Fyllstoff

Fyllstoff is a substance added to a base material to occupy space and modify its properties. Fillers are used to increase volume, reduce cost, adjust density, and influence processing characteristics. They are common in many industries, including plastics, rubber, paints and coatings, paper, cosmetics, foods, and building materials. While many fillers are relatively inert, they can be engineered to interact with the host matrix when needed.

Common filler types include inorganic minerals such as calcium carbonate, talc, kaolin, silica, and mica; organic fillers such as cellulose, starch, and wood flour; and newer nano- or surface-modified fillers designed to improve dispersion and bonding. Fillers may be used alone or in combination, and their properties are chosen to fit the intended application and processing method.

Manufacturing and properties of fillers depend on particle size distribution, shape, loading level, and surface treatment. Surface modification, for example with silanes or other coupling agents, can improve compatibility with polymers, reduce moisture sensitivity, enhance dispersion, and tailor optical properties like opacity or brightness. The chosen filler and its surface treatment influence rheology, mechanical performance, thermal stability, and appearance.

Applications and considerations: in plastics and rubber, fillers help tailor stiffness, dimensional stability, and cost; in paints and coatings, they affect opacity, coverage, and texture; in paper, fillers influence bulk, whiteness, and printability. High filler loading can reduce strength, elongation, or impact resistance if dispersion is poor, so compatibility and processing are critical.

Safety and regulation: handling fillers may generate dust, so dust control and proper ventilation are important. Many fillers used in foods or cosmetics require regulatory approval and quality standards. Environmental and end-of-life considerations vary by filler type and use.