<I>In-Situ</I> Preparation and Characterization of Acid Functionalized Single Walled Carbon Nanotubes with Polyimide Nanofibers

Abstract

Nanofiber composites (Polyimide/f-SWCNT) of Pyromellitic dianhydride, 4,4'-Oxydianiline, and 4,4'-(4,4'-isopropylidene diphenyl-1,1'-diyl dioxy) dianiline (PMDA-ODA/IDDA) and surface-functionalized single walled carbon nanotubes (f-SWCNT) were made by electrospinning a solution of poly(amic acid) (PAA) containing 0-2 wt% f-SWCNT followed by thermal imidization. X-ray photoelectron spectroscopy spectra verified the oxidation of SWCNT surface after acid treatment, and indicated possible hydrogen bonding interactions between the f-SWCNTs and polyamic acid. High-resolution scanning electron microscopy images showed the average diameter of nanofibers to be below 150 nm, and transmission electron microscopy images showed that SWCNTs were aligned inside the polymer nanofiber. In thermogravimetric analysis, all composites showed increased thermal stability with increasing f-SWCNT content compared to neat PI. Storage modulus also increased from 124 MPa to 229 MPa from neat PI to 2% f-SWCNT composite.

Unveiling the potential of Pd(II)‐covalent organic polyimide framework in Suzuki coupling reactions: A study on synthesis, characterization, and catalytic efficiency

“…Additionally, the bands at 1367, 1117, and 728 cm −1 indicate C‐N‐C imide axial tension, C‐N‐C imide transverse stretching, and imide C‐N‐C out of plane bending, respectively. These specific absorption bands provide confirmation of the successful formation of a polyimide structure, indicating the conversion of the product to an imide 64,65 . Furthermore, the presence of a peak at 528 cm −1 suggests the existence of chlorides bound to palladium, providing evidence for the formation of the complexes 42…”

“…These specific absorption bands provide confirmation of the successful formation of a polyimide structure, indicating the conversion of the product to an imide. 64,65 Furthermore, the presence of a peak at 528 cm À1 suggests the existence of chlorides bound to palladium, providing evidence for the formation of the complexes. 42 After undergoing thermal condensation, the X-ray diffraction (XRD) patterns (depicted in Figure 2) exhibited clear diffraction peaks with well-defined profiles, indicating that the materials possessed satisfactory crystallinity.…”