Structural features and mechanical properties of in situ-bonded meshes of segmented polyurethane electrospun from mixed solvents
Structural features and mechanical properties of in situ-bonded meshes of segmented polyurethane electrospun from mixed solvents
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DOI：
10.1002/jbm.b.30336
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发表时间：
2006-01-01
影响因子：
3.4
通讯作者：
Matsuda, T
中科院分区：
文献类型：
--
作者：
Kidoaki, S;Kwon, K;Matsuda, T
采用四氢呋喃(THF)和N，N-二甲基丙烯酰胺(DMF)的混合溶剂体系，研究了电纺嵌段聚氨酯(SPU)丝网的结构特征和力学性能与电纺参数(如聚合物浓度和溶剂混合比)和操作参数(如外加电压、气隙和流速)之间的关系。在建立了单一四氢呋喃溶液中固定四氢呋喃浓度下电纺SPU的结构与操作参数之间的关系后，以不同比例的四氢呋喃和DMF的混合溶剂[DMF含量分别为5%、10%和30%(v/v)]为原料，电纺SPU。扫描电子显微镜显示，随着DMF比例的增加，SPU纤维在接触部位的结合程度明显增强，形成的纤维直径减小。介孔测试结果表明：(1)随着DMF比例的增加，电纺SPU丝网的孔隙率降低。(2)孔径分布呈现3个具有代表性的不同孔径的峰(即约5、20和70微米)。(3)随着DMF比例的增加，20微米孔洞的比例明显减少。拉伸试验表明，随着DMF比例的增加，网孔的弹性增加。这种使用低沸点和高沸点溶剂的混合溶剂体系对电纺SPU网的结构特征和力学性能的调节可能在SPU纤维基基质或支架的工程中有用。
The relationships between the structural features and mechanical properties of electrospun segmented polyurethane (SPU) meshes and electrospinning parameters such as formulation (e.g., polymer concentration and solvent mixing ratio) and operation parameters (e.g., applied voltage, air gap, and flow rate) were studied with the use of a mixed-solvent system of tetrahydrofuran (THF) and N,N-dimethylacrylamide (DMF). After the relationships between the structure of electrospun SPU and the operation parameters under a fixed SPU concentration of single THF solution were established, SPU was electrospun from the mixed solvent of THF and DMF with different mixing ratios [DMF content: 5, 10, and 30% (v/v)]. Scanning electron microscopy showed that an increase in DMF ratio significantly enhances the degree of bonding between SPU fibers at contact sites and decreases the diameter of fibers formed. The porosimetric characterization showed the following: (1) The porosity of the electrospun SPU meshes decreased with an increase of DMF ratio. (2) The pore size distribution exhibited three representative peaks of different void sizes (i.e., approximately 5, 20, and 70 mu m). (3) The proportion of the 20-mu m void markedly decreased with an increase in DMF ratio. A tensile test on the meshes showed that an increase in DMF ratio induces an increase in elasticity of the mesh. Such a regulation of the structural features and mechanical properties of electrospun SPU meshes using a mixed-solvent system with low- and high-boiling-point solvents may be useful in the engineering of SPU-fiber based matrices or scaffolds.