丝素蛋白/羟基磷灰石复合多孔材料的制备及其孔结构

用喷雾干燥法和冷冻干燥一球磨法，分别制得丝素蛋白（SF）粉末和羟基磷灰石（HA）粉末。经X-射线衍射、红外光谱测试，表明SF粉末以无定型结构为主，HA粉末的结晶度较低。用模压成型法，将SF、HA粉末复合，以NaCl为致孔剂，制成平均孔径为157-220μm的SF／HA复合多孔材料。测试和分析结果说明，随着制备时NaCl添加量的增大，所制得的多孔材料的孔隙率及孔密度增大；随着材料内SF含量的增大，多孔材料的孔隙率减小、孔密度增大。     

沥滤/发泡组合法制备多孔材料及性能研究

为研究粒子/发泡组合法制备多孔材料的性能,以NaCl为沥滤剂,NH4HCO3为发泡剂,利用组合法制备了聚乳酸/β-磷酸三钙多孔复合材料.通过扫描电子显微镜(SEM)观察表面形貌与内部孔结构,重量法测定孔率与相对密度,以及MicroTester 材料试验机检测多孔材料的力学性能.结果表明:NaCl粒子沥滤/NH4HCO3化学发泡组合法具有一定的协同效应:与单一的NaCl沥滤法相比,组合法制备材料的致孔剂残留率低;与单一的NH4HCO3发泡法相比,组合法制备材料的孔结构连通性得到有效提高;同时,力学性能有也一定的提高.     

氯化钠作为造孔剂制备含氯多孔羟基磷灰石实验研究

采用化学沉淀法,制备纳米HA粉体．采用造孔剂法,首次利用NaCl作造孔剂,将纳米HA粉体和NaCl颗粒按一定比例混合压制成型,经高温烧结制备出多孔含NaCl的HA材料．利用XRD、SEM、EDX手段研究多孔HA的组成成分、微观形貌、孔径尺寸及孔隙率．研究结果表明：NaCl是比较理想的造孔剂材料,可制备孔隙率、孔径尺寸、形貌可控的多孔材料．造孔剂含量为30％,尺寸在160～200目时,造孔效果最好;在烧结温度1200℃烧结时,NaCl会与HA发生反应,生成Ca5（PO4）3Cl,Ca9．54P5．98O23．58Cl1．6（OH）2．74等新的物相．     

聚氨酯/乙炔黑多孔复合材料的结构及吸附性能研究

为了研究改性剂含量以及干燥方式对聚氨酯多孔材料吸附性能的影响，采用热致相分离法制备聚氨酯/乙炔黑多孔复合吸附材料，系统研究了不同乙炔黑浓度以及常温真空干燥对材料结构性能的影响，并优化得到了最佳合成条件。研究结果表明：当乙炔黑加入量的质量分数为2%～3%时，多孔整体材料呈现更加均匀的三维贯穿分级微米孔结构，吸附速率最高达1.5×10^-3g/s，是纯聚氨酯热塑性(TPU)多孔材料的8倍。采用常温真空干燥制备得到的聚氨酯多孔吸附材料对植物油具有良好的吸附能力，对植物油的循环吸附量均大于90%，与传统的冷冻干燥相比具有制备简单、成本低廉等优势。     

聚酯型聚氨酯多孔膜的制备和表征

以异氰酸酯(MDI)、聚己二酸丁二酯(PBA)、1,4-丁二醇(BDO)和聚乙二醇(PEG)为原料合成了聚酯型聚氨酯(PU),并优化了聚合工艺;考察了聚氨酯浆料浓度、凝固浴的温度和浓度以及致孔剂等因素对聚氨酯多孔膜结构和性能的影响.结果表明,以MDI为硬段物质、PBA为软段物质、BDO为扩链剂合成的聚氨酯具有良好的成膜性能.聚氨酯膜的结构及性能最优的成膜条件为:聚氨酯浆料浓度为30%～40%,凝固浴温度为30℃,凝固浴浓度要低于10%,同时添加适量的PEG或BDO等致孔剂.     

