Modificação da superfície do pó involves treating the powder surface using physical, químico, or mechanical methods. The goal is to alter its physical and chemical properties or impart new functions. This meets the needs of modern materials, processes, and technologies. Understanding the role of surface modification and powder properties helps improve material performance. Controlling modifier quantity, choosing the right equipment and process enhances aplicação de pó. It can even give powders new functions or performance capabilities.
The role of modification
The role of powder surface modification varies by application. The main goal is to enhance powder performance or impart new functions. This meets the needs of new materials, technologies, and product development. Powder modification has five main functions:
- Transform inorganic fillers from simple additives to functional fillers.
- Provide new technologies for polymers and composite materials.
- Improve particle dispersion and prevent aggregation.
- Enhance the stability of powder materials and product performance.
- Improve environmental sustainability and economic production, increasing added value.
Powder raw material properties
The properties of powder materials mainly include acidity, alkalinity, surface structure, functional groups, adsorption, and chemical reactivity. Surface modifiers should chemically react or adsorb onto the powder surface whenever possible. Physical adsorption may desorb under strong stirring or extrusion in later applications. For example, silicate minerals like quartz, feldspar, mica, and kaolin can bond with silane coupling agents. This forms a strong chemical adsorption. However, silane coupling agents generally do not react or adsorb onto carbonate-based alkaline minerals. Titanates and aluminates, under certain conditions, can adsorb onto carbonate-based alkaline minerals. Thus, silane coupling agents are unsuitable for modifying carbonate-based alkaline minerals like light and heavy carbonato de cálcio.
Modifier dosage
The optimal amount of surface modifier for monolayer adsorption on particles depends on the specific surface area of the powder and the molecular cross-sectional area of the modifier. However, this amount may not correspond to 100% coverage of the surface modifier. For inorganic surface revestimento modification, different coating rates and layer thicknesses can exhibit varied characteristics, such as color and gloss. Therefore, the actual optimal amount should be determined through modification and performance tests. This is because the amount of modifier is related to both the dispersion and uniformity of coating during surface modification. It also depends on the specific requirements of the application system for the surface properties and technical specifications of the powder.
Modification process
Once the surface modifier amount and formulation are determined, the surface modification process is one of the key factors influencing the effect. The process must meet the application requirements or conditions of the surface modifier. It should ensure good dispersion of the modifier and achieve uniform and strong coating on the powder surface. At the same time, the process should be simple, with controllable parameters, stable product quality, low energy consumption, and minimal pollution.
Modification equipment
Moinho turbo para revestimento em pó
Poderoso campo de fluxo de vórtice, moagem instantânea e revestimento
O rotor cônico e o estator são adotados e a folga entre o rotor e o estator pode ser ajustada; no poderoso campo de fluxo de vórtice, a velocidade linear do rotor pode chegar a 120 m/s, o que é especialmente adequado para a dispersão, redução e britagem de materiais aglomerados. O material é impactado, cisalhado e friccionado em alta velocidade entre o rotor e o estator para completar o processo de retificação e revestimento.
Este sistema de revestimento de superfície em pó contínuo foi projetado com base no know-how alemão com equipamentos chineses e pode ser usado para revestimento de vários pós como carbonato de cálcio (GCC, PCC), caulim, talco, mica, grafite, sulfato de bário, negro de fumo branco, magnesium hydrate, zinc oxide, aluminum oxide, and is suitable for a variety of solid/liquid coating agents, like aluminate coupling agent, titanate coupling agent, silane coupling agent and stearic acid. Coating machine consists of three units of mixing rooms. High-speed rotation creates great vortex flow inside these special-shaped rooms. Powder and coating agent are mixed in the high-speed gas-solid vortex flows.
Coating machine with both surface coating and particle dispersing functions is suitable for various powders with different fineness, and has a unique coating effect for the materials with small apparent specific gravity and high volume to weight ratio. Automatic temperature control system ensures stable high temperature for coating agent melting into liquid and mixing with uncoated powder. Heating and cooling of powder and coating agent are completed in one machine, which does not need independent cooling system. High utilization ratio of coating agent, high powder-coated rate, high activation grade, low energy consumption, and very few agglomerates in final coated product. The whole system is operated under negative pressure, no dust emission, and low labor intensity.
Moinho de três rolos para revestimento em pó
Revestimento the powder surface by changing the cyclone vortex According to different materials and application industries, the production capacity and tamanho da partícula range will be different. Please contact our engineers to customize the equipment for you. Our experts will contact you within 6 hours to discuss your needs for machine and processes.
Este sistema de revestimento de superfície em pó contínuo foi projetado com base no know-how alemão com equipamentos chineses e pode ser usado para revestimento de vários pós como carbonato de cálcio (GCC, PCC), caulim, talco, mica, grafite, sulfato de bário, negro de fumo branco, magnesium hydrate, zinc oxide, aluminum oxide, and is suitable for a variety of solid/liquid coating agents, like aluminate coupling agent, titanate coupling agent, silane coupling agent and stearic acid. Coating machine consists of three units of mixing rooms. High-speed rotation creates great vortex flow inside these special-shaped rooms. Powder and coating agent are mixed in the high-speed gas-solid vortex flows.
Coating machine with both surface coating and particle dispersing functions is suitable for various powders with different fineness, and has a unique coating effect for the materials with small apparent specific gravity and high volume to weight ratio. Automatic temperature control system ensures stable high temperature for coating agent melting into liquid and mixing with uncoated powder. Heating and cooling of powder and coating agent are completed in one machine, which does not need independent cooling system. High utilization ratio of coating agent, high powder-coated rate, high activation grade, low energy consumption, and very few agglomerates in final coated product. The whole system is operated under negative pressure, no dust emission, and low labor intensity.
Pin Mill for Powder Coating
Pin type crushing disc, no screen structure, fast speed, large capacity and low heat generation. Single power or double power can be selected, the line speed can reach up to 240m/s, strong impact force and shear force, and the product tamanho da partícula is fine. It is suitable for dispersing and deagglomerating It is suitable for continuous high-speed mixing for ultrafine powder and liquid, and particle surface revestimento modification. It can be equipped with an classificador de ar to control the product fineness. Compact in structure, the mill is extremely easy to disassemble and clean.
Conclusão
In conclusion, powder surface modification technology plays a crucial role in enhancing the properties and performance of powders for various industrial applications. By selecting the right modifiers and optimizing the modification process, it is possible to achieve improved dispersion, stability, and functionality, meeting the demands of modern materials and technologies. As innovation continues, surface modification will remain a key factor in advancing new materials and enhancing product performance.
Pó épico
Epic Powder, com mais de 20 anos de experiência na indústria de pós ultrafinos. Promovemos ativamente o desenvolvimento futuro de pós ultrafinos, com foco nos processos de britagem, moagem, classificação e modificação de pós ultrafinos. Entre em contato conosco para uma consulta gratuita e soluções personalizadas! Nossa equipe de especialistas se dedica a fornecer produtos e serviços de alta qualidade para maximizar o valor do seu processamento de pós. Epic Powder — Seu especialista confiável em processamento de pós!