仿生型壳聚糖-明胶/溶胶凝胶生物玻璃复合支架的制备及其矿化性能研究

利用冷冻干燥法制备出用于骨和软骨组织工程的壳聚糖-明胶/溶胶凝胶生物玻璃(CS-Gel/SGBG)仿生型复合多孔支架,并进行了孔隙率的测定和显微形貌的观察;探讨了各组分不同用量对CS-Gel/SGBG复合支架显微结构的影响以及复合支架在模拟生理体液中的仿生矿化性能。研究表明,通过调节各组分的不同用量,可以制备出三维连通的复合多孔支架,且孔隙率达到90%以上;在模拟生理体液中浸泡后发现CS-Gel/SGBG支架表面有大量结晶态类骨碳酸羟基磷灰石生成,表明复合支架有良好的生物矿化性能。     

壳聚糖/生物活性玻璃多孔复合支架的制备及界面增强作用

采用卵磷脂作为表面活性剂对溶胶-凝胶生物玻璃进行表面改性,并采用冷冻干燥法制备用于骨和软骨组织工程的壳聚糖/生物活性玻璃复合多孔支架(chitosan/bioglass porous composite scaffolds,CS/BGS),观察CS/BGS的显微形貌并测定抗压强度,探讨生物玻璃的表面改性对CS/BGS显微结构及力学强度的影响。研究表明:采用冷冻干燥法可以制备具有一定强度的三维连通的CS/BGS,且孔隙率达到90%以上。通过对生物玻璃表面改性可以在一定程度上提高CS/BGS的抗压强度。     

生物活性玻璃多孔材料的制备及性能研究

采用溶胶-凝胶法制备生物活性玻璃58S及77S;通过熔融法制备生物活性玻璃45S5,分别向上述3种生物活性玻璃粉体以及它们的混合物中添加一定比例的造孔剂,通过一定的烧结工艺制成具有不同组成的生物活性多孔材料,利用体外实验方法结合DTA,SEM及FTIR等材料显微结构及性能研究手段分析比较了各种多孔材料的显微结构、表面形貌、抗折强度及生物活性.研究表明:58S和45S5混合制备的多孔材料是一种具有良好生物活性和生物矿化特性的生物材料,可用于制备骨缺损填充材料和骨组织工程支架.     

溶胶-凝胶生物活性玻璃多孔支架的制备与性能的研究

通过溶胶—凝胶法合成制备了CaO-P2O5-SiO2系统溶胶—凝胶生物活性玻璃,并通过一定的造孔工艺将其制备成用作骨组织工程支架的多孔材料。采用体外模拟实验方法及DTA、SEM及FTIR等材料显微结构及性能研究手段分析研究了造孔剂种类、添加量对多孔材料的显微结构、表面形貌、抗折强度以及生物活性的影响。     

壳聚糖支架材料的制备、表面修饰及细胞粘附性能的研究

通过冷冻干燥法进行壳聚糖(Chitosan)多孔支架材料的制备,使用I型明胶对所制得的支架材料进行表面修饰,用于生物医用可降解复合材料的仿生构建.对所制备的支架材料分别进行密度、孔隙率和降解率等物理性质测定,并使用新西兰兔来源的骨髓间充质干细胞(Bone marrow mesenchymal stem cells, BMSCs)检验支架材料的细胞粘附和生物相容性能.以未经表面处理的该种材料作为对照组,对MSCs-Chitosan复合物分别进行扫描电镜和Hoechst染色等,检测MSCs(间充质干细胞)在支架材料表面的生长、粘附和分布形态.结果显示两种壳聚糖浓度制备的多孔支架材料的空隙率分别为(86.85±2.42)%和(71.50±3.29)%,孔径为90~130 μm,MSCs在经明胶表面修饰的材料表面表现出良好的粘附、伸展性能.此外,本研究还对1-乙基-(3-二甲基氨基丙基)碳酰二亚胺(1-ethyl- (3-dimethylanimopropyl) carbodiimide, EDC)交联剂对壳聚糖基支架性能的影响进行了初步研究.研究表明,通过明胶修饰构建的仿生明胶/壳聚糖人工基质材料,具有良好的生物相容性能,作为一种理想的组织工程用支架材料,适于细胞在其上的粘附与增殖.     

聚乙二醇为分散剂制备纳米生物活性玻璃粉体

采用溶胶-凝胶共沉淀方法结合冷冻干燥技术制备颗粒尺寸在纳米级的生物活性玻璃(NBG),研究了加入分散剂聚乙二醇(PEG-10000)对玻璃颗粒的分散性能、微观形貌和生物活性的影响.结果表明:没有加入PEG制得的纳米生物活性玻璃颗粒呈现不规则形态,粒径小于50 nm.加有PEG的玻璃颗粒形状趋于规则的球形,分散性大大提高,颗粒粒径在40～100 nm,而且加入PEG的浓度越高,制备的颗粒粒径越小.通过比较纳米级的生物活性玻璃与溶胶-凝胶生物活性玻璃在模拟人体体液(SBF)中的表面矿化研究,发现纳米生物活性玻璃比溶胶-凝胶生物活性玻璃有更高的生物活性.     

