Evolution of the Formation of Inorganic Polymers in the CaO—SiO2—P2O5 System Using Metal Alkoxides

Inorganic polymers provide structural integrity to cements. The CaO—SiO₂—P₂O₅ system has not been studied extensively, but it is important to both cementitious and biological systems. The hydrolytic decomposition of homogeneous mixtures of tetraethyl orthosilicate and calcium isopropoxide with additions of anhydrous phosphoric acid in isopropyl alcohol was used to evaluate the formation of inorganic polymers. XRD, DTA, and TGA were used to characterize the decomposition products. The formation of inorganic polymers at room temperature and pressure was used as a criterion to establish cement-forming compositions within the CaO—SiO₂—P₂O₅ system.