| Property | Value |
|---|---|
| Temperature range | -30 °C to +125 °C |
| Hardness | 50–90 Shore A |
| Best at | Ozone, weather, oxidising acids, colour stability, flame |
| Contains fluorine | No |
What it does that neoprene does not
CSM resists strong oxidising chemicals, concentrated acids, and prolonged UV better than neoprene, and it holds colour rather than chalking. For a coloured outdoor part or a lining that meets an oxidiser, that combination is the reason the family exists. It is also inherently flame-resistant from the chlorine in the polymer, without an additive package.
Where neoprene is the balanced all-rounder, CSM is the weather-and-chemistry specialist that gives up some low-temperature flexibility and some cost to get there.
Supply, and being honest about it
DuPont ceased Hypalon production in 2010. CSM is still manufactured, but the supply base is narrower than it was and lead times and pricing behave accordingly. For a new design, we will usually price CPE alongside it and tell you plainly where the substitution holds and where it does not. For an existing part with a qualified CSM spec, we will source it rather than push you into a requalification you did not ask for.
The two mistakes buyers make
The first is treating CSM and CPE as drop-in equivalents. They overlap on weather and flame and diverge on oxidiser resistance and colour retention. If those were the reasons for the original spec, the substitution needs test data behind it.
The second is the low-temperature limit. CSM stiffens around -30 °C, earlier than most buyers expect from a weathering material. Outdoor does not automatically mean cold-capable.
Typical uses
- Chemical hose linings and tank linings
- Roofing and outdoor sheet
- Coloured parts with long UV exposure
- Oxidising acid service
- Flame-resistant industrial parts