Conductive thermoplastic composition

Abstract

Disclosed herein is a method of making conductive thermoplastic compositions, particularly conductive poly(arylene ether)/polyamide compositions using a conductive masterbatch, whereas the conductive masterbatch is made by a method comprising mixing conductive carbon black and a first resin to form a conductive carbon black/resin mixture; and compounding the conductive carbon black/resin mixture with a second resin, wherein the first resin is a powder.

1 . A thermoplastic composition made by a method comprising: 
 dry mixing conductive carbon black and a first polyamide resin, to form a conductive carbon black/first polyamide mixture;    compounding the conductive carbon black/first polyamide resin mixture with a second polyamide to form a conductive masterbatch;    compounding a poly(arylene ether) resin with a compatibilizer to form a functionalized poly(arylene ether);    compounding the functionalized poly(arylene ether) with a third polyamide resin and the conductive masterbatch wherein the first polyamide resin is a powder having a particle size of 20 micrometers to 4 millimeters.    
     
     
         2 . The thermoplastic composition of  claim 1  wherein the functionalized poly(arylene ether) is compounded with the conductive masterbatch prior to compounding with the third polyamide resin.  
     
     
         3 . The thermoplastic composition of  claim 1  wherein the compatibilizer is selected from the group consisting of citric acid, fumaric acid and maleic acid.  
     
     
         4 . The thermoplastic composition of  claim 1  wherein the first polyamide resin is polyamide 6,6.  
     
     
         5 . The thermoplastic composition of  claim 1  wherein the first and second polyamide resins are both in powder form having a particle size less than 600 micrometers.  
     
     
         6 . The thermoplastic composition of  claim 1  wherein the second polyamide resin is in pellet form and has a particle size greater than 600 micrometers.  
     
     
         7 . The thermoplastic composition of  claim 1  wherein the first and second polyamide resins are chemically identical.  
     
     
         8 . The thermoplastic composition of  claim 1  wherein the first and second polyamide resins are chemically different.  
     
     
         9 . The thermoplastic composition of  claim 1  wherein the conductive carbon black has a particle size less than 200 nanometers.  
     
     
         10 . The thermoplastic composition of  claim 1  wherein the conductive masterbatch comprises 4 to 16 weight percent conductive carbon black and 84 to 96 weight percent polyamide resin, based on the total weight of the conductive masterbatch.  
     
     
         11 . The thermoplastic composition of  claim 1  wherein the surface volume resistivity is greater than 9,600 kilo-ohm-cm.  
     
     
         12 . The thermoplastic composition of  claim 1  further comprising compounding an impact modifier with the poly(arylene ether) and compatibilizer.  
     
     
         13 . The thermoplastic composition of  claim 12  wherein the impact modifier comprises a polystyrene-polybutadiene-polystyrene block copolymer.  
     
     
         14 . The thermoplastic composition of  claim 12  wherein the Izod impact strength is greater than or equal to 54 kJ/m 2  as determined according to ISO 180.  
     
     
         15 . The thermoplastic composition of  claim 12 , wherein the thermoplastic composition has a Dynatup impact strength greater than 150% of the Dynatup impact strength of a comparable thermoplastic composition made using a first polyamide resin having a particle size greater than 4 millimeters and further wherein the Dynatup impact strengths are determined according to ASTM 256 at 23° C.  
     
     
         16 . The thermoplastic composition of  claim 12  wherein the thermoplastic composition has an Izod impact strength greater than 300% of the Izod impact strength of a comparable thermoplastic composition made using a first polyamide resin having a particle size greater than 4 millimeters, and further wherein the Izod impact strengths are determined according to ISO 180.  
     
     
         17 . The thermoplastic composition of  claim 12  wherein the melt viscosity is greater than or equal to 276 Pascal-seconds as determined by DIN54811.  
     
     
         18 . A thermoplastic composition comprising 10 to 70 weight percent poly(arylene ether); 30 to 90 weight percent of combined polyamide resin; up to 25 weight percent compatibilizer; and up to 20 weight percent of one or more impact modifiers, based on the total weight of the composition.  
     
     
         19 . The thermoplastic composition of  claim 18 , wherein the Izod impact strength is greater than or equal to 54 kJ/m 2  as determined by ISO 180; the surface volume resistivity is greater than or equal to 9,600 kilo-ohm-cm; the Dynatup impact strength is greater than or equal to 38 J as determined by ASTM 256; and the melt viscosity is greater than or equal to 276 Pascal-seconds as determined by DIN54811.