Toward high‐strength bio‐based polyamide 56 (PA56) fiber, we first in situ precipitate graphene oxide (GO), adipic acid and 1,5‐pentanodiamine together by reaction crystallization in ethanal to obtain PA56 salt/GO particles with well dispersed GO, then prepare PA56/GO nanocomposite with PA56 salt/GO via solvent‐free polymerization including solid‐state prepolycondensation and melt polycondensation. Finally, PA56/GO nanocomposite fiber is prepared by extrusion drawing. With 0.2 wt% GO, the tensile strength of PA56/GO fiber reaches 1050 MPa, which is 3.3 times that of pure PA56 fiber. Furtherly, we add PA56/GO with high GO content to commercial PA56 to prepare the hybrid fiber, of which the tensile strength reaches 1248 MPa. The great improvement is mainly due to the good dispersion of GO in the whole process, which increases the heterogeneous nucleation in favor of higher and oriented PA56 crystallization.Highlights Bio‐based PA56/GO nanocomposite fiber with 1.2 GPa strength has been prepared. PA56 salt/GO particles with well‐dispersed GO are in situ precipitated. Solvent‐free polymerization is used instead of solution melt polymerization. Well‐dispersed GO results in high and oriented crystallinity of PA56/GO fiber. Tensile strength of PA56/GO fiber is 2.3 times that of commercial PA56 fiber.

中文翻译：

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通过原位沉淀和无溶剂聚合制备强度为 1.2 GPa 的生物基 PA56/GO 纳米复合纤维

针对高强度生物基聚酰胺56（PA56）纤维，我们首先通过在乙醇中反应结晶，原位沉淀氧化石墨烯（GO）、己二酸和1,5-戊二胺，获得GO分散良好的PA56盐/GO颗粒，然后以PA56盐/GO为原料，通过固相预缩聚和熔融缩聚等无溶剂聚合制备PA56/GO纳米复合材料。最后通过挤压拉伸制备PA56/GO纳米复合纤维。添加0.2 wt% GO后，PA56/GO纤维的拉伸强度达到1050 MPa，是纯PA56纤维的3.3倍。进一步，我们在商用PA56中添加高GO含量的PA56/GO制备混合纤维，其拉伸强度达到1248 MPa。巨大的改进主要是由于GO在整个过程中良好的分散，增加了异相成核，有利于PA56更高和定向的结晶。亮点 制备了强度为1.2 GPa的生物基PA56/GO纳米复合纤维。 具有良好分散的 GO 的 PA56 盐/GO 颗粒是原位沉淀的。 采用无溶剂聚合代替溶液熔融聚合。 良好分散的 GO 导致 PA56/GO 纤维具有高且定向的结晶度。 PA56/GO纤维的拉伸强度是商用PA56纤维的2.3倍。