NMR study of crystallization in MgO–CaO–SiO2–P2O5 glass-ceramics

29Si and 31P magic-angle-spinning (MAS) nuclear magnetic resonance (NMR) measurements were employed to investigate crystallization in MgO–CaO–SiO2–P2O5 bioglass-ceramics. The results suggest that wollastonite (β-CaSiO3) is separated as a new crystalline phase, corresponding to the appearance of a sharp signal in the 29Si MAS NMR spectra, while oxyapatite (Ca10(PO4)6O) forms in the process of the order of the phosphorus-rich phases increasing as a whole, corresponding to the gradual narrowing of 31P MAS NMR spectra. ZnO can make the glass stable and difficult to crystallize at a low temperature, while at a high temperature, ZnO can participate in the crystallization of β-CaSiO3 and promote it.