Effect of phosphoric acid molarity on the structural, thermal, mechanical, and electrical properties of polyimide/polyaniline nanocomposites

Abstract

In this paper, we used two monomers, 3,3',4,4'-benzophenone tetracarboxylic dianhydride (BTDA) and m,m'-diaminobenzophenone (m, m’-DABP), to produce polyamide acid and then converted it to polyimide (PI). The effects of phosphoric acid (H3PO4) molarity (1, 2, and 3 M) on the structural, thermal, mechanical, and electrical characteristics of the polyimides/polyaniline (PI/PANI) nanocomposites were studied. Two sharp reflection peaks were developed by the addition of PANI to PI. When 3 M H3PO4 is added, the crystalline sharp peak loses some of its intensity. The complex formation of PI/PANI-H3PO4 was confirmed by Fourier transform infrared spectroscopy studies. The surface morphologies of the H3PO4 complex with nanocomposites were investigated by using a scanning electron microscope. From differential scanning calorimetry studies, the glass transition temperatures of nanocomposites decrease dramatically with an increase in H3PO4. Microhardness, flexural strength, and young modulus all dropped as acid molarity increased, although elongation at break increased as H3PO4 molarity increased. After the addition of H3PO4, a drop in the dielectric constant and an increase in ionic conductivity were observed.

Optical transparency of electrospun nanofibrous membranes: A study on influencing parameters

“…24 It should be noted that the crystallinity of a polymeric material can be altered by heat treatment. [25][26][27] When the temperature rises above the polymer glass transition temperature, the polymer crystallinity is reduced. 28,29 The heat treatment of the produced electrospun nanofibers is proven feasible to increase its transparency.…”

“…In addition, the transparent nanofibrous membrane could serve as a filter in a window screen, or other air filtration systems, which allows light transmission 8 . Furthermore, the transparent nanofibers can be applied as an anti‐reflective coating layer in the outer surface of a solar cell which maximize incoming light by reducing reflections for enhancing the energy conversion efficiency 9–12 …”

“…The amorphous polymer is largely consisted of randomly distributed polymer chains which have less boundaries to reflect light compared to a crystal structure 24 . It should be noted that the crystallinity of a polymeric material can be altered by heat treatment 25–27 . When the temperature rises above the polymer glass transition temperature, the polymer crystallinity is reduced 28,29 …”

Development of novel composite bipolar plates using surface‐modified conductive carbon filler materials for polymer electrolyte membrane fuel cells

“…36 Conductive polymers like polyaniline (PANI), polypyrrole (PPy), polythiophene (PTH), and so forth, can also be used as binders. 37,38 Epoxy resin (ER), a standard thermosetting resin, can be used to fabricate PCCBP as it has low density, low viscosity and attractive mechanical properties. Zakaria et al 19 used ER as a binder to develop PCCBP.…”

“…Thermosetting polymer resins have lower viscosity at higher temperatures compared to thermoplastic polymer resins, which permits adding more conductive filler materials 36 . Conductive polymers like polyaniline (PANI), polypyrrole (PPy), polythiophene (PTH), and so forth, can also be used as binders 37,38 …”