溶胶-凝胶生物活性玻璃的纳米结构分析研究

利用溶胶-凝胶低温合成法制备了CaO-P2O5-SiO2系统生物活性玻璃骨修复及骨组织工程材料.利用SEM、BET及XRD等方法对溶胶-凝胶生物活性玻璃的微观结构及其组成对材料微观结构的影响进行了分析,并同目前已临床应用的45S5生物活性玻璃进行了比较.研究发现由溶胶-凝胶法制备的生物活性玻璃是由纳米级微球构成,其高比表面积是由其纳米微球之间的孔隙所致.这种高比表面积对于提高材料的表面吸附能力及生物矿化功能具有重要作用.根据等大球体最紧密堆积原理建立了溶胶-凝胶生物活性玻璃纳米孔隙尺寸近似计算模型,并对其孔隙结构进行了分析计算.     

APTES改性生物活性玻璃的工艺研究

为了改善溶胶-凝胶生物活性玻璃(BG)与高分子材料的界面相容性,采用氨丙基三乙氧基硅烷(APTES)偶联剂改性溶胶凝胶生物活性玻璃.用傅立叶红外吸收光谱(FTIR)考察在不同的反应浓度,反应时间和反应溶剂的条件下对BG接枝改性APTES的接枝率的影响.研究表明,以正己烷为溶剂、在80 ℃、氮气保护条件下,反应12 h,接枝率最大.     

TiO_2/壳聚糖/明胶复合棉织物的制备及功能特性

采用了溶胶-凝胶法制备了TiO_2溶胶,使纳米TiO_2在棉织物的表面和内部原位生成,从而实现无机纳米TiO_2粒子与棉织物的牢固结合;再与壳聚糖明胶混合液进行浸轧,制备TiO_2/壳聚糖/明胶复合棉织物材料。用扫描电镜和X射线衍射仪对样品的形貌和结构进行表征,并测试了样品的力学性能、耐洗牢度和光催化性能。结果表明:原位生成的TiO_2与棉织物结合牢固,粒径均匀,分散性较好;纳米TiO_2主要是锐钛矿晶型;所制得试样对活性红染液具有良好的光催化降解作用。     

CaO-P2O5-SiO2系统溶胶-凝胶生物活性多孔材料的降解特性及生物活性研究

通过溶胶—凝胶法合成制备了CaO—-P2O5—SiO2系统溶胶—凝胶生物活性玻璃，并通过一定的烧结工艺将其制备成用作骨组织工程支架的多孔材料。采用生物材料的体外实验方法(in vitro)及DTA、XRD、SEM及FTIR等材料显微结构及性能研究手段分析研究了烧结温度对多孔材料的显微结构、生物活性和可降解性能的影响。     

PP-g-MAH增容PP/BN/Al2O3导热绝缘复合材料

以(3-氨丙基)三乙氧基硅烷(KH550)处理氮化硼/氧化铝(BN/Al2O3)导热粉体,在导热粉体表面引入氨基;通过熔融共混制备聚丙烯接枝马来酸酐(PP-g-MAH)增容的聚丙烯(PP)/BN/Al2O3导热绝缘复合材料。研究PP-g-MAH和导热填料的用量以及加工条件(转速、温度)对复合材料性能的影响。结果表明,在主机转速为300 r/min、PP-g-MAH为4g、导热填料的用量为50%时,复合材料的导热系数达到了0.7 W/(m·K),拉伸强度为17.65 MPa;添加相容剂后,复合材料和导热填料之间的相容性得到改善。     

Effect of silane treated fly ash on physico-mechanical,morphological, and thermal properties of recycled poly(vinyl chloride) composites

The silane treatment on properties of fly ash (FA) and development of its composite using recycled poly(vinyl chloride) (r-PVC) material retrieve from waste wires and cable insulation are investigated in this work. The use of (3-aminopropyl)triethoxysilane was employed as a coupling agent with some other essential additives. The composites sheet was prepared by means of the melt mixing process and go along with the compression molding process. The superior properties on compatibility between silane-modified FA (FA(Si)) and r-PVC were successfully studied using rheological, thermomechanical, morphological, and water absorption analysis. Primary analysis of r-PVC and FA was employed using Fourier transform infrared spectroscopy analysis. The thermal stability of composites was stable up to 187°C. In addition, significant enhancement on tensile strength as well as young's modulus of composite as compared to untreated r-PVC/FA composites. Morphological properties of silane treated FA based composites presented the good distribution and excellent uniformity with higher wettability of FA particles within r-PVC matrix. The water absorption test showed decrease in water absorption with increase silane treatment concentration FA in the r-PVC matrix. It was remarkable to note that silane treated FA can be prepared as a composite using r-PVC matrix with further modified properties.     

