掺TiO2玻璃粉对玻璃离子水门汀性能的影响

Effect of Glass Powder Added with TiO2 on Properties of Glass Ionomer Cement

采用不同TiO2掺杂量(0、0.5%、1%、3%和5%)制备的玻璃粉与聚丙烯酸制得玻璃离子水门汀(GIC),以及将含3%TiO2玻璃粉经不同温度(400℃、500℃、600℃和700℃)热处理后制得玻璃离子水门汀,测试GIC的固化时间和抗压强度。并使用DSC、XRD、SEM以及粒径分析仪,研究玻璃粉体热处理前后的结晶特性、玻璃转变和结构特征。结果表明,晶核剂TiO2的掺入使玻璃的结构致密性增强,不仅延长了玻璃离子水门汀的固化时间,而且明显提高GIC的抗压强度;热处理后的玻璃粉会发生团聚和结块现象,600℃以上时会有CaF2晶体析出。此外,玻璃粉经热处理后可以明显延长GIC的固化时间,然而过高温度的热处理改变玻璃颗粒表面形态,降低GIC的机械强度。

Glass ionomer cement (GIC) was prepared by using glass powders doped by different amount of TiO2 (0,0.5%,1%,3% and 5%) and polyacrylic acid,and powders containing 3% TiO2 was used to make glass ionomer cement after heating treatment by different temperature (400 ℃,500 ℃,600 ℃ and 700 ℃). Setting time and compressive strength of the GIC was tested. Besides,using DSC,XRD,SEM and particle size analyzer,the crystallization,glass transformation and structural characteristics of glass powder before and after thermal treatment were studied. The results show that the incorporation of crystal nucleating agent TiO2 enhances the compactness of glass structure,it not only prolonges the setting of glass ionomer cement,but also significantly increases the compressive strength of GIC. Glass beads reunion phenomenon happens after heat treatment,with the generating of CaF 2 crystal above 600 ℃. In addition,the setting time of GIC can be significantly prolonged after the treatment of glass powder. However,the higher heat treatment temperature will change the surface morphology of glass particles and reduce the mechanical strength of GIC seriously.