镁离子掺杂羟基磷灰石晶须的制备及热稳定性研究

Preparation and Thermal Stability of Magnesium Doped Hydroxyapatite Whiskers

羟基磷灰石(HA)是一种性能优良的骨替代材料,镁离子掺杂HA(Mg-HA)晶须不仅可以改变HA的生物学性能,还能起到增强作用。但Mg^(2+)掺入后会改变HA的晶格结构并影响它的热稳定性。采用水热合成法制备了镁离子掺杂HA晶须,并通过XRD、FTIR和SEM研究了镁离子掺杂HA的晶体结构、热稳定性及影响因素。结果表明:当镁离子掺杂量≤5%时,随着镁离子掺杂量的增加,HA晶须的结晶度降低,晶胞参数a基本不变、c值有所降低;当镁离子的掺量增加至8%时,有少量Ca_7Mg_2P_6O_(24)杂质峰出现。镁离子掺杂HA在800℃下就能发生分解,生成HA/β-TCP双相磷酸钙。镁离子的掺杂量、煅烧温度和生物玻璃添加量都能促进HA的分解。

Hydroxyapatite（ HA） is an excellent bone substitute materials. Magnesium doped HA（ MgHA） whiskers can not noly enhance the biological properties of HA,also be used as reinforcement for biomedical materials. However,incorporation of Mg^（2 ＋） into HA would change the crystal structure and affect their thermal stability. Thus,Mg-HA whiskers were prepared by a hydrothermal synthesis method,and their crystal structure,thermal stability and the influencing factors of the Mg-HA whiskers were studied by XRD,FTIR and SEM. The results show that the crystallinity of HA decrease with the increase of magnesium ion doping content when the magnesium ion doping content is less than 5%,and the cell parameters a is basically unchanged,and c is gradually reduced. When magnesium ion doping increase to 8%,a small amount of impurity peaks assign as Ca_7Mg_2P_6O_（24） appear. Mg-HA would decompose at 800℃, forming HA/β-TCP bipasic calcium phosphate. Magnesium ion doping content, calcination temperature and bioglass addition are found significantly to enhance the decomposition of HA.