【摘要】：人工合成的鋅摻雜羥基磷灰石(ZnHA)具有良好的生物親和性、生物相容性、生物活性和骨傳導(dǎo)作用,可作為一種優(yōu)良的硬組織替代材料,但是由于其具有陶瓷材料固有的斷裂韌性低、脆性高和抗疲勞強(qiáng)度差等缺點(diǎn)限制了其臨床應(yīng)用。因此必須在ZnHA中加入第二相或多相以增強(qiáng)其的力學(xué)性能。本論文就ZnHA分別與聚乳酸(PLA)、石墨烯(GP)復(fù)合物的制備以及采用第一性原理對(duì)ZnHA晶體結(jié)構(gòu)和彈性性能進(jìn)行研究,通過(guò)X射線衍射(XRD)、傅里葉變換紅外光譜(FTIR)、場(chǎng)發(fā)射掃描電子顯微鏡(FESEM)、X射線能量色散儀(EDX)、X射線光電子能譜(XPS)、透射電鏡(TEM)和拉曼光譜儀(Raman)等測(cè)試手段,對(duì)所制備的樣品進(jìn)行分析和研究。通過(guò)濕化學(xué)法制備不同摩爾分?jǐn)?shù)的ZnHA粉體,采用旋涂法在不銹鋼304基體上制備鋅摻雜羥基磷灰石/聚乳酸(ZnHA/PLA)的復(fù)合涂層,研究在600℃燒結(jié)后不同含鋅量對(duì)ZnHA/PLA復(fù)合涂層成分及形貌的影響。研究表明:鋅離子成功進(jìn)入HA晶格中,所制備的HA納米顆粒顯示出棒狀形態(tài),而Zn離子的取代抑制了HA晶體生長(zhǎng)并減小了其尺寸。ZnHA/PLA復(fù)合涂層經(jīng)600℃燒結(jié)后其表面形貌呈現(xiàn)出均勻、多孔結(jié)構(gòu),厚度為60μm左右。PLA復(fù)合涂層中的引入不改變HA的物相組成,且可防止高溫?zé)崽幚頃r(shí)基底引起HA的分解。采用一鍋水熱處理原位合成鋅摻雜羥基磷灰石/石墨烯(ZnHA/GP)復(fù)合材料。研究不同Zn摻雜量對(duì)復(fù)合材料中HA的微觀形貌的影響,初步探討引入Zn離子對(duì)HA晶體結(jié)構(gòu)以及對(duì)復(fù)合材料界面相互作用的影響。微觀形貌表明,HA顆粒由平均長(zhǎng)度約75nm和直徑約25nm的棒狀聚集組成,且緊密附著在石墨烯表面上,而隨著Zn摻雜量的增加,附著在GP表面上的ZnHA的量逐漸減少,且Zn摻雜量達(dá)到20mol%時(shí),晶粒呈現(xiàn)出無(wú)定形相,這表明在石墨烯表面上低結(jié)晶度的ZnHA晶粒削弱其與GP之間的界面相互作用。最后,采用第一性原理分別計(jì)算HA、缺鈣HA和Zn HA的彈性模量,分析Zn摻入對(duì)HA晶體的彈性性能的影響;結(jié)合實(shí)驗(yàn)數(shù)據(jù)分析,研究Zn摻入對(duì)HA晶體結(jié)構(gòu)的影響。計(jì)算結(jié)果表明Zn的摻入會(huì)使得HA晶體的整體結(jié)構(gòu)軟化,彈性性能有所下降。但是與缺陷HA相比,ZnHA仍舊具有較好的穩(wěn)定性與彈性性能。ZnHA晶體結(jié)構(gòu)計(jì)算結(jié)合FTIR、XRD分析可知Zn離子的摻入導(dǎo)致了羥基(OH-)往Zn離子漂移,與磷酸根(PO_4~(3-))的距離更近,可能導(dǎo)致氫鍵的形成。
[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，

本文編號(hào)：2485905