O-methylene phosphonic κ-carrageenan as filler for chitosan-based polymer electrolyte

The potential for using O-methylene phosphonic κ-carrageenan (OMPk) as a filler in chitosan-based polymer electrolyte N-methylene phosphonic chitosan (NMPC) is investigated. OMPk, a new derivative of κ-carrageenan, is... [ view full abstract ]

The potential for using O-methylene phosphonic κ-carrageenan (OMPk) as a filler in chitosan-based polymer electrolyte N-methylene phosphonic chitosan (NMPC) is investigated. OMPk, a new derivative of κ-carrageenan, is 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 is prepared by solution casting with different weight percentages of OMPk ranging from 2wt% to 8wt%. The tensile strength of the polymer membrane increased from 18.02 MPa to 38.95 MPa as the amount of OMPk increased to 6wt%. However, the increase in the ionic conductivity did not match the increase in the tensile strength. The highest ionic conductivity is achieved with 4wt% 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.