【作者】 樊晓娜；

【导师】 熊杰；

【作者基本信息】 浙江理工大学 ， 材料加工工程， 2012， 硕士

【摘要】 本文旨在改善静电纺玉米醇溶蛋白(zein)纳米纤维膜力学性能的不足，通过共混和同轴静电纺丝制备出力学性能较好的zein/PBS（聚丁二酸丁二醇酯）复合纳米纤维膜支架，通过生物学评价可以获得具有良好细胞相容性的zein/PBS组织工程支架，以扩大静电纺玉米醇溶蛋白在组织工程支架材料领域的应用。首先通过静电纺丝技术制备出zein和PBS不同共混比例的复合纳米纤维膜，并对不同比例下所得复合纤维的形貌、结构、热性能、力学性能及亲水性进行研究。结果表明，PBS的加入提高了zein的可纺性，随着PBS共混质量比的增加，纤维平均直径增加，纳米纤维膜的结晶性能逐渐变好，且整个纳米纤维膜的熔融热增加。力学性能测试表明，随着PBS含量从25%增加到75%，复合纳米纤维膜的最大拉伸强度和应变逐渐增加，力学性能得到显著改善。通过亲水性实验得出，zein/PBS共混纤维膜的亲水性得到明显提高。为改善聚丁二酸丁二醇酯（PBS）的性能以满足不同组织工程支架的要求，将多壁碳纳米管（MWNTs）作为增强填料混合到PBS溶液中制备电纺MWNTs/PBS复合纳米纤维膜。研究了不同含量的MWNTs对PBS纤维各项性能的影响。结果表明：MWNTs分散于PBS纤维中，MWNTs的添加使纤维平均直径减小，热稳定性随着随MWNTs含量的增加而提高，透射电镜和力学性能结果显示当PBS中MWNTs的含量为1.5%时，MWNTs在PBS基体中分散良好，此时MWNTs/PBS复合纳米纤维拉伸强度和应变达到最大值。通过同轴静电纺丝法成功制备出zein-PBS皮芯结构复合纳米纤维膜，探讨芯层PBS含量、皮层zein含量、皮层纺丝流率对复合纳米纤维膜形貌、结构和力学性能的影响。结果表明：当皮层zein含量固定时，芯层PBS浓度偏高或偏低均不利于同轴静电纺丝过程的稳定性，当芯层PBS为6%时，皮芯结构复合纳米纤维具有较高的力学强度。固定芯层PBS浓度，纤维直径随着皮层纺丝液浓度的增加而变大，所得皮芯结构静电纺膜的拉伸强度和断裂伸长率均增大。在皮芯层纺丝速率均为0.006ml/min时能够得到形貌均匀、皮芯结构完整的复合纳米纤维。当芯层加入少量MWNTs，复合纤维整体直径降低且纤维变得更加均匀，纤维膜的力学性能和热性能均有提高。最后，通过体外小鼠成纤细胞(L929)培养，对纳米纤维支架进行生物性能评价。结果表明，细胞能够很好地在静电纺zein、zein/PBS、皮（zein）-芯（PBS）、皮（zein）-芯（PBS/MWNTs）结构复合纳米纤维支架上生长繁殖，其对细胞无毒害作用，具有良好的生物相容性。芯层MWNTs的加入不会对细胞生长繁殖造成不利影响。同轴静电纺丝制备的结构复合纳米纤维支架有明显优势，其OD值高于共混zein/PBS的OD值，体现了皮芯结构在细胞相容性方面的优势，结合力学性能可知，两种支架材料作为组织工程支架均具有很好的应用前景。更多还原

【Abstract】 In this thesis, the zein/Poly(butylene succinate)(PBS) composite nanofibrous membranescaffold with improved tensile strength were fabricated by the blend and coaxial electrospinning inorder to synchronously enhance the mechanical property of zein, and also obtain zein/PBScomposite tissue engineering scaffolds, which possess a better cytocompatibility depending onbiological evaluation, and finally extend the application field of zein in biomaterials.Zein/PBS blends with different mass ratios were prepared to fabricate composite nanofibrousmembrane scaffold by electrospinning, and the morphology, structure, thermal performance,mechanical properties and hydrophilicity of composite fibers were studied. The results showed theelectrospun spinnability of zein was improved by PBS. The average diameter of zein/PBScomposite fibers increased and the crystallinity of composite nanofibrous membrane scaffoldincreased with the addition of PBS content. The mechanical properties were improved effectively.At the same time hydrophilicity of composite nanofibrous membrane scaffold was greatlyimproved.In order to improve the properties of PBS, Multi-walled carbon nanotubes (MWNTs) wasmixed with PBS solution to prepare electrospun MWNTs/PBS composite nanofibous scaffold fordifferent tissue engineering scaffolds. The performance of PBS fibers with different contentMWNTs was researched. The results showed that MWNTs have been dispersed in PBS fibers, thediameter of the fibers decrease due to the addition of MWNTs, with the increase of MWNTs thethermal stability was enhanced. When the content of MWNTs is1.5%, it disperses well in PBSmatrix and the composite nanofibous membrane scaffold have the best failure strength and failureelongation.Sheath(zein)-core(PBS) composite nanofibrous membrane scaffold were successfully preparedby coaxial electrospinning. The effects of core and sheath concentrations and flow rate of the outerzein fluid on its morphology, structure and mechanical properties were investigated. The resultsrevealed that fixed sheath concentration, however higher or lower one can resist co-electrospinningstability.When the core concentration was6%, the composite nanofiber membrane scaffold had better mechanical properties. The composite fiber diameter increased and mechanical properties ofsheath-core structured composite fibers became more higher with increasing of sheath concentrationunder unchanged core concentration. The composite nanofibers with uniform morphology andintegrated sheath-core structure were obtained when both of the core and sheath spinning rates were0.006ml/min. After adding MWNTs into the core solution, the morphology ultrafine fibrousmembranes was well and the fiber diameter decreased, and the failure strength and thermalproperties became increased.Finally, through in vitro cell culture experiment, the cyto-biological of the five compositenanofibrous membrane scaffolds was investigated. The results showed that the L929mousefibroblasts proliferated well on zein, PBS, zein/PBS, sheath（zein）-core（PBS） and sheath（zein）-core（PBS/MWNTs） composite nanofibrous membrane scaffolds.. The five scaffolds werenon-toxic, and the cytocompatibility were fabourable. MWNTs added to core did not influence cellgrowth and proliferation. The two sheath-core ultrafine composite fibrous scaffolds had morecytocompatibility than zein/PBS composite nanofibrous memberane scaffolds. Their OD values arehigher than that of zein/PBS composite nanofibrous scaffolds, and the mechanical properties werebetter., so they have great application potential in tissue engineering scaffolds.更多还原