What is the performance of the proton exchange membrane?

2022-03-29 00:00

What is the performance of the proton exchange membrane?

Evaluation of proton exchange membranes is based on standard performance tests. The performance of the proton exchange membrane is mainly characterized by the following indicators.

(1) Mechanical properties

The mechanical performance test of proton exchange membrane is not much different from that of general materials, and can be tested on a mechanical testing machine.

(2) Ion exchange capacity

The ion exchange capacity refers to the millimolar value of the equivalent exchange of the corresponding ions in the external solution per gram of dry film or wet film. The better the performance of this index, the better the conductivity of the corresponding film.

(3) Water absorption rate

When the proton exchange membrane reaches saturation, the ratio of the water absorption mass to the dry membrane mass is the water content of the membrane.

(4) Permeability of methanol

We know that proton exchange membranes need to act as a separation between fuel and oxidant. For methanol, of course, the lower the permeability, the better.

(5) Electrical performance test

The conductivity of the membrane is particularly important for the proton exchange membrane, because another function of the proton exchange membrane in the fuel cell is to act as an electrolyte, which is an important parameter that determines the performance of the cell. Its conductivity can be obtained through a series of electrochemical experiments.

Block copolymers are widely used in high molecular polymers, and the application of block copolymers in proton exchange membranes has achieved remarkable results. Block copolymers can adjust the chemical composition, molecular weight and volume fraction of the blocks to prepare polymer copolymers with a microphase-separated structure.

As we all know, macromolecules, also known as macromolecules, are actually macromolecules composed of many repeating monomers connected by chemical bonds. These repeating monomers can be one or more, and different monomers have different properties, and can form a variety of different chain structures such as random copolymers, block copolymers, alternating copolymers, and graft copolymers. Among them, block copolymers are characterized in that different monomer sequences form compounds through chemical bonds, different monomer units repel each other, and monomers with the same properties polymerize with each other. This gives such copolymers a special steric appearance. Sulfonated block copolymers are the main research direction of proton exchange membranes. Block copolymer proton exchange membranes have higher proton conductivity, lower methanol permeability and better mechanical stability. Although multiblock sulfonated polymers are designed to control the length and composition of the blocks, they are not easy to synthesize. It is obtained by continuous polymerization of sulfonated oligomers and non-sulfonated oligomers. The synthesis route is prolonged and the reactivity is not high. Therefore, it is particularly important to optimize its preparation process.

I believe that through the above introduction, you also have a certain understanding of proton exchange membranes. If you want to know more about proton exchange membrane, please contact us. We have many years of experience in this industry.

总 机: 516-261-9521

总 机: xmsantung@163.com