Electrically conductive compositions and method of manufacture thereof

Abstract

Disclosed herein is a method of manufacturing an electrically conductive composition comprising reducing the viscosity of a molten masterbatch to form a reduced viscosity molten masterbatch; and mixing the reduced viscosity molten masterbatch with a polymer to form the electrically conductive composition. Disclosed herein too is a method of manufacturing an electrically conductive composition comprising mixing a molten masterbatch with a first polymer in a first extruder, wherein the first polymer has a melt viscosity that is lower than the melt viscosity of the molten masterbatch; reducing the melt viscosity of the molten masterbatch to form a reduced viscosity molten masterbatch; and mixing the reduced viscosity molten masterbatch with a second polymer in a second extruder to form the electrically conductive composition.

1 . A method of manufacturing an electrically conductive composition comprising:
 reducing a melt viscosity of an electrically conductive molten masterbatch comprising a polymer and an electrically conductive filler, to form a reduced viscosity molten masterbatch; wherein the melt viscosity of the electrically conductive molten masterbatch is reduced by mixing it with a diluent, a plasticizer, a polymer having a melt viscosity that is lower than the melt viscosity of the electrically conductive molten masterbatch, or a combination thereof, and   mixing the reduced viscosity molten masterbatch with a molten second polymer to form the electrically conductive composition; wherein a melt viscosity of the reduced viscosity molten masterbatch is equal to a melt viscosity of the molten second polymer at an initial point of contact.   
   
   
       2 . A method of manufacturing an electrically conductive composition comprising:
 mixing an electrically conductive molten masterbatch comprising a polymer and an electrically conductive filler with a first polymer in a first extruder, wherein the first polymer has a melt viscosity that is lower than a melt viscosity of the electrically conductive molten masterbatch;   reducing the melt viscosity of the electrically conductive molten masterbatch to form a reduced viscosity molten masterbatch; and   mixing the reduced viscosity molten masterbatch with a second polymer in a second extruder to form the electrically conductive composition; wherein a melt viscosity of the reduced viscosity molten masterbatch is equal to a melt viscosity of the second polymer at an initial point of contact in the second extruder.   
   
   
       3 . The method of  claim 2 , wherein the electrically conductive filler is carbon black, carbon nanotubes, carbon fibers, metallic fillers, non-conductive fillers coated with metallic coatings, electrically conductive non-metallic fillers, or a combination comprising at least one of the foregoing electrically conductive fillers. 
   
   
       4 . The method of  claim 3 , wherein the carbon nanotubes are single wall carbon nanotubes, multiwall carbon nanotubes, vapor grown carbon fibers, or a combination comprising at least one of the foregoing carbon nanotubes. 
   
   
       5 . The method of  claim 2 , wherein the electrically conductive molten masterbatch comprises up to about 50 wt % of the electrically conductive fillers, based on the weight of the electrically conductive molten masterbatch. 
   
   
       6 . The method of  claim 2 , wherein the first extruder is a side compounder to the second extruder. 
   
   
       7 . The method of  claim 2 , wherein the first polymer is the same as the second polymer. 
   
   
       8 . The method of  claim 2 , wherein the first polymer is different from the second polymer. 
   
   
       9 . The method of  claim 2 , wherein the first polymer and the second polymer are compatibilized in the electrically conductive composition. 
   
   
       10 . The method of  claim 2 , wherein the first polymer and/or the second polymer is a thermoplastic, a thermoset, or a combination of a thermoplastic with a thermoset. 
   
   
       11 . The method of  claim 2 , wherein the first polymer and/or the second polymer is a polyacetal, a polyacrylic, a polyarylene ether, a polycarbonate, a polystyrene, a polyester, a polyamide, a polyamideimide, a polyarylate, a polyurethane, a polyarylsulfone, a polyethersulfone, a polyarylene sulfide, a polyvinyl chloride, a polyetherimide, a polyimide, a polytetrafluoroethylene, a polyetherketone, a polyether ether ketone or a combination comprising at least one of the foregoing polymeric resins. 
   
