Aramid based on poly (p‐phenylene terephthalamide) (PPTA) is widely concerned as high‐performance materials. Herein, copolymerized aramid nanofibers (CANFs) were prepared for the first time by a direct bottom‐up polymerization method without additives. Three kinds of third monomers of m‐phenylenediamine, 4,4′‐diaminodiphenyl ether, and 2,5‐dichloro‐1,4‐phenylenediamine were separately copolymerized in PPTA and transformed into nanofiber dispersions in water medium. The characterization results revealed the relationship between the morphology of products and the structure as well as dosages of the different kinds of monomers, which was explained by the influence on conjugate regularities of the PPTA molecules. Furthermore, CANFs were used to build aramid paper blended in pure PPTA nanofibers, and the mechanical and insulation properties of composite paper were improved significantly, which would be of potential use as the new building block for aramid composite materials.

中文翻译：

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芳族聚酰胺纳米纤维的自下而上合成：共聚的影响

基于聚对苯二甲酰对苯二甲酰胺（PPTA）的芳纶作为高性能材料受到广泛关注。在此，共聚芳纶​​纳米纤维（CANFs）首次通过无添加剂的直接自下而上聚合方法制备。m的三种第三单体苯二胺，4,4'-二氨基二苯醚和2,5-二氯-1,4-苯二胺分别在PPTA中共聚，并转化为在水介质中的纳米纤维分散体。表征结果揭示了产物的形态与不同单体的结构和剂量之间的关系，这可以通过对PPTA分子的共轭规则性的影响来解释。此外，CANFs被用于制造掺入纯PPTA纳米纤维中的芳纶纸，并且复合纸的机械和绝缘性能得到了显着改善，将有可能用作芳纶复合材料的新组成部分。