Large-scale fabrication of polyimide fibers containing functionalized multiwalled carbon nanotubes via wet spinning
Functionalized multiwalled carbon nanotubes (f-MWNTs)/polyamic acid (PAA) solution was prepared via in situ polymerization. Transmission electron microscopy conformed the homogeneous dispersion of f-MWNTs in the polymer matrix. The diffusion rate of N,N-dimethylacetamide in f-MWNT/PAA solution into water shows a significant acceleration upon f-MWNT loadings. PAA composite fibers containing various loadings of f-MWNTs were produced by traditional wet-spinning process, and then the precursor fibers were converted to corresponding polyimide fibers via thermal imidization. Scanning electron microscopy, atomic force microscopy and X-ray scattering were employed to characterize the composite fibers. The thermal stability of polyimide fibers shows an obvious improvement with the incorporation of f-MWNTs. Meanwhile, f-MWNTs hinder the motivation of macromolecular chains, resulting in a reduced heat-shrinkage of the composite fibers. Exceptional enhanced mechanical properties of composite fibers were obtained due to the introduction of f-MWNT nanofillers.
