abstract
The present study discloses a new type of nanocomposite membranes consisting of cross-linked poly(methacryloyloxyethyl phosphate) (PMOEP) and bacterial cellulose (BC) prepared by the in situ free radical polymerization of MOEP within the BC network under green reaction conditions. Homogeneous and translucent PMOEP/BC nanocomposite membranes with 52, 61 and 78 wt% of BC have good thermal and viscoelastic stability up to 180 A degrees C with storage modulus higher than 200 MPa, good mechanical properties (Young's modulus = 7.8-13.5 GPa), and high ion exchange capacity (1.95-3.38 mmol [H+] g(-1)). The protonic conductivity of these nanocomposite membranes increases with increasing PMOEP content and relative humidity (RH), reaching values higher than 0.1 S cm(-1) at 98 % RH, with activation energy close to 15 kJ mol(-1), from room temperature up to 94 A degrees C. These values are comparable to, or higher than, data typically found for a commercial Nafion(A (R)) membrane, further confirming the potential of these proton separator materials as a green alternative for application in fuel cells.
keywords
BACTERIAL CELLULOSE MEMBRANES; FUEL-CELL APPLICATIONS; MICROBIAL CELLULOSE; CONDUCTIVITY; TEMPERATURE; COPOLYMERS; CHITOSAN; SORPTION; PEMFCS; ACID
subject category
Materials Science; Polymer Science
authors
Vilela, C; Gadim, TDO; Silvestre, AJD; Freire, CSR; Figueiredo, FML
our authors
Armando Jorge Domingues Silvestre
Full professor
Carla Vilela
Assistant Professor
Carmen Sofia da Rocha Freire Barros
Coordinating Researcher
Filipe Miguel H Lebre R Figueiredo
Principal Researcher
Tiago Gadim
Research FellowshipGroups
G3 - Electrochemical Materials, Interfaces and Coatings
G4 - Renewable Materials and Circular Economy
Projects
CICECO - Aveiro Institute of Materials (UID/CTM/50011/2013)
Bacterial Cellulose Membranes for Proton Exchange Fuel Cells (EXPL/CTM-ENE/0548/2012)
acknowledgements
This work was developed within the scope of the project CICECO-Aveiro Institute of Materials, POCI-01-0145-FEDER-007679 (FCT Ref. UID/CTM/50011/2013), financed by national funds through the FCT/MEC and when appropriate co-financed by FEDER under the PT2020 Partnership Agreement, CelFuelCel (EXPL/CTM-ENE/0548/2012). The Portuguese Foundation for Science and Technology (FCT) is also acknowledged for a post-doctoral grant to C. Vilela (SFRH/BPD/84168/2012), and research contracts under Investigador FCT to C.S.R. Freire (IF/01407/2012) and F.M.L. Figueiredo (IF/01174/2013).