【摘要】：本論文針對(duì)目前制備多孔磷酸鈣骨修復(fù)材料在成型方法和性能上存在的不足,首次采用擠出成型法,利用自合成β-磷酸三鈣(β-TCP)粉體制備了蜂窩狀多孔β-TCP骨修復(fù)材料。通過(guò)添加造孔劑對(duì)擠出制備的多孔材料的孔壁進(jìn)行了造孔,形成出具有宏孔(擠出成型孔)、微米孔(排除造孔劑顆粒形成的孔)和亞微米孔(燒結(jié)孔)的三級(jí)孔磷酸鈣陶瓷骨修復(fù)材料,并通過(guò)在β-TCP合成過(guò)程中同步引入焦磷酸鈣改善多孔β-TCP陶瓷的強(qiáng)度,通過(guò)灌注技術(shù)調(diào)節(jié)擠出宏孔的尺寸和形狀,制備出了同時(shí)具有高孔隙率、單向連通、孔徑可控、孔徑均勻、抗壓強(qiáng)度較高的多級(jí)孔磷酸鈣骨修復(fù)材料。 首先,設(shè)計(jì)了合適的擠出成型模具,采用活塞式液壓擠出成型方法,制備具有孔徑可調(diào)、孔徑均勻、開(kāi)口孔率高、力學(xué)性能好、適合工業(yè)化生產(chǎn)等優(yōu)點(diǎn)的多孔支架。采用濕式粉碎法合成β-TCP、CPP/β-TCP粉體,研究了β-TCP和CPP/β-TCP粉體的可成型性。實(shí)驗(yàn)表明:所合成的β-TCP和CPP/β-TCP粉體都適用于采用擠出成型。將粉體和各添加劑按照一定的順序進(jìn)行混煉,得到可塑性好的泥團(tuán)。采用正交試驗(yàn)法,得出了在β-TCP粉體成型過(guò)程中各添加劑的最佳配比為甲基纖維素M450 8%、液體石蠟10 %和去離子水32 %。并對(duì)影響擠出多孔材料結(jié)構(gòu)和性能的因素,包括擠出壓力、干燥制度、燒成制度、模具結(jié)構(gòu)等進(jìn)行了實(shí)驗(yàn)分析,通過(guò)實(shí)驗(yàn)確定了較合理的工藝參數(shù)。所制備的蜂窩狀多孔β-TCP骨修復(fù)材料具有較理想的結(jié)構(gòu)和性能。擠出成型的多孔材料,擠出孔呈方形,孔徑基本一致,約為850μm,孔隙率約為74 %,抗壓強(qiáng)度約為17 MPa。 為了進(jìn)一步提高蜂窩狀多孔β-TCP材料孔壁的孔隙率,本研究通過(guò)添加馬鈴薯淀粉作為造孔劑對(duì)孔壁進(jìn)行了造孔。實(shí)驗(yàn)結(jié)果表明:當(dāng)造孔劑在生坯中分布較均勻時(shí),在蜂窩狀多孔材料孔壁中所形成孔隙的孔徑分布也較均勻;當(dāng)馬鈴薯淀粉添加量為30%時(shí),材料的總孔隙率提高到85 %,此時(shí)抗壓強(qiáng)度降低到約4.5 MPa,仍可基本滿(mǎn)足作為組織工程支架或非負(fù)重部位骨缺損修復(fù)材料的要求。為提高蜂窩狀多孔β-TCP材料的力學(xué)性能,本實(shí)驗(yàn)通過(guò)改變?cè)系幕瘜W(xué)計(jì)量數(shù)之比,同步合成了不同焦磷酸鈣(CPP)含量的CPP/β-TCP混合粉,研究了引入CPP對(duì)多孔β-TCP陶瓷的結(jié)構(gòu)和性能的影響。實(shí)驗(yàn)表明,CPP的引入通過(guò)在高溫下與β-TCP形成共融物促進(jìn)燒結(jié),并穩(wěn)定β-TCP晶相,從而可以提高β-TCP的燒結(jié)溫度,獲得更高材料燒結(jié)致密度,使多孔β-TCP陶瓷的抗壓強(qiáng)度得到提高。在造孔劑添加量為30 %的情況下,當(dāng)CPP含量為5 %,采用在1200℃保溫1 h的燒成制度,CPP/β-TCP多孔生物陶瓷的抗壓強(qiáng)度提高到約6.5 MPa。 本論文對(duì)比研究了幾種多孔磷酸鈣陶瓷材料的降解性能。研究表明,未加造孔劑制備的β-TCP多孔材料在PBS溶液中浸泡的過(guò)程是溶解與重結(jié)晶共同發(fā)生的過(guò)程,在材料表面析出針狀晶體,但加入了造孔劑制備的β-TCP和5%CPP/β-TCP多孔材料在PBS溶液中沒(méi)有發(fā)生明顯的析晶。添加30 %造孔劑進(jìn)行孔壁造孔的多孔材料在PBS溶液中隨著浸泡時(shí)間的延長(zhǎng)失重率有所增大,其中多孔5%CPP/β-TCP陶瓷的降解速率高于多孔β-TCP陶瓷。 另外,對(duì)于“適于骨組織長(zhǎng)入的孔徑”這一問(wèn)題,學(xué)者們所持觀點(diǎn)不一。本研究采用灌漿法調(diào)節(jié)蜂窩狀多孔材料的孔道尺寸、孔形狀,可以根據(jù)需要減小孔徑,通過(guò)灌注使孔道的直角變成圓弧角,有利于細(xì)胞的爬移。而且通過(guò)灌漿,提高了多孔磷酸鈣材料的力學(xué)性能。 細(xì)胞實(shí)驗(yàn)表明,所制備的多孔磷酸鈣材料具有良好的生物相容性,細(xì)胞在材料表面鋪展良好,且細(xì)胞在材料中可維持較好的增殖能力。
[Abstract]:In this paper, for the defects of the present preparation method and properties of the porous calcium phosphate bone repair material, the honeycomb-shaped porous calcium phosphate-TCP bone repair material was prepared by using the self-synthetic calcium-phosphate tricalcium (HCO3-TCP) powder for the first time. the hole wall of the porous material prepared by extrusion is made through the addition of a pore-making agent to form a three-stage hole calcium phosphate ceramic bone repairing material with a macro hole (extrusion forming hole), a micro-hole (hole for removing the pore-forming agent particle) and a sub-micron hole (sintering hole), and the strength of the porous carbon-TCP ceramic is improved by synchronously introducing the calcium pyrophosphate in the TCP-TCP synthesis process, the size and the shape of the extruded macro hole are adjusted through the perfusion technology, the high porosity, the one-way communication is prepared, the aperture is controllable, the aperture is uniform, a multi-stage pore calcium phosphate bone repair material with higher compressive strength. firstly, a suitable extrusion molding die is designed, and a piston type hydraulic extrusion molding method is adopted to prepare a porous branch with the advantages of adjustable aperture, uniform aperture, high aperture ratio, good mechanical property, suitability for industrial production and the like. The formation of TCP, CPP and CP-TCP powders