PVDF/PEG锂盐导电聚合物多孔膜的制备及导电性能研究

以不同组成比的PVDF/PEG复合制成微多孔状材料,然后利用该材料与锂盐制备复合电解质薄膜,并对所得薄膜样品进行偏光显微镜(POM)、X射线衍射(XRD)及扫描电子显微镜(SEM)分析和表征.通过对比微多孔状材料表面的PVDF/PEG复合电解质膜与未加致孔剂的PVDF/PEG薄膜的导电性能,研究表面微观结构对离子导电行为的影响.结果表明,PVDF/PEG复合电解质薄膜对乙酸蒸气具有择优性响应性,在复合薄膜中引入微多孔结构,增大了比表面积,响应性能明显改善.     

多孔淀粉微球的制备及应用

对淀粉微球致孔方法及多孔淀粉微球的应用性能进行了研究,首先确定了微球制备的基本条件并且进行了优化。用于制备淀粉微球的最佳条件为:玉米淀粉质量分数为5%,交联剂用量0.28g/g,乳化剂用量为0.05g/mL,油水相体积比3∶1,机械搅拌速度600r/min,由这些因素组成了油包水反相乳液体系。在此基础上,对微球致孔方法进行了研究,分别使用冷冻干燥法和加入致孔剂法对微球致孔,得到了具有多孔结构的微球,通过扫描电子显微镜观察了成孔效果并且研究了不同PEG6000添加量对微球孔隙率的影响。以亚甲基蓝作为模拟药物,研究了多孔微球的药物负载性能,在PEG6000添加量为淀粉质量的30%时,多孔微球的孔隙率为89%,载药量为158mg/g。     

pBMP/Ce-TZP陶瓷复合人工骨材料的研究

研究H-Z涂层内以CeO2稳定的四方相氧化锆多孔陶瓷,与猪骨形态发生蛋白复合而成的人工骨。结果表明,人工骨材料的羟基磷灰石多孔层平均气孔率为34.95%,吸水率为8.63%,体积密度为3.84 g/cm3,断裂韧性(KIC)为10.95 MPa.m1/2,显微硬度(HV)为1 051。用XRD和SEM测定基体晶相为t-ZrO2,H-Z涂层中有t-ZrO2、m-ZrO2、d-TCP和少量的HA等晶相,其多孔结构有利于pBMP、骨组织长入和形成化学键性结合达到永久性生物学固定的目的。具有良好力学强度及增韧性。材料的生物相容性与诱导成骨能力良好,促进骨缺损的修复。     

聚丙烯MI及成核剂添加量对TIPS法多孔膜结构与透过性能的影响

研究了等规聚丙烯(iPP)/邻苯二甲酸二丁酯(DBP)/邻苯二甲酸二辛酯(DOP)/成核剂TM-1体系的热致相分离(TIPS)行为,采用熔融指数(MI)较低的聚丙烯T30S与MI较高的F401作对比研究.采用示差扫描量热仪(DSC)测定成核效应,采用光学显微镜观察iPP成核与晶粒生长.经过加热模压并控制冷却速率制备iPP多孔膜,对膜结构及其透过性能进行了表征.结果表明:相比于F401/DBP/DOP体系,TM-1对T30S/DBP/DOP体系表现出更强的成核效应;不同MI聚丙烯制备的多孔膜结构明显不同,加入成核剂后,T30S型iPP多孔膜结构由紧密融合、内含胞腔孔的球晶结构转变为晶粒组成胞腔壁、相对开放的胞腔孔结构,而F401型iPP多孔膜的结构仍为紧密融合、内含胞腔孔的球晶结构,只球晶尺寸变小;相同成核剂添加量下,用T30S制备的多孔膜透过性能更好.     

热致相分离/粒子滤出法制备多孔支架的研究

分别采用了简单相分离法和热致相分离/粒子滤出法制备了聚乳酸多孔支架材料。在简单相分离法中,改变聚乳酸(PLLA)分子量,PLLA/1,4-二氧六环比例以及粗化时间等条件,分析其对支架材料孔隙率、强度和孔连通性的影响。在复合法中,采用石蜡微球作为致孔剂制备聚合物多孔支架,并通过改变石蜡微球的尺寸,疏密程度等条件来控制多孔支架的孔隙率、强度以及孔连通性。结果表明:采用后者制备的多孔支架材料,孔的大小均一、孔隙率高、连通性好。     

Enhanced Interfacial Adhesion in HDPE/HA Composites by Surface Modification of HA Particles via in situ Polymerization and Copolymerization

