Preparation of crystalline polyimide nanofibers via solution crystallization
Preparation of crystalline polyimide nanofibers via solution crystallization
复制标题
溶液结晶法制备结晶聚酰亚胺纳米纤维
DOI：
10.1038/s41428-023-00765-w
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发表时间：
2023
期刊：
影响因子：
2.8
通讯作者：
Uchida Tetsuya
中科院分区：
文献类型：
--
作者：
Kumano Shota;Takaki Tomoyasu;Uchida Tetsuya
制备了两种具有不同形貌的结晶聚酰亚胺纳米纤维（PINF）。对芳香族 PI 晶体的晶胞和制备的 PINF 的晶体形貌进行了检查。 PINF-I（长度=305±152nm，直径=12±2nm）是从溶解在浓硫酸溶液中的结晶PI中结晶出来的。从该溶液中分离出所得的PINF-I，并且它在水中不聚集。通过将PINF-I分散在水和叔丁醇(TBA)的混合溶液(水:TBA=≥4:1)中，然后冷冻干燥来制备直径为105±99nm的PINF-II。然后，加热PINF-II以增强其结晶度。热处理后的 PINF-II 的 X 射线衍射和透射电子显微镜研究揭示了 PI 晶体晶胞 [斜方晶系，a= 1.21nm，b= 0.88nm，c= 2.23nm（分子链轴方向）]。热处理后的 PINF-II 的晶体结构表明，制备了高度结晶的 PINF，其中 PI 分子链沿纤维长度方向取向。
Two crystalline polyimide nanofibers (PINFs) with different morphologies were prepared. The crystalline unit cells of the aromatic PI crystals and the crystal morphologies of the fabricated PINFs were examined. PINF-I (lengths = 305 ± 152 nm and diameters = 12 ± 2 nm) was crystallized from crystalline PI dissolved in a concentrated sulfuric acid solution. The resulting PINF-I was isolated from this solution, and it did not aggregate in water. PINF-II with diameters of 105 ± 99 nm was prepared by dispersing PINF-I in a mixed water andt-butanol (TBA) solution (water:TBA = 4:1), followed by freeze-drying. Then, the PINF-II was heated to enhance its crystallinity. X-ray diffraction and transmission electron microscopy studies of the heat-treated PINF-II revealed a PI crystalline unit cell [orthorhombic,a= 1.21 nm,b= 0.88 nm, andc= 2.23 nm (molecular chain axis direction)]. The crystal structure of the heat-treated PINF-II suggested that highly crystalline PINFs were fabricated in which the PI molecular chains were oriented along the direction of the fiber lengths.