The curing of zinc silicate involves moisture from the atmosphere and is initiated by a reaction between polysilicic
acid and metallic zinc, in which the major part of the metallic zinc, which has not reacted, is surrounded by an insoluble matrix of zinc silicate.
Since aqueous sodium metasilicate solutions normally contain water, which is not compatible with thermoplastic polyurethane (TPU), a modified approach is adopted to extract polysilicic acid derived from aqueous metasilicate solution.
The polysilicic acid particles sizes in the THF solution were investigated using dynamic light scattering measurement.
While the silica was prepared through the polysilicic acid condensation through sodium metasilicate and hydrochloride ion exchanges, the average particle size was about 32 nm for the system without extraction.