摘要
以Ca(NO3) 2 ·4H2 O和Na2 SiO3·9H2 O为原料 ,聚乙二醇为分散剂 ,采用化学沉淀方法制备了直径 4 0nm的无定型纳米硅酸钙粉末 ,80 0℃热处理后得到平均直径 10 0nm的 β 硅灰石粉末。把两种粉末压制成块浸泡在模拟体液中 ,研究了两种粉体在模拟体液中的生物活性行为。结果表明 :由于无定型硅酸钙具有比β 硅灰石小的颗粒尺寸 ,且处于亚稳态 ,Ca2 + 的活性较大 ,无定型硅酸钙具有比 β 硅灰石较高的生物活性。在无定型硅酸钙表面不仅沉积了羟基磷灰石 ,而且也沉积了碳酸钙 ,以致于在浸泡初期阶段阻止了羟基磷灰石的沉积。经长时间浸泡后 ,无定型硅酸钙和 β 硅灰石表面都能沉积一层羟基磷灰石。
Nano-sized amorphous CaSiO 3 (A-CS) and β-wollastonite (β-CS) powder were produced by chemical precipitation method and subsequent heat treatment, using Ca(NO 3) 2·4H 2O and Na 2SiO 3·9H 2O as the starting materials, polyethylene glycol as the dispersant. Bulk materials were produced using the two powders as precursors. The particle sizes of A-CS and β-CS are about 40nm and 100nm in diameter respectively. The bioactivities of A-CS and β-CS materials were investigated by soaking the two materials in SBF solution at 36.5℃ for 6 hours to 15 days. Experiment results revealed that the A-CS shows higher bioactivities than the β-wollastonite because the A-CS has a smaller particle size than the β-wollastonite and the Ca-O bond of A-CS is not as strong as that in β-wollastonite lattice. CaCO 3 crystallized accompanied with HAP on the A-CS surfaces and prohibited the crystallization of HAP at early stage of soaking. After long soaking time, both A-CS and β-wollastonite could develop a HAP layer.
出处
《材料科学与工程学报》
CAS
CSCD
北大核心
2005年第2期230-234,共5页
Journal of Materials Science and Engineering
关键词
硅酸钙
纳米粉体
化学沉淀法
生物活性
calcium silicate
nanopowder
chemical precipitation method
bioactivity
