Method for preparing graphene, preparation method of graphene slurry, graphene grinding and dispersing machine, graphene high-shear grinding and dispersing machine, and method for preparing graphene slurry grinder graphene since graphene was discovered, researchers made a  a great effort on graphene preparation in batches and has achieved the staged achievements. The main methods for preparing graphene are: 

(1) A crystal epitaxial growth method in which a single crystal silicon carbide substrate is heated to 1200 to 1600 ° C under an extremely high degree of vacuum, and silicon atoms in the substrate are sublimated and precipitated, and excess carbon atoms remain on the substrate for reconstruction to produce graphene, which is currently recognized as one of the possible ways to achieve industrialization; (2) chemical vapor deposition (CVD), which decomposes carbonaceous compounds such as methane on the substrate for reformation of graphene, and then remove the metal substrate to obtain graphene; (3) chemical oxidation-reduction method, currently there are three main ways to prepare graphite oxide by this method, namely Brodie method, Staudenmaier method and Hummers method. The former two will produce ClO2 gas, and the Hummers redox method has a short reaction time, and the product purification step is simple, so the current preparation method is mostly based on the Hummers redox method. 

The Hummers redox process is summarized as follows:

1 adding graphite to a strong acid and strong oxidant mixture to obtain graphite oxide; 2 obtaining graphene oxide (GO) by external force stripping; 3 reducing graphene oxide by chemical reduction, thermal reduction, etc. to obtain reduced graphene oxide (rGO) ).

Among the above three preparation methods, the large-area graphene sheets obtained by the CVD method can be directly coated on the metal surface to serve as an anticorrosive and protective coating, while the chemical oxidation-reduction method is more commonly used in the field of coatings. This is because the active oxygen-containing group is introduced into the graphene during the oxidation process, which provides an active reaction site for the later functional modification, enriching the means of functional modification, thereby effectively improving the modified GO. Compatibility with solvents and polymers. 

Method for preparing graphene slurry

(1) Ultrasonic dispersing equipment: It is very suitable for laboratory scale, low viscosity medium dispersing graphene. It is limited when used for medium and high viscosity medium, and the processing volume is relatively small, which is not suitable for scale production. (2) Sand mill: able to uniform refinement of the particle size of graphene, but it needs long working time and is easy to destroy the atomic mechanism of graphene, so it has high cost of consumable replacement.(3) Using a grinding and dispersing machine to first open the particle size of the agglomerate for restoration of original particle size and then the material is refined and peeled off. It can efficiently obtain the ideal graphene slurry. Graphene grinding and dispersing machine is grinding: using shear force, friction or impact force to make the powder from large particles to  peel off into small particles by the pulverization.

Dispersion: Nano-powders are coated with solvents, additives, dispersants, resins, etc., so that the particles are completely separating, wetting, distributing, and stabilizing.

(Photo: Electron micrograph of graphene aqueous solution handled by Suzhou NAPO nanodispersion technology)

Three elements of graphene slurry dispersion technology

Secondly, the recommended amount of dispersant  

Thirdly, graphene water dispersant overview

Fourthly, the use of ultrasonic dispersion equipment recommendations and dispersion examples

Fifthly, grinding and dispersing equipment use recommendations

Three elements of graphene dispersion technology: dispersion medium, dispersant and dispersion equipment. IKN graphene grinding and dispersing machine is a high-tech product composed of a combination of a grinder and a dispersing machine.

The first stage consists of a multi-stage serrated protrusion and groove with a fine rise. The stator can be adjusted without limitation to the required distance from the rotor. Under enhanced fluid turbulence, the grooves can change direction at each stage.

The second stage consists of a rotating stator. The design of the dispersion head also satisfies the needs of materials of different viscosities as well as particle size. The difference between the design of the on-line stator and rotor (emulsifier head) and the batch head of the batch machine is mainly due to the fact that in terms of the transportability requirements, and particular attention should be paid to: the difference between some work head types on coarse precision, medium precision, fine precision is not only the arrangement of the specified rotor teeth, but also a very important difference is that the geometric characteristics of the different work heads are different. The number of slots, slot width, and other geometric features can change the different functions of the stator and rotor heads. According to past practice, the work head is specified according to previous experience to meet a specific application. In most cases, the construction of the machine is matched to the specific application, so it is important to make the final product. When it is uncertain whether the construction of a work head satisfies the intended application.

The CMD2000 series has a high line speed and a very small shear gap, so that when the material passes, the friction is more severe. The result is the so-called wet grinding. The stator is made into a circular cone shape with a multi-stage serrated protrusion and groove with a fine rise. The stator can be adjusted without limitation to the required distance from the rotor. Under enhanced fluid turbulence, the grooves can change direction at each stage. High quality surface finishes and structural materials to meet a wide range of requirements in different industries.　

IKN graphene grinding equipment adopts Germany's advanced high-speed grinding and dispersing technology to drive ultra-high precision grinding head rotor (usually equipped with CM+8SF and stator-rotor clearance is between 0.2-0.3) through ultra-high speed to make graphene slurry to form the turbulent flow at the high line speed of the equipment, and it is continuously impacted, crushed, grounded, dispersed and homogenized in the stator rotor gap, thereby obtaining ultrafine particles (of course, a suitable dispersant is also required as an auxiliary agent). Combining the above points can lead to an ideal conductive graphene slurry.