Micronized sodium metasilicate, also known as microfine sodium metasilicate or micronized water glass, is a finely powdered form of sodium metasilicate (Na2SiO3). In polymer applications, micronized sodium metasilicate can serve several purposes:
Alkaline pH Adjustment
Sodium metasilicate is an alkaline compound and can be used to adjust the pH of polymer solutions or emulsions. Controlling pH is crucial in polymerization processes to ensure optimal conditions for the reaction to occur. Micronized sodium metasilicate provides a finely divided form that facilitates rapid dissolution and uniform pH adjustment.
Anti-corrosion Agent
Sodium metasilicate can provide corrosion protection to metal surfaces when incorporated into polymer coatings or formulations. It forms a protective film that inhibits the interaction between the metal substrate and corrosive environments, thereby extending the lifespan of coated components.
Reinforcement
Sodium metasilicate can serve as a reinforcing filler in polymer composites, contributing to improvements in mechanical properties such as tensile strength, modulus, and impact resistance. Its fine particle size and high aspect ratio facilitate uniform dispersion and strong interfacial adhesion within the polymer matrix.
Viscosity Control
Sodium metasilicate can influence the viscosity of polymer solutions or melts when added in appropriate amounts. This property can be utilized to control the flow behaviour of polymer melts during processing, improving processability and enhancing the final product’s characteristics.
Flame Retardancy
While sodium metasilicate itself is not a flame retardant, it can contribute to flame retardancy indirectly by promoting char formation and thermal stability in polymer formulations. This can help inhibit the spread of flames and reduce the release of flammable gases during combustion.