SETTING ACCELERATORS Short setting times are often required during the use of cement-bonded mastics. The use of a setting accelerator in cement-containing mastics allows the creation of a lattice of hardly soluble silicate compounds. This gives the components sufficient strength before the cement bond develops its full potential.
Short setting times are often required during the use of cement-bonded mastics. The use of a setting accelerator in cement-containing mastics allows the creation of a lattice of hardly soluble silicate compounds. This gives the components sufficient strength before the cement bond develops its full potential.
Chemical binders are applied in refractory bodies to reduce or even replace hydraulic binding agents. These alternative binders allow a compaction of refractory mastics. After drying, these mastics can be heated faster than hydraulically bonded bodies.
Biocides are required for the application of organic additives and/or raw materials to counteract their deterioration caused by micro organisms such as bacteria, yeasts or fungi, and consequently to guarantee long-term stability.
Wetting agents permit the introduction and dispersion of hydrophobic raw materials in refractory bodies (e.g. soot and graphite). Wetting agents are surface-active preparations exhibiting high surface affinity, which in turn decreases the surface tension of the preparation water.
On account of their swelling capacity, plasticisers increase the plasticity of non-plastic raw materials, which makes it possible to avoid the addition of clay as a plasticiser. Thus, the resistance to temperature variations and the hot strength of refractory pressing, ramming and extrusion bodies can be improved.
Temporary binders bring about an increase in green and dry breaking strength through the formation of adhesive forces. This leads to an increase in edge strength, which in turn is required for the easier handling of the shaped parts during the technological processes that follow and for the internal transport. The use of temporary binders allows a reduction or even the complete replacement of the clay proportion in refractory bodies. This leads to improved properties of the batch at high temperatures. The target result is the reduction in drying sensitivity.
In ceramic mastics containing water glass, the use of a hardener for water glass, which hydrolyses in the alkaline environment, allows the controlled precipitation of silicic acid, leading to a defined hardening of the body.
