Work

Composite Materials Based on Sodium Alginate and Synthetic Powders of Calcium Carbonate

Year: 2026

Type: article

Abstract: Composite materials in form of granules, networks and films were created from sus-pensions of synthetic powders of calcium carbonates CaCO3 in aqueous solutions of sodium alginate. Powders of calcium carbonates CaCO3 were synthesized from 0.5M aqueous solutions of calcium chloride CaCl2 and aqueous solutions of potassium K2CO3 (at molar ratio Ca/CO3=1), sodium Na2CO3 (at molar ratio Ca/CO3=1), ammonium (NH4)2CO3 (at molar ratios Ca/CO3=1 and Ca/CO3=0.5) carbonates. Phase composition of powder synthesized from CaCl2 and K2CO3 was presented by calcite. Phase compo-sition of powders synthesized from other soluble carbonates included calcite and va-terite. The powder preparation protocol excluded the stage of by-product removing via synthesized powder washing providing their preservation at very low level. Presence of NH4Cl as reaction by-product even in small quantities can be taken as a reason vis-ually observed subsequences of cross-linking reaction at the stage of suspensions preparation. Aqueous solution of sodium alginate and suspensions containing powders synthesized from potassium K2CO3 and sodium Na2CO3 carbonates demonstrated the similar dependence of viscosities from share rate. Presence of (NH4)2CO3 in the powder synthesized at molar ratio Ca/CO3=0.5 was the reason of the lower viscosity of the suspension in comparison with suspensions loaded with powders containing KCl, NaCl and (NH4)2Cl as reaction by-products due to decomposition of unstable (NH4)2CO3 and gas phase formation. Presence of (NH4)2Cl in the powder synthesized at molar ratio Ca/CO3=1 in contrary was a reason of the highest viscosity suspension comparison with those under investigation. Granules, meshes and films were created via interaction of suspensions calcium carbonates CaCO3 in aqueous solutions of so-dium alginate with 0.25M aqueous solutions of calcium chloride CaCl2 to provide formation of matrix of composites via Ca-crosslinking of sodium alginate followed by washing and freeze drying under deep vacuum. Created composite materials in form of granules, meshes and films based on Ca-cross-linked alginate and powders of synthetic calcium carbonate can be recommended for the skin wounds and bone defects treatment, and drug delivery carriers.

Source: Journal of Composites Science

DOI: 10.3390/jcs10030172