Hydrogel biopolymers such as carrageenan and chitosan can be used as filters and as electrolyte polymers in fuel cells, batteries, capacitors, and solar cells. Carrageenan is known for its ability to increase membrane porosity, while chitosan can influence the hydrophobicity properties of membranes. Due to the differences in their abilities and properties, it is necessary to know the impact of the chitosan/carrageenan ratio to the tensile strength, thermal stability, water absorption ability, conductivity, ion exchange capacity, and the permeability of methanol. Four composite hydrogels consisting of chitosan, carrageenan, polyvinyl alcohol, and Multi Walled Carbon Nanotubes (MWCNTs) in ratios of chitosan/carrageenan of 0.2, 0.33, 0.5, and 0.71 were fabricated and characterized. The thermal stability of the hydrogel composites was estimated using a thermogravimetric analysis instrument, resistance was measured analog multimeter, the tensile strength testing follows the American Standard Testing and Material E8, ion exchange capacity measured by acid–base titration, and methanol permeability determined using liquid chromatography method. The average tensile strength is 7.203 MPa and the population standard deviation is 0.395. The thermal properties are not affected by the chitosan/carrageenan ratio, water evaporation and decomposition of the nitrogen functional groups and polymer backbone occurs at 100 ℃ and 250–280 ℃. Ion exchange capacity, water absorption ability and linear expansion ratio decrease with increasing chitosan/carrageenan ratio, methanol permeability increases, and selectivity decreases with an increase in the chitosan/carrageenan ratio. The conductivity at room temperature at a ratio of 0.33 is the smallest and at 0.2 and 0.5 ratios are 0.073 and 0.072 Scm−1.