Fillerstoffer

Fillerstoffer are inert or semi-inert particles added to a base material to occupy volume, modify properties and reduce cost. They are used across industries such as plastics, composites, concrete, ceramics, paper, cosmetics and dentistry. The choice of filler depends on the desired effect, the matrix, processing method and economic considerations.

Common inorganic fillers include calcium carbonate, silica, talc, wollastonite, clay minerals and fly ash; organic fillers include cellulose fibers and natural polymers. Nanofillers such as silica or carbon nanotubes are used for advanced property enhancement. Fillers vary in size, shape and surface chemistry, which influences dispersion and bonding with the host material.

Functions of fillers include increasing stiffness and hardness, reducing shrinkage and thermal expansion, improving dimensional stability, altering viscosity and processing behavior, improving opacity or radiopacity, and lowering material costs. In concrete, supplementary cementitious materials like fly ash or slag act as fillers and reactions enhancers. In polymers, surface-treated fillers often bond better with the matrix.

Key considerations when selecting fillers are particle size and distribution, loading fraction, surface treatment, and compatibility with the matrix. The processing method, mixing, and potential effects on strength, toughness and durability must be evaluated. Environmental and health aspects include dust generation during handling and the inert nature of many fillers, though some may pose exposure risks.

Fillerstoffer are a broad category encompassing many materials and applications. They enable cost savings and tailored properties, but excessive loading or poor dispersion can degrade performance. Advances in surface modification and nano-fillers continue to expand their role in modern materials.