by wet-milling is used to study the formation of TCP and CPP/ CP-TCP powders. The experimental results show that the synthesized TCP-TCP and CPP/ CP-TCP powders are suitable for extrusion. The method comprises the following steps of: mixing the powder and the additives according to a certain sequence to obtain the mud with good plasticity The optimum proportion of each additive is methyl cellulose M450 8%, liquid paraffin 10% and deionized water 32. The factors that affect the structure and properties of the extruded porous material, including the extrusion pressure, the drying system, the firing system, the mould structure and so on, are analyzed, and the reasonable process parameters are determined by the experiment. and the prepared honeycomb-shaped porous polystyrene-TCP bone repairing material has the ideal structure and the property, The extrusion-molded porous material, the extrusion orifice is square, the aperture is substantially uniform, about 850. m u.m, the porosity is about 74%, the compressive strength is about 17MP, a. In order to further improve the porosity of the cellular porous carbon-TCP material hole wall, the present study was conducted by adding potato starch as a pore-making agent to the hole wall. The experimental results show that when the pore-forming agent is distributed more uniformly in the green body, the pore size distribution of the pore formed in the hole wall of the cellular porous material is also uniform; when the amount of the potato starch is 30%, the total porosity of the material is increased to 85%, and the compressive strength is reduced to about 4.5. MPa, and can still be basically satisfied as a tissue engineering scaffold or a non-weight-bearing part bone defect repairing material In order to improve the mechanical properties of the cellular porous TCP/ TCP material, the CPP/ I-TCP mixed powder with different content of calcium pyrophosphate (CPP) was synthesized by changing the ratio of the stoichiometric ratio of the raw materials, and the structure and properties of the introduced CPP to the porous PTFE-TCP ceramics were studied. The experiment shows that the introduction of CPP promotes the sintering by the formation of a blend with the C-TCP at high temperature, and stabilizes the sintered-TCP phase, so that the sintering temperature of the P-TCP can be improved, the density of the higher material sintering can be obtained, and the compressive strength of the porous sintered-TCP ceramic can be obtained. When the addition amount of the pore-making agent is 30%, when the content of the CPP is 5%, the compression strength of the CPP/ L-TCP porous bioceramics is increased to about 6.5 when the content of the CPP is 5%, the firing system with the temperature of 1200 DEG C for 1h is adopted, and the compressive strength of the CPP/ L-TCP porous bioceramics is improved to about 6.5. In this paper, several kinds of porous calcium phosphate ceramic materials are studied in this paper. The results of the study show that the process of soaking the porous-TCP porous material in the solution of PBS is the process of co-occurrence of the dissolution and recrystallization in the solution of PBS, and the surface of the material The needle-like crystals were out, but the P-TCP and 5% CPP/ I-TCP porous materials prepared with the pore-making agent did not occur in the PBS solution and the degradation rate of the porous 5% CPP/ L-TCP ceramic is higher than that of the porous material-TCP ceramics. In addition, for 鈥減ore size suitable for bone tissue growth鈥，

本文編號(hào)：2386548