Preparation and characteristics of polypropylene-graft-maleic anhydride anchored micro-fibriled cellulose: its composites with polypropylene

The surface modification of micro-fibriled cellulose (MFC) was carried out through the hydrolysis–condensation reaction using (3-aminopropyl)triethoxysilane (APS) and then was subsequently treated with polypropylene-graft-maleic anhydride (MAPP) to give desired MAPP-anchored MFC (MAPP-a-MFC). The confirmation of surface modification for the pristine MFCs was characterized by FTIR, EDX, and XPS measurements. The polypropylene (PP) composites with MAPP-a-MFC were prepared via typical melt-mixing method. The effects of MAPP-a-MFC on the physical properties of the PP composites were investigated. From the results of mechanical properties, thermal behaviors, and the morphology of the composites, it was found that there was an improved interfacial adhesion between the MAPP-a-MFC and PP matrix in the composites.     

Improvement of mechanical,thermal and tribological properties of (3-aminopropyl) triethoxysilane-modified graphene/polyimide nanocomposites by in situ polymerisation

To elucidate the improvement and the principle of graphene modification on the polyimide (PI), (3-aminopropyl) triethoxysilane-modified graphene (PMG), was designed and prepared by anchoring the (3-aminopropyl) triethoxysilane (APTS) chain on the graphene sheet surface, and used to synthesise PI composites by in situ polymerisation. The unique surface modification significantly improved the compatibility and dispersion of graphene in the PI matrix. Tensile strength and Young’s modulus of 1.0PMG/PI was 109.45?MPa and 1.73?GPa, which increased by 54.26 and 86.02% from neat PI, respectively. The tribological properties and mechanism were also discussed. The friction coefficient and wear rate of 1.0PMG/PI (0.287, 2.291×10^?5mm³?Nm^?1) decreased by 47.53% and 35.06%, respectively. This improvement of the tribological properties was mainly caused by the cooperative interaction of the improved mechanical and thermal properties of the composites and the high self-lubricity of modified graphene.     

驱蚊蚊帐的制备和表征

采用氨基丙基三乙氧基硅烷偶联剂处理涤纶蚊帐,然后将处理后的蚊帐浸泡在添加溴氰菊酯悬浮液的聚氨酯胶粘剂乳液中,室温固化得到表面含有溴氰菊酯的蚊帐,该蚊帐具有驱蚊效果。利用紫外可见吸收光谱可以非常简便地测定蚊帐中溴氰菊酯含量。     

介孔生物玻璃复合支架及其骨组织修复应用

介孔生物玻璃 (Mesoporous Bioglass, MBG) 支架由于高的比表面积和介孔结构而 具有优异的成骨活性、生物降解性以及局部药物递送功能。MBG 支架可提供细胞增殖/生长、 细胞外基质沉积、营养物质获取的场所,引导新骨生长而修复骨缺损。然而,纯 MBG 支架的 力学强度低、脆性大而使其应用于骨缺损修复受到限制。将 MBG 结合生物高分子或其他生物 陶瓷制备 MBG 复合支架成为解决上述问题的有效策略之一。本文将基于 MBG 复合支架的骨组 织修复应用背景,简单介绍 MBG 复合支架的制备方法,系统总结 MBG 复合支架在骨组织修复 领域中的应用,最后对 MBG 复合支架的发展前景与挑战进行展望。     

Mesoporous Silica Nanoparticles (MCM-41) Coated PEGylated Chitosan as a pH-Responsive Nanocarrier for Triggered Release of Erythromycin

A pH-responsive drug delivery system based on core shell structure of mesoporous silica nanoparticle (MSN) and chitosan-PEG copolymer was prepared and characterized by Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), scanning electron microscope (SEM), and high-resolution transmission microscope (HR-TEM) techniques. In order to improve compatibility MSN and drug, mesoporous nanosilica was modified by 3-aminopropyl triethoxysilane. The release of erythromycin (a macrolide antibiotic) as a model drug was investigated in two pHs, 7.4 and 5.5.     

磺酸型水性聚氨酯／改性SiO2复合材料的制备与性能研究

用硅烷偶联剂3-氨丙基三乙氧基硅烷（KH-550）对纳米二氧化硅（SiO2）进行改性,采用原位聚合将改性后的SiO2引入到磺酸型水性聚氨酯（WPU）中。结果表明,硅烷偶联剂与SiO2表面羟基发生了化学反应;随着改性SiO2含量的增加,复合材料的粒径逐渐增大,且复合材料的耐水性则得到明显改善;拉伸强度则随改性SiO2含量的增加先增大后减小,断裂伸长率逐渐减小;当改性SiO2质量分数为2．0％时,复合材料的拉伸强度最大,其值为39．62MPa,粒径为77．16nm,吸水率为13．69％,复合材料的综合性能较好。