Signifacant Improvement Of Polyamide 6 Fiber By Applying Surface Modified Graphene Oxide

Polyamide 6(PA6)fiber is one of the varieties with excellent performance and wide application in synthetic fibers.In recent years,higher requirements have been placed on the performance of PA6 fibers with the rapid development of high-performance fibers.Graphene oxide(GO),as a nanosheet material,has received wide attention due to its unique structure and excellent performance.in current research,it has become a hot topic that add GO to polymer materials to increase the added value of composite materials.Therefore,a new type of composite fiber is prepared,which retains the characteristics of PA6 and also has the excellent characteristics of GO by using GO to modify PA6 fiber.In this paper,GO was prepared by Hummers method,and the prepared GO was analyzed from the aspects of chemical composition,chemical structure,thermal stability and morphology.Different modified graphene oxides A-GO and PEA-g-GO were prepared by modification with dodecylamine(DA)and polyetheramine(PEA).Then,PA6/A-GO composite fibers with different mass ratios were prepared by melt spinning,and the morphology,thermal properties,crystallization properties and mechanical properties of the fibers were investigated.Finally,0.1% PA6/PEA-g-GO composite fiber was prepared by melt spinning method,and compared with 0.1% PA6/A-GO composite fiber.Differences in the effects of small molecular and polymer modified GO on the properties of PA6/GO composite fibers.The specific research results are as follows:1.The GO was prepared by Hummers method.The morphology and structure of GO were characterized.The results showed that GO was successfully prepared.GO has a high degree of oxidation,and its surface is rich in oxygen-containing groups.The single-layer GO sheet is pleated,and the number of layers of GO in the GO water dispersion is not more than three.2.Through the characterization of A-GO and PA6/A-GO composites fibers,the results indicate that the DA is successfully grafted onto GO and the layer spacing of A-GO increased by 0.37 nm compared with GO.A-GO has good interface interaction with matrix PA6,which can achieve more uniform dispersion.A-GO plays a role of heterogeneous nucleating agent in the crystallization of PA6 fibers,which promotes the crystallization of nylon 6 fiber and induces the crystal form transformation,from ? form to ? form.Comparing to pure PA6 fiber,the 0.5wt% thermal weight loss temperature of PA6/A-GO composites fibers is enhanced by 6.1-8.9 ?,which manifested well thermal stability.When the content of A-GO is as low as 0.1wt%,the tensile strength of composite fiber is improved to 1.4 times of pure PA6 fibers.3.Through the characterization of PEA-g-GO and 0.1%PEA-g-GO/PA6 composites fibers,the results indicate that the PEA is successfully grafted onto GO.Polymer PEA with long molecular chain has better peeling effect on GO sheet than DA.The GO uniformly dispersed in the PA6 matrix greatly improved the interfacial adhesion between the filler and the matrix after PEA modification;PEA-g-GO showed better promotion of PA6 fiber crystallization and improved PA6 fiber thermal stability than A-GO.The tensile strength and elongation at break of 0.1% PEA-g-GO composite fiber increased by 0.5 cN/dtex and 115.5%,compared with pure PA6 fiber,showing excellent reinforcement.The elongation at break of 0.1% PEA-g-GO composite fiber is increased by 147.8% compared with 0.1% A-GO composite fiber,which is 2.3 times that of pure PA6 fiber.