從過去我們製備組織工程血管支架的經驗中，我們發現電紡纖維薄膜的機械性質取決於纖維的方向與纖維角度的分佈。為了能夠更深入了解纖維的方向與纖維角度的分佈對薄膜的機械性質的影響，在本研究中，我們分別使用了三種材料(PU, PCL, PLA)，並且探討三種不同纖維排列程度(Random、中度纖維順向性、高度纖維順向性)與兩種角度(30度與45度)分佈在三種材料之電紡薄膜的力學性質。為滿足上述需求，我們利用旋轉滾筒收集紡絲，製備內含不同順向性纖維之薄膜。並將內含中、高度順向性之薄膜在特定角度下相疊以製備具特定方向之薄膜。另一方面，就電紡絲技術進行複合材料而言，有兩種複合方式，分別為混合溶液電紡(blend electrospinning)與共同電紡(co-electrospinning)，在本研究中，我們將使用剛性較為接近的兩種材料(聚己內酯, 聚乳酸)以兩種不同複合方式複合，並探討其機械性質之差異。在力學測試的部份，我們利用雙軸測試薄膜力學性質。結果顯示，當纖維順向性越大，薄膜之兩軸所呈現的力學性質差異越大。內含兩股纖維與x軸夾角為45度薄膜之兩軸力學性質會相同，而內含兩股高度纖維順向性並且纖維與x軸夾角為45度薄膜其剛度會高於中度纖維順向性並且纖維與x軸夾角為45度薄膜。在複合材料的部分，兩種複合形式間有著很大的力學性質差異，在相同的成分比例下，混合溶液電紡薄膜的力學性質比共同電紡更接近聚乳酸。

Previous studies showed that the mechanical properties of electrospun membranes depend on fiber orientations and fiber alignment. In order to better understand the effect of the fiber orientations and fiber alignment on the mechanical properties of the membranes, we used three materials (PU, PCL, and PLA) to fabricate the electrospun membranes. On the other hand, there are two methods of making composite membranes by the electrospinning, namely blend electrospinning and co-electrospinning. In this study, we used two materials (PCL and PLA) to fabricate composite membranes and examine the differences between the two methods. We collected the electrospun fibers on a grounded rotating drum with varying speeds to prepare membranes with varying fiber alignments. By stacking two membranes with aligned fibers, we made membrane with special direction. We used biaxial mechanical testing to examine the mechanical properties. The results showed that when the fibers were better aligned, the difference in stiffness between the two-axis of the membrane were greater. However, the membrane of the two-axis mechanical properties in off-axis fiber angles, 30° was the same. The stiffness of membranes with highly aligned fibers with off-axis fiber angles, 45° is higher than that of membranes the moderately aligned fibers with off-axis fiber angles, 45°. The composite membranes made by the methods had significantly different mechanical properties even with the same composite ratio. The mechanical properties of the composite membrane made by blend electrospinning were closer to PLA than the composite membrane made by co-electrospinning membranes.

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