Effect of Modified Natural Filler O-Methylene Phosphonic κ-Carrageenan on Chitosan-Based Polymer Electrolytes

Abstract

The potential for using O-methylene phosphonic κ-carrageenan (OMPk) as a filler in the chitosan-based polymer electrolyte N-methylene phosphonic chitosan (NMPC) was investigated. OMPk, a derivative of κ-carrageenan, was synthesized via phosphorylation and characterized using infrared spectroscopy (IR) and nuclear magnetic resonance (NMR). Both the IR and NMR results confirmed the phosphorylation of the parent carrageenan. The solid polymer electrolyte (SPE)-based NMPC was prepared by solution casting with different weight percentages of OMPk ranging from 2 to 8 wt %. The tensile strength of the polymer membrane increased from 18.02 to 38.95 MPa as the amount of OMPk increased to 6 wt %. However, the increase in the ionic conductivity did not match the increase in the tensile strength. The highest ionic conductivity was achieved with 4 wt % OMPk, which resulted in 1.43 × 10−5 Scm−1. The κ-carrageenan-based OMPk filler strengthened the SPE while maintaining an acceptable level of ionic conductivity.

Hybrid Composite Membrane of Phosphorylated Chitosan/Poly (Vinyl Alcohol)/Silica as a Proton Exchange Membrane

“…The amine deformation peaks shifted to lower frequencies, from 1643 cm −1 and 1548 cm −1 in chitosan to 1632 cm −1 (antisymmetric deformation) and 1536 cm −1 (symmetric deformation) in NMPC; this result indicated the protonation of the chitosan amine as there was a hydrogen substitution to the methylene phosphonic groups that made it a tertiary amine and involved both peaks attributed to NH 3 + groups [ 12 , 39 ]. The new bands at 1243 cm −1 and 943 cm −1 were ascribed to P=O and P-OH stretching bands, whereas the peaks at 1470 cm −1 and 1380 cm −1 were assigned to –CH 2 – vibrations of the methylene phosphonic groups in the molecule [ 12 , 39 , 41 ]. Moreover, the new peak at 2386 cm −1 indicated the P–H stretching of phosphonic groups, and the existence of these new peaks proved the addition of methylene phosphonic groups into chitosan.…”

“…Moreover, the new peak at 2386 cm −1 indicated the P–H stretching of phosphonic groups, and the existence of these new peaks proved the addition of methylene phosphonic groups into chitosan. In addition, the strong bands with high intensities at 1057 cm −1 and 1027 cm −1 implied that C–O stretching overlapped with P–OH stretching; thus, according to the FTIR analysis, the resultant NMPC was successfully synthesized through a phosphorylation method [ 39 , 41 ].…”

Synthesis and characterizations of o-nitrochitosan based biopolymer electrolyte for electrochemical devices

“…Comparison between four functional groups, NO 2 - > PO 3 3- > COO - > SO 3 2- were discussed. It was reported that nitro group had the highest electronegativity thus produced the highest conductivity value, 5.22 ×10 −6 S cm -1 for the blank system compared to PO 3 -3 , COO - and SO 3 -2 which their conductivity values were 3.6 ×10 −6 S cm -1 [17], 4.0 ×10 −7 S cm -1 [13] and 5.0 × 10 −9 S cm -1 [18], respectively. In this work, O-nitrochitosan which was synthesized in different ratios of sodium hydroxide was studied.…”

The role of disaccharides as a plasticizer in improving the interaction between chitosan chain based solid polymer electrolytes (SPEs)

“…6 However, chitosan-based SPEs showed a very low ionic conductivity between 10 −9 and 10 −10 siemens per centimetre (S cm −1 ). 7 According to gel theory, the rigidity and brittleness of a chitosan film are inherent qualities attributable to its three-dimensional network stabilised by strong polymer–polymer interactions, specifically hydrogen bonds. 8…”