TABLE OF CONTENTS In this chapter, some commercially available products will be described to help the reader in selecting a suitable membrane for a given application and in understanding its function. The manufacturers are reluctant to reveal the exact composition of their products, particularly of the more recently introduced ones. Nevertheless, a description of the older types will help the reader to understand the concepts involved. Web sites of manufacturers (such as www.Nafion.com) provide data on the available membranes and resins.
These films are available in a variety of thicknesses and are typically made of either 1000 or 1100 EW polymer. In the Nafion code, the first two digits indicate the EW and the remaining digit(s) the thickness in mils (1 mil = 25.4 ?m).
The films listed in Table 7.1 are all made from extruded precursor film. More recently, DuPont has discontinued Nafion 112 and instead offers solution cast film of 25 and 50 ?m thickness (NRE211 and NRE212, respectively; see also Appendix C).
| Type | Thickness ( ?m) | Equivalent weight (nominal) | Maximum width (m) |
|---|---|---|---|
| Nafion 105 | 130 | 1000 | 1.22 |
| Nafion 112 | 50 | 1100 | 1.22 |
| Nafion 1135 | 90 | 1100 | 1.22 |
| Nafion 117 | 180 | 1100 | 1.22 |
| Flemion FL-4 | 110 | 890 | |
| Flemion FL-12 | 300 | 920 | |
| Aciplex AC-4 | 110 | 980 | |
| Aciplex AC-12 | 320 | 1080 |
For most industrial electrolysis applications, fabric reinforcement is used to improve the mechanical strength, particularly the...
