from the reference station and to provide information to the reference station.
19. The system as claimed in claim 18 wherein each reference station further includes an information system for storing and retrieving information.
20. The system as claimed in claim 19 wherein the information system includes a data storage memory and retrieval system.
21. The system as claimed in claim 20 wherein the information system includes a direct internet connection allowing the user to have direct access to information on the internet.
22. The system as claimed in claim 21 wherein the packet radio format is a CDPD format.
23. The system as claimed in claim 17 wherein the second communications circuit automatically and periodically provides the position to the reference station.
24. The system as claimed in claim 23 wherein the reference station further includes a monitoring device coupled to the first communications circuit for monitoring the position of the positioning system.
25. The system as claimed in claim 24 wherein the reference station further includes an alerting device coupled to the monitoring device for sending an alert to a predetermined location if the position of the positioning system is equal to a predetermined position.
26. A system for determining and monitoring a position of a positioning system comprising:
a. a positioning system including:
i. a first communications circuit for sending and receiving communications in a packet radio format including receiving positioning transmissions having a received amplitude and a received signal strength and automatically and periodically transmitting a position of the positioning system in a packet radio format; and
ii. a determining circuit coupled to the first communications circuit for determining the position of the positioning system based on the received amplitude and signal strength of the positioning transmissions; and
b. a plurality of reference stations each including:
i. a second communications circuit for communicating with the first communications circuit in the packet radio format, receiving the position and transmitting the positioning transmissions at a known amplitude and known signal strength; and
ii. a monitoring circuit coupled to the second communications circuit for monitoring and racking the position.
27. The system as claimed in claim 26 wherein each of the reference stations further include an alerting device coupled to the monitoring device for sending an alert if the position of the positioning system is equal to a predetermined position.