1Introduction Particulatehydroxyapatite(HA)reinforcedhigh densitypolyethylene(HDPE)compositehasbeendevel opedsinceearly1980sasananaloguematerialforbone replacement[14].Thecombinationofbioactive,stiff,butbrittleHA,andlowelasticmodulus,ductileHDPEal lowsthecompositehavingagoodbiocompatibilityandad equatemechanicalproperties.Unliketheconventionalim plantmaterialssuchasmetalsandceramics,HDPE HAcompositesmatchthemechanicalproperties(ie,stiffnessandstrength)ofcorticalbone.Thereby,itavoidsthe…     

Preparation and Mechanical Properties of HIPS Composites Containing PS-grafted-hydroxyapatite Particles

1Introduction Hydroxyapatiteisawell knownbioceramicthathas gainedmuchattentionfrombiologistsandbiomaterial scientists[1].Duetoitsreasonablemechanicalbehavior underlow loadconditionsandexcellentbiocompatibility,combinedwithslowreplacementbythehostboneafter…     

Preparation and characterization of nano-hydroxyapatite/polyvinyl alcohol gel composites

Nano-hydroxyapatite reinforced poly(vinyl alcohol) gel (nano-HA/PVA gel) composites has been proposed as a promising biomaterial, especially used as an articular cartilage repair biomaterial. In this paper, nano-HA/PVA gel composite was prepared by in situ synthesis method and incorporation with freeze-thaw cycle process. The microstructure and morphology were investigated by X-ray diffraction, TEM, SEM and FTIR. The results showed that the size of HA particles synthesized in PVA solution was on the nanometer scale. Both the size and crystallinity of HA particles synthesized in PVA solution decreased compared with that of HA synthesized in distilled water. The nano-HA particles were distributed in PVA matrix uniformly due to the effect of PVA solution as a dispersant while low content of HA particles in the composites. On the contrary, with high content of nano-HA particles in the composites, the particles tended to aggregate. The result of FT-IR analysis indicated that the chemical bond between nano-HA particles and PVA matrix existed. The conformation and degree of tacticity of PVA molecule changed because of the addition of HA particles. Furthermore, the interfacial strength of the composites was improved due to the interaction between nano-HA particle and PVA matrix and this was beneficial to improving the mechanical properties of the composites.     

纳米羟基磷灰石复合陶瓷生物摩擦学行为研究

采用沉淀法合成了纳米羟基磷灰石（HA）粉体，无压烧结工艺制备了HA／PSZ陶瓷复合材料．利用材料试验分析系统（MTS）和纳米硬度分析测试系统（Triboindenter）测定了复合材料的宏观和微观力学性能，用销盘式摩擦磨损试验机考察了血浆润滑条件下复合材料的生物摩擦学性能，探讨了力学性能与摩擦学性能之间的关系．结果表明，无压烧结HA／PSZ复合陶瓷材料断裂韧性比纯HA陶瓷提高近2．7倍，弯曲强度提高近1倍．纳米硬度最高值为10．6GPa，纳米弹性模量为156．OGPa．血浆润滑条件下，HA／PSZ陶瓷和UHMWPE摩擦副的摩擦系数与HA的含量有关，UHMWPE的磨损率与HA／psz复合陶瓷摩擦副的硬度和断裂韧性存在反比关系．     

Tribological Properties of Polyvinyl Mcohol Hydrogel Reinforced with Nanometer Hydroxy Apatite

As a potential artificial cartilage material,the friction and wear properties of nano-hydroxy apatite(HA)particles filled poly(vinyl alcohol)hydrogel(PVA-H)composites sliding against stainless steel disk under water lubrication condition were studied by using a four ball tester.The worn surfaces were investigated by using a scanning electron microscope(SEM)to determine the wear mechanisms.Experimental results show that filling HA to PVA-H will slightly increase the friction coefficient of composites with the increasing of HA content under water lubrication condition.Meanwhile,HA particles can greatly reduce the wear mass loss of the PVA-H composites and enhance the load carrying capacity,the wear loss of the 1 wt% HA reinforced PVA-H composites can be decreased by 30 percent under 2.0 MPa to 50 percent under 0.5 MPa contact pressure.We also found that 2 wt% HA content of composites increase the wear mass loss under the same condition.SEM examination shows that the worn surface of low HA containing(1 wt%)composites are much smoother than that of pure PVA-H or high HA containing(2 wt%)composites under 1.5 MPa contact pressure.It is also found that there are big hole and big reunited HA particles in the surface of 2 wt% HA containing composites,which leads to deterioration of the surface of samples under higher loads in water lubrication.These results may be useful in the tribological design of artificial articular cartilage material.     

