Additive / Fillers

What types of additives and fillers are there?

Additives and fillers are essential components in epoxy resin systems, each offering unique advantages and properties depending on the application.

> Additives include liquid foaming agents, specifically designed for foam laminates or sandwich structures. Liquid thickeners are used for targeted thixotropy, significantly improving anti-sagging and settling behavior. Air release agents reduce foam and bubble formation during processing, while bubble-free atomizers eliminate surface bubbles in casting resins or epoxy coatings. Flow agents enhance the flow behavior, ensuring a smooth surface. Light stabilizers improve UV resistance and prevent material degradation from sunlight. Reactive diluents provide excellent dilution performance for epoxy resins.

> Fillers are insoluble materials with diverse applications: glass fiber chips increase tensile, compressive, and flexural strength, and reinforce adhesive joints and molding compounds. They are also a sustainable alternative to asbestos. Cotton flakes serve as thickeners for viscosity control, improve impact strength, and are easy to sand. In combination with glass fibers, they enhance mechanical strength. Thixotropic agents prevent particle settling, enabling self-leveling flooring or non-sag coatings and adhesive beads. Microballoons, hollow glass spheres, help produce lightweight, compression-resistant, and low-shrinkage fillers while maintaining good flowability. Aluminum powder prevents sagging on sloped surfaces, increases compressive strength, and is ideal for model-making boards. Quartz sand is used in polymer mortars, for surface scattering, and to imitate mineral substrates visually.
 

What are the characteristics of additives?

Additives are soluble agents added in small quantities to epoxy resin systems to improve mechanical, chemical, and processing characteristics. Typical additives include liquid foaming agents for foam laminates, sandwich elements, and lightweight components. Liquid thickeners improve anti-sagging and settling resistance through thixotropy, enhancing both processing quality and surface finish. Special air release agents minimize foam and bubble formation in casting resins and coatings, while bubble-free atomizers destroy surface bubbles in coatings and laminates. Other additives like flow agents ensure even, bubble-free application. Light stabilizers increase UV stability and extend the lifespan of resin systems. Reactive diluents provide excellent dilution properties and help reduce viscosity, especially for epoxy resins. Together, these additives significantly enhance processing and product performance across tooling, model-making, and industrial production.

How do fillers improve mechanical properties?

Fillers are insoluble substances added to resin matrices to specifically improve mechanical and electrical performance. High-quality glass fiber chips enhance tensile, compressive, and flexural strengths while maintaining flowability, making them ideal for reinforcing joints, adhesives, and molding compounds—often used as a safe alternative to asbestos. Cotton flakes act as effective thickeners for viscosity adjustment, boost impact resistance, and improve strength values. They are easily sanded and can be combined with glass fibers for additional synergy. Ultra-fine microballoons, made from glass or plastic, are used in lightweight fillers, offering compressive strength, non-flammability, and low shrinkage, with excellent flow characteristics due to their spherical shape. Other fillers like aluminum powder prevent sagging on inclines, increase compressive resistance, and are suited for model board fabrication. Quartz sand is widely used for surface scattering, polymer mortar production, and the visual replication of mineral surfaces, playing a key role in surface finishing.

What are the practical benefits of additives and fillers?

The targeted combination of additives and fillers allows for precise, flexible adjustment of epoxy systems to meet specific technical demands. Additives enhance workability, reduce bubble formation, and optimize flow, allowing the production of high-quality composites, foam laminates, and coating systems. At the same time, fillers increase mechanical strength, enable viscosity control, and boost the durability of materials. Fillers such as glass fibers and cotton flakes are ideal for reinforcing joints, molding compounds, and laminates, while microballoons create lightweight, compression-resistant, and non-flammable masses highly valued in model construction and lightweight engineering. The use of aluminum powder and quartz sand extends the applications to model boards and decorative surfaces, including polymer mortars. This versatility and customizability make additives and fillers indispensable in industrial manufacturing, tooling, and advanced composite production.