   
       12 . The method of  claim 2 , wherein the first polymer is a polyamide and wherein the second polymer is a polyarylene ether. 
   
   
       13 . The method of  claim 2 , wherein the electrically conductive composition comprises a compatibilizer and an impact modifier. 
   
   
       14 . The method of  claim 2 , wherein the electrically conductive composition has a specific volume resistivity of less than or equal to about 10e 8  ohm-cm, a notched Izod impact strength of greater than 10 kilojoules/square meter and a Class A surface finish. 
   
   
       15 . The method of  claim 2 , wherein the electrically conductive composition has a specific volume resistivity of less than or equal to about 10e 8  ohm-cm and a notched Izod impact strength of greater than 15 kilojoules/square meter. 
   
   
       16 . The method of  claim 2 , wherein the electrically conductive composition has a specific volume resistivity of less than or equal to about 10e 8  ohm-cm, a notched Izod impact strength of greater than 10 kilojoules/square meter and a Class A surface finish. 
   
   
       17 . An article manufactured by the method of  claim 3 , wherein the resistivity ratio of the electrically conductive composition is greater than or equal to 0.5. 
   
   
       18 . The article of  claim 17 , wherein the article is an automobile part. 
   
   
       19 . The article of  claim 18 , wherein the automobile part is an exterior body panel, a fender or a dashboard. 
   
   
       20 . A method of manufacturing an electrically conductive composition comprising:
 mixing an electrically conductive molten masterbatch comprising a polyamide and an electrically conductive filler with a polyamide in a first extruder, wherein the polyamide has a melt viscosity that is lower than a melt viscosity of the molten masterbatch;   reducing the melt viscosity of the molten masterbatch to form a reduced viscosity molten masterbatch; and   mixing the reduced viscosity molten masterbatch with a molten polyarylene ether in a second extruder to form the electrically conductive composition wherein a melt viscosity of the reduced viscosity molten masterbatch is equal to a melt viscosity of the polyarylene ether at an initial point of contact in the second extruder.   
   
   
       21 . The method of  claim 20 , wherein the molten masterbatch comprises a polyamide and carbon nanotubes. 
   
   
       22 . The method of  claim 20 , wherein the polyarylene ether is compatibilized with a polyamide prior to the mixing with the reduced viscosity molten masterbatch. 
   
   
       23 . The method of  claim 20 , further comprising molding the electrically conductive composition. 
   
   
       24 . An article manufactured by the method of  claim 20 , wherein the resistivity ratio of the electrically conductive composition is greater than or equal to 0.5. 
   
   
       25 . The article of  claim 24 , wherein the article is an automobile part. 
   
   
       26 . The article of  claim 25 , wherein the automobile part is an exterior body panel, a fender or a dashboard. 
   
   
       27 . A method of manufacturing a composition comprising:
 melting a masterbatch comprising a polymer and an electrically conductive filler to form an electrically conductive molten masterbatch in a first extruder;   reducing the viscosity of the electrically conductive molten masterbatch in the first extruder; and   mixing the reduced viscosity molten masterbatch with a molten second polymer in a second extruder to form the composition wherein a melt viscosity of the reduced viscosity molten masterbatch is equal to a melt viscosity of the second polymer at an initial point of contact in the second extruder.   
   
   
       28 . The method of  claim 27 , wherein the masterbatch further comprises fillers and/or additives that are non-electrically conductive. 
   
   
       29 . The method of  claim 28 , wherein the non-electrically conductive fillers are anti-oxidants, anti-ozonants, dyes, colorants, infrared light absorbers, ultraviolet light absorbers, reinforcing fillers, compatibilizers, plasticizers, fibers, or a combination comprising at least one of the foregoing non-conductive fillers. 
   
   
       30 . An article manufactured by the method of  claim 29 , wherein the resistivity ratio of the electrically conductive composition is greater than or equal to 0.5.