Liu X, Aho J, Baldursdottir S, Bohr A, Qu H, Christensen L P, Rantanen J, Yang M
Department of Pharmacy, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark.
Department of Chemical Engineering, Biotechnology and Environmental Technology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark.
Int J Pharm. 2017 Aug 30;529(1-2):371-380. doi: 10.1016/j.ijpharm.2017.06.086. Epub 2017 Jul 8.
The aim of this study was to investigate the influence of polymer molecular structure on the electrospinnability and mechanical properties of electrospun fibrous mats (EFMs). Polymers with similar molecular weight but different composition ratios (lactic acid (LA) and glycolic acid (GA)) were dissolved in binary mixtures of N,N-dimethylformamide (DMF) and tetrahydrofuran (THF). The intrinsic viscosity and rheological properties of polymer solutions were investigated prior to electrospinning. The morphology and mechanical properties of the resulting EFMs were characterized by scanning electron microscope (SEM) and dynamic mechanical analysis (DMA). Sufficiently high inter-molecular interactions were found to be a prerequisite to ensure the formation of fibers in the electrospinning process, regardless the polymer composition. The higher the amount of GA in the polymer composition, the more ordered and entangled molecules were formed after electrospinning from the solution in THF-DMF, which resulted in higher Young's modulus and tensile strength of the EFMs. In conclusion, this study shows that the mechanical properties of EFMs, which depend on the polymer molecule-solvent affinity, can be predicted by the inter-molecular interactions in the starting polymer solutions and over the drying process of electrospinning.
本研究的目的是探究聚合物分子结构对电纺纤维毡（EFM）的可电纺性和力学性能的影响。将分子量相似但组成比例不同（乳酸（LA）和乙醇酸（GA））的聚合物溶解于N，N - 二甲基甲酰胺（DMF）和四氢呋喃（THF）的二元混合物中。在电纺丝之前研究了聚合物溶液的特性粘度和流变性能。通过扫描电子显微镜（SEM）和动态力学分析（DMA）对所得EFM的形态和力学性能进行了表征。发现足够高的分子间相互作用是确保在电纺丝过程中形成纤维的先决条件，而与聚合物组成无关。聚合物组合物中GA的含量越高，从THF - DMF溶液中电纺丝后形成的分子排列越有序且缠结程度越高，这导致EFM的杨氏模量和拉伸强度越高。总之，本研究表明，EFM的力学性能取决于聚合物 - 溶剂亲和力，可通过起始聚合物溶液中的分子间相互作用以及电纺丝干燥过程来预测。
