Synthesis of proton-conducting membranes based on sulfonated polystyrene and bacterial cellulose

Abstract

Synthesis of composite material based on sulfonated polystyrene and bacterial cellulose as a proton membrane has been carried out. In this study, the membrane was made with the variations mass ratio of sulfonated polystyrene : bacterial cellulose 1,5: 3,5, 2,5: 2,5, 3,5: 1,5. The previous step was sulfonation of polystyrene, in which the polystyrene used is styrofoam from electronic goods packaging waste. Polystyrene in this case styrofoam is sulfonated using the sulfonating agent trimethylsilyl chlorosulfonate. The membranes have characterized by analyzing of functional groups, proton conductivity, cation exchange capacity, and degree of swelling. The FTIR spectrum showed that the sulfonated polystyrene-bacterial cellulose composite material was successfully synthesized which was shown at the peak at wave number 1124.767 cm-1 which was a SO3 stretching vibration. The peak at wave number 962-1150 cm-1 was assigned the stretching of CO vibrations for C-OC and C-OH which indicates cellulose glycosidic bonds. The highest Cation Exchange Capacity (CEC) value and proton conductivity were in the composite membrane: bacterial cellulose mass ratio 3,5: 1,5, the CEC value 2.25 meq/g and the proton conductivity value 1.176 x 10-6 S/cm2. This result shows that the sulfonated polystyrene-cellulose bacterial composite membrane has the ability to deliver protons so that it has the potential to be developed as a fuel cell membrane.