How To Improve The Dispersion Uniformity Of Carbon Fibers In The EVA Matrix? - Carbon Fiber Compounds Manufacturer | Supplier

How to improve the dispersion uniformity of carbon fibers in the EVA matrix?

Surface Modification

– Chemical Oxidation Method：

The chemical oxidation method uses strong oxidants to treat the surface of carbon fibers, introducing oxygen-containing functional groups such as carboxyl and hydroxyl groups, which enhances the compatibility with the EVA matrix and is beneficial for dispersion. For example, nitric acid can oxidize carbon fibers to generate functional groups. However, parameters like the concentration of the oxidant, treatment time, and temperature need to be strictly controlled to prevent damage to the performance of carbon fibers. Multiple experiments are required to determine the optimal conditions.

– Coupling Agent Treatment：

Coupling agent treatment relies on its bifunctional group structure to improve the compatibility between carbon fibers and the EVA matrix. One end reacts with carbon fibers, and the other end interacts with EVA, acting as a connecting bridge. Appropriate coupling agents should be selected according to the characteristics of both, and the optimal addition amount should be determined through experiments to avoid affecting the overall performance of the material.

– Plasma Treatment：

Plasma treatment utilizes the interaction between plasma and the surface of carbon fibers to change their surface properties, increasing roughness and active functional groups, and improving the wettability and binding force with EVA, which helps with dispersion. However, treatment parameters need to be carefully adjusted to ensure the stability and safety of the treatment process and achieve the desired dispersion effect.

Addition of Dispersants

– Selection of Appropriate Dispersant Types：

Different types of dispersants have different action mechanisms. Polyether-based dispersants rely on the hydrophilicity of ether bonds, fatty acid-based dispersants depend on their long-chain structure, and polymer-based dispersants use functional groups to improve the dispersion of carbon fibers. Multiple factors should be considered comprehensively to select the appropriate type. For example, the polyether-based dispersant S-100 can be tried for the dispersion of carbon fibers in EVA, and other methods need to be combined to optimize the effect.

– Determination of Appropriate Addition Amount：

The addition amount of dispersants affects the dispersion effect and the performance of the material. If it is too little, carbon fibers cannot be fully dispersed. If it is too much, it will affect the performance of the matrix and the interaction with carbon fibers. Experiments are needed to explore the optimal amount to balance the dispersion effect and the overall performance of the material and determine the optimal dosage range.

Optimization of Processing Technology

– Adoption of Appropriate Mixing Equipment：

Equipment such as high-shear mixers, powerful agitators, and twin-screw extruders can generate shear forces to help disperse carbon fibers in EVA. Different equipment has its optimal parameters and application ranges. Reasonable selection and adjustment should be made according to the characteristics of carbon fibers and EVA as well as the production scale to give play to their advantages and achieve good dispersion.

– Control of Processing Parameters：

Parameters such as processing temperature, pressure, and stirring time affect the dispersion of carbon fibers in EVA. Appropriate increase in temperature can reduce the viscosity to assist dispersion, but excessive temperature will cause EVA degradation. Reasonable pressure ensures compaction and mixing, and excessive stirring time will break carbon fibers. Multiple experiments are needed to determine the optimal combination of parameters.

– Pre-dispersion Treatment：

Pre-dispersion treatment first forms a suspension of carbon fibers in a solvent through ultrasonic treatment and then mixes it with EVA, which can better disperse carbon fibers and remove impurities. When selecting a solvent, factors such as compatibility with EVA should be considered, and the operation conditions should be reasonably determined to ensure the best effect.

Control of the Quality and Characteristics of Carbon Fibers

– Selection of Appropriate Carbon Fiber Specifications：

The diameter and length of carbon fibers affect dispersion. A smaller diameter and an appropriate shorter length are beneficial for dispersion, but being too small or too short will cause problems such as cost and impact on the reinforcement effect. Appropriate specifications should be selected according to the application scenario and performance requirements to balance dispersion and reinforcement performance.

– Ensuring the Quality Stability of Carbon Fibers：

The production process of carbon fibers is complex, and quality fluctuations will affect the uniformity of dispersion. Manufacturers should strictly control each process and use detection methods to ensure quality standards so that each batch of carbon fibers meets the requirements and guarantees good and stable dispersion in EVA.

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