Electrospinning has acquired intense recent interest as a means of advancing filtration, tissue engineering, and catalysis. As a part of this evolution, better characterization of electrospinning conditions has been identified as a variable that can improve performance. We use a unique realization of laser micrometry to reveal previously unknown porosity trends within electrospun poly(ε-caprolactone) (PCL) deposited onto a cylindrical mandrel. Electrostatic charging of two PCL-based solutions took place in N₂ at 0 and 50%RH under three collector biases (−5, 0, and +5 kV). At 0%RH, all three gave rise to porosity values of 85–95%, where 95% occurred at the edges of +5 kV; mid-point values were a relatively constant 86–90%. Increases to 50%RH at –5 kV caused edge porosity values of ~56%; mid-point values were ~91% due to a well-defined ‘texture.’ The addition of higher dielectric constant Rose Bengal (RB) caused minor porosity changes at 0%RH, but dramatic changes at 50%RH; mid-points were as low as 12%; edge values reached >80% before decreasing to ~60%. Dense fiber agglomerations were present due to RB's effect on surface charge migration and decreased fiber repulsion along with deposit relaxation likely due to increased solvent retention. Multi-needle depositions of separate PCL and PCL-RB solutions at 0%RH produced a visually uniform, ~90% porous deposition. However, RB analysis showed separated contributions containing either RB-rich or RB-poor fibers. At 50%RH, midpoint porosities decreased to 0% and similar RB-poor or RB-rich regions occurred where 0% was associated with RB likely due to jet segregation due to differences in the grounding ability of PCL versus PCL-RB solutions. This analysis captures variations in through-thickness porosity to provide unprecedented detail regarding conditional effects on electrospun products.

电纺丝作为一种促进过滤，组织工程和催化作用的手段，最近已引起人们极大的兴趣。作为这一发展的一部分，人们已经更好地表征了静电纺丝条件，认为它可以改善性能。我们使用激光测微技术的独特实现来揭示沉积在圆柱心轴上的电纺聚（ε-己内酯）（PCL）中以前未知的孔隙率趋势。在N _2中对两种基于PCL的解决方案进行静电充电在三个集电极偏置电压（-5、0和+5 kV）下，在0和50％RH的条件下。在相对湿度为0％时，所有这三个值的孔隙率值都在85-95％之间，其中95％出现在+5 kV的边缘；中点值相对恒定为86-90％。在–5 kV下增加到50％RH会导致〜56％的边缘孔隙率；由于定义明确的“纹理”，中点值为〜91％。添加较高介电常数的玫瑰红（RB）在0％RH时会引起较小的孔隙率变化，但在50％RH时会发生剧烈变化。中点低至12％；边缘值达到> 80％，然后降至〜60％。由于RB对表面电荷迁移的影响，纤维排斥力降低以及可能由于增加的溶剂保留而引起的沉积物松弛，导致存在密集的纤维团聚。在0％RH的情况下，多针分别沉积PCL和PCL-RB溶液会产生视觉上均匀的效果，约90％的多孔沉积。但是，RB分析显示包含富含RB或缺乏RB的纤维的分离贡献。在50％RH时，中点孔隙率降低至0％，并且出现了类似的RB贫乏或RB富集区域，其中0％与RB相关，这可能是由于PCL与PCL-RB解决方案的接地能力差异而导致的射流偏析。该分析捕获了整个厚度孔隙率的变化，从而提供了有关电纺产品的条件效应的前所未有的细节。