Tribological Properties of Polyvinyl Alcohol Hydrogel Reinforced with Nanometer Hydroxy Apatite

As a potential artificial cartilage material, the friction and wear properties of nano-hydroxy apatite （HA） particles filled poly （vinyl alcohol） hydrogel （PVA-H） composites sliding against stainless steel disk under water lubrication condition were studied by using a four ball tester. The worn surfaces were investigated by using a scanning electron microscope （SEM） to determine the wear mechanisms. Experimental results show that filling HA to PVA-H will slightly increase the friction coefficient of composites with the increasing of HA content under water lubrication condition. Meanwhile, HA particles can greatly reduce the wear mass loss of the PVA-H composites and enhance the load carrying capacity, the wear loss of the 1 wt% HA reinforced PVA-H composites can be decreased by 30 percent under 2.0 MPa to 50 percent under 0.5 MPa contact pressure. We also found that 2 wt% HA content of composites increase the wear mass loss under the same condition. SEM examination shows that the worn surface of low HA containing （1 wt%） composites are much smoother than that of pure PVA-H or high HA containing （2 wt%） composites under 1.5 MPa contact pressure. It is also found that there are big hole and big reunited HA particles in the surface of 2 wt% HA containing composites, which leads to deterioration of the surface of samples under higher loads in water lubrication. These results may be useful in the tribological design of artificial articular cartilage material.     

食用级吸附淀粉微球的制备

采用反相悬浮交联的方法,以可溶性淀粉为原料,同时以三偏磷酸钠作为交联剂,Span80作为乳化剂,聚乙二醇6000作为致孔剂,大豆油为油相制备食用级吸附淀粉微球,研究了pH、反应温度、交联剂用量、反应时间和致孔剂用量等对淀粉微球制备的影响。在pH为10、反应温度50℃、交联剂用量0.8%、反应时间5h、致孔剂用量0.08g/g淀粉条件下,得到的多孔性淀粉颗粒的吸附性能最好,对亚甲基蓝吸附量为1.761mg/g淀粉颗粒。通过扫描电镜、N2吸附-脱附对产物结构进行表征,证明淀粉微球具有多孔结构,比表面积为1 699m2/g。     

Induced bone by calcium ohosphate (Ca-P) ceramics after 2-years implantation

The changes of induced bone with four kinds of Ca-P ceramics after 2 years implantation in the dorsal muscles of rabbits were investigated. After 2 years implantation, mature bone (with a lamellar structure after the remodeling process) with bone marrow was observed in HA1100 (HA, micro+macro porous), HA900 (HA, micro+macro porous) and BCP (HA/TCP=7:3, micro+ macro porous), and no bone formation was observed in HA1200 (HA, macro porous) ceramics. The induced bone neither disappeared nor grew uncontrollably, and was seen inside the pores of the implants or on the outer surface under the fibrous layer after 2 years. No bone formation was observed in the soft tissues distant from the implants. These results indicate that heterotopic bone formation induced by Ca-P materials did not give rise to uncontrolled growth over time, and the induced bone is limited to the inside or around the implants. Moreover, ectopic bone formation on the outer surface of the implants was detected in rabbits after 2 years.     

一步法制备羟基磷灰石/丝素蛋白复合材料的条件研究

提出了一种制备HA/SF复合粉末的新方法.以磷酸氢二钠、无水氯化钙和丝素蛋白为原料制备羟基磷灰石/丝素蛋白(HA/SF)复合粉末,通过X-射线衍射(XRD)、扫描电子显微镜(SEM)和红外吸收光谱(FIR)等检测手段,探讨了反应酸度、反应温度、反应时间,丝素蛋白加入量和原料加入顺序对制备HA/SF复合粉末的影响,确定了最佳的制备条件;该方法可降低溶解丝素蛋白的温度,达到节约能源的目的.