ZrO2 enhanced PVA/cashew phenol based polybenzoxazine crosslinked membrane for proton exchange membrane fuel cells

Research on the Structure and Characterization of Composite Membrane: Using cashew phenolic polybenzoxazine (MCBZ) as the matrix, a cross-linked network containing 2-mercaptosuccinic acid side groups was introduced and combined with polyvinyl alcohol (PVA) to form a hydrophilic polymer film. To enhance proton transport and stability, researchers dispersed different mass fractions of nano zirconia (ZrO2 NPs) in the membrane. The structure of the nanocomposite film was characterized by FT-IR, ¹ H NMR, ¹ C NMR, PXRD, FE-SEM, and HR-TEM, confirming the introduction of cross-linked network and nanoparticles.

Key performance data

The research system evaluated the swelling rate (SR), water absorption rate (WU), and ion exchange capacity (IEC).

. In the prepared nanocomposite film, the PVA/MCBZ film containing 5 wt% ZrO2 exhibited the optimal IEC at 1.5 meq/g; The proton conductivity reaches 1.096 × 10 ⁻¹ S/cm at 110 ° C. The Arrhenius curve shows a lower activation energy, indicating that protons are mainly transported through vehicular mechanisms. In terms of stability, Fenton reagent testing at 80 ° C showed a lower degree of chemical degradation of the membrane. In the performance test of fuel cells, the maximum power density of ZrO2/PVA/MCBZ membrane was 0.802 mW/cm ² at a current density of 2.26 mA/cm ², which was higher than the 0.530 mW/cm ² obtained by PVA/MCBZ membrane at 1.19 mA/cm ². Based on the above results, the composite membrane exhibits potential applications in the field of fuel cell membrane materials.

Significance for the polymer additive industry

Although this study focuses on proton exchange membranes, its material design ideas have reference value for the field of electronic and electrical materials.

. Cashew phenolic polybenzoxazine, as an engineering plastic related system, combines hydrophilicity, proton conductivity, and chemical stability through PVA crosslinking and nano ZrO2 reinforcement. In electronic and electrical applications, packaging and potting materials, cables and wires, as well as weather resistance and electrical stability, all require ion transport, heat resistance, and long-term stability of materials. The requirements for flame retardancy and weather stability involved in research usually require the combination of antioxidant and other auxiliary systems to suppress oxidative degradation during processing and use. This work provides a reference experimental basis for the formulation design of engineering plastic based composite films in electrochemical energy devices, and also suggests that the synergistic optimization of nano fillers and cross-linked structures is an important direction to improve the stability of electrical performance.

Information source:Synthesis and Characterization of Polyvinyl Alcohol Cross‐Linked Mercaptosuccinic Acid Pendant Cardanol‐Based Polybenzoxazines Incorporating ZrO2 Nanoparticles for Proton Exchange Membranes， Organized by Herun Chemical.