A conductive carbon powder, a method for the manufacturing thereof and use thereof

Abstract

The present invention relates to a conductive carbon powder emanating essentially from lignin, a method for the manufacturing thereof and use thereof. Said powder may emanate from an electrically conductive carbon intermediate product, in turn emanating essentially from lignin Further, uses thereof and compositions comprising said carbon powder are disclosed. Additionally methods for manufacturing said conductive carbon powder, also involving an electrically conductive carbon intermediate product emanating essentially from lignin, are disclosed together with a method for making said compositions.

1 . An electrically conductive carbon powder emanating essentially from lignin. 
     
     
         2 . An electrically conductive carbon intermediate product emanating essentially from lignin, having the form of a powder or a shaped body such as, a wafer, a bar, rod, film, filament or fleece. 
     
     
         3 . A method for manufacturing a conductive carbon powder comprising the following steps:
 a) thermal treatment of a lignin comprising compound to increase the carbon content to at least 80% to obtain an electrically conductive carbonized lignin intermediate product and   b) mechanical treatment of the electrically conductive carbonized lignin intermediate product to obtain a carbonized lignin powder which is electrically conductive.   
     
     
         4 . A method for manufacturing an electrically conductive carbon powder comprising the following steps:
 i) providing a lignin and at least one additive,   ii) mixing said components,   iii) shaping said mixture to form a shaped body,   iv) performing a thermal treatment of said shaped body in at least one step of which the last step comprises a temperature ramp from room temperature to up to about 2000° C. in inert atmosphere, thus providing a conductive carbonized intermediate product   v) pulverizing said conductive carbonized intermediate product, thus providing a conductive carbon powder.   
     
     
         5 . A method according to  claim 4  wherein the additive is a poly ethylene glycol 
     
     
         6 . A method according to  claim 4  wherein the temperature ramp from room temperature is up to about 1600° C. 
     
     
         7 . A method for manufacturing a carbonized intermediate product in filament form, comprising the following steps:
 vi) providing a lignin and at least one additive,   vii) mixing said components and melt spinning said mixture to a monofilament or multifilament bundle component,   viii) performing a thermal treatment of said shaped body in two steps of which the last step comprises a temperature ramp from room temperature to up to about 2000° C. in inert atmosphere thus providing a conductive carbonized intermediate product in filament form.   
     
     
         8 . A method according to  claim 4  wherein the temperature ramp from room temperature is up to about 1400° C. 
     
     
         9 . An electrically conductive carbon powder obtainable by the method according to  claim 3 . 
     
     
         10 . A conductive carbonized intermediate product in filament form obtainable by the method according to  claim 7 . 
     
     
         11 . (canceled) 
     
     
         12 . (canceled) 
     
     
         13 . A composition comprising a conductive carbon powder according to  claim 1  and a polymer. 
     
     
         14 . A composition according to  claim 13  wherein the polymer is a thermoplastic or thermoset used for the manufacture of electrically conductive compounds, or a mixture of such polymers. 
     
     
         15 . A composition according to  claim 13  wherein the polymer is a polyolefin, a co-polymer comprising a polyolefin or a mixture of polyolefins. 
     
     
         16 . A composition according to  claim 13  wherein the polymer is a polypropylene (PP). 
     
     
         17 . A composition according to  claim 13  wherein the conductive carbon powder when compounded gives a percolation threshold in the polymer compound at 1-40% addition level. 
     
     
         18 . A composition according to  claim 13  wherein the conductive carbon powder when compounded lowers the volume resistivity of the polymer compound after the percolation point to 10 0 -10 6  Ω·cm. 
     
     
         19 . A method for the manufacturing of a composition according to  claim 13  comprising mixing a conductive carbon powder with a polymer. 
     
     
         20 . A polymer composition obtainable by a method according to  claim 19 . 
     
     
         21 . (canceled) 
     
     
         22 . A polymer composition for a semi-conductive layer of a cable comprising a conductive carbon powder according to  claim 1  and a thermoplastic or a thermoset or a mixture thereof. 
     
     
         23 . A polymer composition for a semi-conductive layer of a cable according to  claim 22  wherein the thermoplastic is a polyolefin, a co-polymer comprising a polyolefin or a mixture of polyolefins. 
     
     
         24 . A composition according to  claim 13 , wherein said polymer is a thermoplastic or a thermoset or a mixture of such polymers. 
     
     
         25 . A method for the manufacturing of a composition according to  claim 19 , wherein said polymer is a thermoplastic or a thermoset or a mixture thereof.