lignosulfonate has different compositions and molecular dimensions (because they are polymers that can be modified by the addition of organic or inorganic groups to the molecule).
They are anionic derivatives of lignosulfonate , water soluble and surfactants. lignosulfonate s can increase mechanical green and dry strength in ceramic pieces. Also, they work as lubricants during extrusion or pressing . Additions of lignosulfonate s to ceramic slips can vary from 0.1 to 2.0% and they are relatively inexpensive. For pressed tiles, 1% lignosulfonate can double mechanical strength (however often a black core appears). lignosulfonate s are often used to reduce shrinkage yet maintain after-forming mechanical strength (because reduced amounts of plastic clays are needed).
Currently in building ceramic body used in the formulation additives are mainly two: one is body enhancer , mainly used to increase the strength of the body , is mainly used in low viscosity carboxymethylcellulose is CMC; a coagulant solution species are primarily used to reduce the viscosity of the mud , reducing the moisture content of the mud to reduce the spray drying tower granulation step water slurry fuel consumption , is used in ceramic manufacturers coagulant solution of sodium silicate and the three main sodium tripolyphosphate.
potential applications and benefits of using lignosulfonate in architectural ceramics:
- As a plasticizer – It improves the workability and flexibility of ceramic slips and bodies during shaping processes like casting, slip trailing, pressing. This allows complex shapes.
- Water retention – Lignosulfonate reduces the rate of drying in wet bodies and cast pieces, preventing cracking due to uneven shrinkage.
- Binding agent – It enhances cohesion between ceramic powders and particles in dry-pressed bodies through electrostatic interactions.
- Additive for tiles/pavers – Imparts surface washability, improved abrasion resistance and reduced efflorescence in fired products when used at 0.05-0.2% levels.
- Modifier for glazes – Acts as a levigating and dispersing agent for glaze constituents, promoting smoothness and uniformity of applied glaze coats.
- Porosity controller – Influences pore size and density in fired ceramics depending on content, affecting physical, thermal and acoustic properties.
- Economical – Being plant-derived and low-cost, lignosulfonate provides sustainable advantages over synthetic additives.
- Environmental – Lignosulfonate use may reduce water usage and CO2 emissions in ceramic manufacturing processes versus alternatives.