CN113773673A - Carbon black graphitization modification method - Google Patents

Abstract

The invention discloses a carbon black graphitization modification method, belonging to a carbon black modification method; aims to provide a method for improving the electric and thermal conductivity of carbon black. The method is that a graphite crucible is arranged in a closed graphitizing furnace; filling carbon black in the graphite crucible, and removing air in the graphitization furnace; heating the graphite crucible to 2800-3000 ℃, preserving heat for 3-5 hours, and cooling along with the furnace. The invention not only can remove sulfur in the carbon black, but also can change the microcrystal structure of the carbon black in a high-temperature solid phase, and partially graphitize aggregates which are aggregated into chain or grape-shaped structures among carbon black particles, thereby endowing the graphitized carbon atom structure with a partial graphite structure. Is a method for graphitizing and modifying carbon black.

Description

Carbon black graphitization modification method

Technical Field

The invention relates to a carbon black modification method, in particular to a method for graphitizing and modifying carbon black.

Background

The traditional carbon black modification method is mainly based on changing the element composition and surface functional groups of the carbon black, and aims to improve the dispersibility of the carbon black and endow the carbon black with good hydrophilicity. Although chinese patent documents CN107022112A (a method for graphene on the surface of carbon black) and CN112852190A (a graphene-coated carbon black material and a method for preparing the same) can form a graphene coating layer on the surface of carbon black, thereby improving the surface activity of carbon black, the distribution structure of carbon black atoms is not changed; has the defects of complex preparation process, high cost, great environmental pollution and the like.

Disclosure of Invention

In view of the above-mentioned drawbacks of the prior art, the present invention aims to provide a method for graphitizing and modifying carbon black, which is capable of partially changing the distribution structure of carbon atoms in carbon black to make the microcrystalline structure of carbon black transition from the disordered state of amorphous carbon to the ordered state of the crystalline structure of graphite.

In order to achieve the purpose, the invention adopts the following technical scheme:

1) placing the graphite crucible in a closed graphitization furnace;

2) filling carbon black in the graphite crucible, and removing air in the graphitization furnace;

3) heating the graphite crucible to 2800-3000 ℃, preserving heat for 3-5 hours, and cooling along with the furnace.

Compared with the prior art, the technical scheme is adopted, and the carbon black is subjected to graphitization modification heat treatment in an anoxic environment, so that the sulfur in the carbon black can be removed, the carbon black can be subjected to microcrystalline structure change in a high-temperature solid phase (the microcrystalline structure of the carbon black is transited from the disordered state of amorphous carbon to the ordered graphite crystalline structure), and partial graphitization change is generated on the aggregation chain-shaped or grape-shaped structure among carbon black particles, so that the carbon atomic structure subjected to graphitization has a partial graphite structure function, and the electric conduction and heat conduction performance of the carbon black can be improved.

The following is a set of data for testing the performance of two heat conductive rubbers after adding equal volume fractions of modified carbon black and unmodified carbon black to the heat conductive rubber under the same conditions:

table 1: comparison of thermal conductivity coefficients of carbon black added to heat-conducting rubber at equal volume fractions before and after graphitization modification

As can be seen from the above table, the thermal conductivity of the heat conductive rubber shows a tendency to increase with an increase in temperature; after the carbon black is subjected to graphitization modification treatment, the heat conductivity coefficient of the heat-conducting rubber filled with the modified carbon black can be greatly improved.

Detailed Description

The invention is further illustrated by the following specific examples:

1) crushing the dried carbon black to 0.3-0.5 mm, and sieving to ensure that the particle size of the carbon black under the sieve is 45-55 mu m;

2) placing the graphite crucible in a closed graphitization furnace;

3) filling the carbon black under the screen in the graphite crucible, and removing the air in the graphitization furnace;

4) heating the graphite crucible to 2800-3000 ℃, preserving heat for 3-5 hours, and cooling along with the furnace.

Claims (1)

1. A carbon black graphitization modification method is characterized by comprising the following steps:

1) placing the graphite crucible in a closed graphitization furnace;

2) filling carbon black in the graphite crucible, and removing air in the graphitization furnace;

3) heating the graphite crucible to 2800-3000 ℃, preserving heat for 3-5 hours, and cooling along with the furnace.