Polyimide nanohybrid films with electrochemically functionalized graphene

Abstract

Graphite was functionalized electrochemically in a potassium fluoride solution and used to prepare polyimide (PI)/graphene nanohybrid films. The as-made electrochemically fluorinated graphene (EFG) was used to prepare nanohybrid films with colorless PI, which was synthesized from 4,4 ′ -(hexafluoroisopropylidene) diphthalic anhydride and bis(trifluoromethyl) benzidine by in situ polymerization. The surface functionalization of graphite was characterized by powder XRD, TEM with energy dispersive X-ray spectroscopy elemental mapping, X-ray photoelectron spectroscopy, Raman spectroscopy, and TGA. The microstructure of the films was characterized by Fourier transform IR spectroscopy, XRD and SEM. The film properties were measured using a universal testing machine, TGA, dynamic mechanical analysis, four-point probe, UV-visible spectroscopy and water contact angle analysis. EFG improved the tensile strength and modulus of the nanohybrid films by 20% and 50%, respectively. The glass transition temperature and electrical conductivity of the nanohybrid films were 12 ∘ C and nine orders of magnitude higher than those of the neat PI film, respectively. The nanohybrid film maintained 80% optical transmittance even after the addition of 0.1 wt% EFG.

Synergistic effects of boron nitride sheets and reduced graphene oxide on reinforcing the thermal conduction, SERS performance and thermal property of polyimide composite films

“…24,25 Large amount of research have been done on preparing GO/PI films with high performance properties. [25][26][27][28] Significant efforts have been reported to indicate that the thermal conductive property of PI is affected by the interface and the interfacial thermal resistance between fillers and polymer matrix. 29 However, the effect of single filler on the increase of the material was always limited.…”

“…Graphene perform well in enhancing the TC values of composites synergistically because graphene presents an ultrahigh TC value (~5000 Wm −1 K −1 ) 24,25 . Large amount of research have been done on preparing GO/PI films with high performance properties 25–28 . Significant efforts have been reported to indicate that the thermal conductive property of PI is affected by the interface and the interfacial thermal resistance between fillers and polymer matrix 29 .…”

Amine-Functionalized Reduced Graphene Oxide/Polyimide Nanocomposite as a Material with High Dielectric Constant and Thermal Resistance

“…Moreover, due to the inevitable contact of conductive fillers after the percolation threshold, the dielectric loss of those composite materials also increased. Carbon-based conductive materials such as carbon nanotube (CNT) − and graphene − possess very high electrical conductivity and can be modified by reagents and thus can form chemical connections with integrated polymer matrix. They can improve the dielectric properties of the composite material at a considerably low integration ratio.…”

Enhanced toughness and gas permeabilities of polyimide composites derived from polyimide matrix and flower‐like polyimide microparticles

“…[6][7][8][9][10] According to some reported literature, there have been many kinds of particles or fillers used for PI modification, including graphene, graphene oxide, carbon nanotubes, organic covalent framework (COF) materials, metal organic framework materials, polymer, metal and oxide particles, etc. [11][12][13][14][15][16][17][18][19][20] Under the combined action of functional particles and appropriate composite methods, the properties of PIs, including mechanical, thermal, electrical, gas separation, tribological properties, and atomic oxygen resistance, have been obviously improved. [21][22][23][24][25][26][27][28][29] It is well known that the interfacial interaction between the organic matrix and the fillers directly affects the properties of the composites.…”