New applications of alginates in the shape forming of ceramics

作者：Santacruz I^*; Nieto I; Moreno R

来源：Boletin de la Sociedad Espanola de Ceramica y Vidrio, 2005, 44(1): 45-52.

• processing
• shaping
• suspensions
• processing additives
• chemical gelation
• alginates

Alginates are naturally occurring polysaccharides frequently used as temporary binders in ceramic processing. However, behind their thickenning behaviour, alginates have interesting gelling properties. This function has not been exploited in ceramics, although it is receiving increased attention because of the versatility facing new shaping routes for manufacturing bulk pieces and, in particular, films and coatings. This work reviews the near-net shaping of ceramics through chemical gelation, among which two groups of techniques can be distinguished: those using monomers that polymerize by means of initiators/catalysts, and those using high molecular weight polysaccharides that develop a network structure by means of cations present in the medium. The last case is reviewed in this work, which presents the basis of the chemistry of alginates, focusing their structure and the gelation mechanism, and explores the viability of alginate gelation in the manufacture of thick films by tape casting on the basis of the processing parameters.

• 出版日期2005-2