锌掺杂的羟基磷灰石复合物（聚乳酸或石墨烯）制备与模拟研究
发布时间：2019-05-27 04:34
【摘要】：人工合成的锌掺杂羟基磷灰石(ZnHA)具有良好的生物亲和性、生物相容性、生物活性和骨传导作用,可作为一种优良的硬组织替代材料,但是由于其具有陶瓷材料固有的断裂韧性低、脆性高和抗疲劳强度差等缺点限制了其临床应用。因此必须在ZnHA中加入第二相或多相以增强其的力学性能。本论文就ZnHA分别与聚乳酸(PLA)、石墨烯(GP)复合物的制备以及采用第一性原理对ZnHA晶体结构和弹性性能进行研究,通过X射线衍射(XRD)、傅里叶变换红外光谱(FTIR)、场发射扫描电子显微镜(FESEM)、X射线能量色散仪(EDX)、X射线光电子能谱(XPS)、透射电镜(TEM)和拉曼光谱仪(Raman)等测试手段,对所制备的样品进行分析和研究。通过湿化学法制备不同摩尔分数的ZnHA粉体,采用旋涂法在不锈钢304基体上制备锌掺杂羟基磷灰石/聚乳酸(ZnHA/PLA)的复合涂层,研究在600℃烧结后不同含锌量对ZnHA/PLA复合涂层成分及形貌的影响。研究表明:锌离子成功进入HA晶格中,所制备的HA纳米颗粒显示出棒状形态,而Zn离子的取代抑制了HA晶体生长并减小了其尺寸。ZnHA/PLA复合涂层经600℃烧结后其表面形貌呈现出均匀、多孔结构,厚度为60μm左右。PLA复合涂层中的引入不改变HA的物相组成,且可防止高温热处理时基底引起HA的分解。采用一锅水热处理原位合成锌掺杂羟基磷灰石/石墨烯(ZnHA/GP)复合材料。研究不同Zn掺杂量对复合材料中HA的微观形貌的影响,初步探讨引入Zn离子对HA晶体结构以及对复合材料界面相互作用的影响。微观形貌表明,HA颗粒由平均长度约75nm和直径约25nm的棒状聚集组成,且紧密附着在石墨烯表面上,而随着Zn掺杂量的增加,附着在GP表面上的ZnHA的量逐渐减少,且Zn掺杂量达到20mol%时,晶粒呈现出无定形相,这表明在石墨烯表面上低结晶度的ZnHA晶粒削弱其与GP之间的界面相互作用。最后,采用第一性原理分别计算HA、缺钙HA和Zn HA的弹性模量,分析Zn掺入对HA晶体的弹性性能的影响;结合实验数据分析,研究Zn掺入对HA晶体结构的影响。计算结果表明Zn的掺入会使得HA晶体的整体结构软化,弹性性能有所下降。但是与缺陷HA相比,ZnHA仍旧具有较好的稳定性与弹性性能。ZnHA晶体结构计算结合FTIR、XRD分析可知Zn离子的掺入导致了羟基(OH-)往Zn离子漂移,与磷酸根(PO_4~(3-))的距离更近,可能导致氢键的形成。
[Abstract]:The synthesized zinc-doped hydroxyapatite (ZnHA) has good biological affinity, biocompatibility, biological activity and bone conduction, and can be used as an excellent hard tissue substitute material. However, its clinical application is limited by its inherent low fracture toughness, high brittleness and poor fatigue strength. Therefore, the second phase or multiphase must be added to ZnHA to enhance its mechanical properties. In this paper, the preparation of ZnHA and polylactic acid (PLA), graphene (GP) composites and the first principle study on the crystal structure and elastic properties of ZnHA were studied. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR),) was used to study the crystal structure and elastic properties of ZnHA. The samples were analyzed and studied by field emission scanning electron microscope (FESEM), X-ray energy dispersive instrument (EDX), X-ray photoelectron spectroscopy (XPS), transmission electron microscope (TEM) and Raman spectrometer (Raman). ZnHA powder with different mole fraction was prepared by wet chemical method, and zinc-doped hydroxyapatite / polylactic acid (ZnHA/PLA) composite coating was prepared on stainless steel 304 substrate by spin coating method. The effect of different zinc content on the composition and morphology of ZnHA/PLA composite coating after sintering at 600 鈩，
本文编号：2485905
[Abstract]:The synthesized zinc-doped hydroxyapatite (ZnHA) has good biological affinity, biocompatibility, biological activity and bone conduction, and can be used as an excellent hard tissue substitute material. However, its clinical application is limited by its inherent low fracture toughness, high brittleness and poor fatigue strength. Therefore, the second phase or multiphase must be added to ZnHA to enhance its mechanical properties. In this paper, the preparation of ZnHA and polylactic acid (PLA), graphene (GP) composites and the first principle study on the crystal structure and elastic properties of ZnHA were studied. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR),) was used to study the crystal structure and elastic properties of ZnHA. The samples were analyzed and studied by field emission scanning electron microscope (FESEM), X-ray energy dispersive instrument (EDX), X-ray photoelectron spectroscopy (XPS), transmission electron microscope (TEM) and Raman spectrometer (Raman). ZnHA powder with different mole fraction was prepared by wet chemical method, and zinc-doped hydroxyapatite / polylactic acid (ZnHA/PLA) composite coating was prepared on stainless steel 304 substrate by spin coating method. The effect of different zinc content on the composition and morphology of ZnHA/PLA composite coating after sintering at 600 鈩，
本文编号：2485905
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