Chemical modification and structural rearrangements of polyketone‐based polymer membrane

Abstract

Alternating polyketones constitute a very interesting class of polymers, which can be modified for the preparation of functional polymers. The chemical modification of polyketone using 1,2-diaminopropane was used to prepare a conductive membrane. This paper is focused on the synthesis and structural rearrangements of polyamine for preparing anion-exchange membranes by the solvent casting technique. According to the Paal-Knorr mechanism, 1,4-dicarbonyl of polyketone reacts with 1,2-diaminopropane to form a pyrrole ring along the polyketone backbone. In addition, the so-modified polyamines can undergo structural rearrangements to form N-substituted pyrrole crosslinked with dihydropyridine units. The conversion degree and the N content are quite low. The pathway reactions have been proposed on the basis of 1H-NMR, ultraviolet–visible, and Fourier transform infrared results. Scanning electron microscopy,differential scanning calorimetry, and X-ray diffraction techniques were used to study the morphological, thermal, and structural characteristics of the modified polyketone, as well as the correspondoing membrane. The experimental results indicated that the membrane is a potential candidate for energy conversion technolog

Enhanced OH− Conductivity for Fuel Cells with Anion Exchange Membranes, Based on Modified Terpolymer Polyketone and Surface Functionalized Silica

“…An elemental analysis was carried out using a LECO-CHN628 instrument (Saint Joseph, MI, USA) with a combustion technique to ascertain the nitrogen content per gram in the modified polyketone [26][27][28]. Scanning electron microscopy (SEM) imaging was performing with a Coxem EM-30AX instrument (Coxem, Daejeon, Korea) using secondary electrons (SE) and backscattered electrons (BSE) and operated at 10 kV accelerating voltage.…”

Inorganic‐Organic Hybrid Anion Conducting Membranes Based on Ammonium‐Functionalized Polyethylene Pyrrole‐Polyethylene Ketone Copolymer

“…The derivatives produced in this way still contain PK moieties since the reaction of the PK 1,4-diketone units is statistically random and does not reach completeness even in excess of amine, maintaining some of the original polymer properties. At present, many functionalized polyethylene pyrroles-co-PKs (FPK)with anionic exchange group (ammonium, [12][13][14] pyridinium, [11,15,16] or imidazolium [17,18] ) have been proposed. Their degree of functionalization, or relative number of diketone units converted to pyrrole, which corresponds to the number of functional side chains, can be easily tuned by changing the amine/PK ratio or the reaction conditions (temperature or reaction time).…”

What is Next in Anion‐Exchange Membrane Water Electrolyzers? Bottlenecks, Benefits, and Future

“…A hydroxide conductivity as high as 300 mS cm À 1 was recently reported, exceeding the H + conductivity in PEMs. [57] The most common relevant backbones cited in the literature used for AEMs are: polysulfone, [58] poly(ether ketone), [59] poly(phenylene oxide), [60] fluorinated, [61] polybenzimidazole, [62] polyethylene, [63] polystyrene, [64] polyethylenepyrrole-co-polyethyleneketone, [65][66][67] poly(ethylene-cotetrafluoroethylene), [68] and poly(vinylbenzyltrimethylammonium)-b-poly(methylbutylene) type. [69] Some of these AEM backbones showed excellent performance in AEM-WE.…”