When it comes to surface protection, continuous membranes have come out on top. The ability to create a bespoke, seamless ‘skin’ to fit any shape far surpasses traditional sheet systems.
However, as Mario Pérez (Quality Department at Krypton Chemical) explains, success depends not only on the product, but also on understanding the chemical processes taking place beneath our feet (or on the roof).
1. Polymer architecture
Why is one membrane elastic and another rigid? It all depends on their molecular structure:
- Long chains: Greater elasticity (ideal for bridging cracks).
- High cross-linking: Greater rigidity (ideal for mechanical strength).
2. The sun’s dilemma: Aromatic or aliphatic?
It is a common mistake to confuse them, but the difference is crucial for the look:
- Aromatics: They turn yellow when exposed to UV rays.
- Aliphatic: Sun-resistant. They are the obvious choice for decorative finishes.
3. Understanding reaction rates
Not all products are applied in the same way because they don’t all ‘set’ at the same rate. Here’s a quick summary:
| Reactive | Curing speed | Method of application |
| Amines (Polyureas) | Ultra-fast (seconds) | Two-component machinery (high pressure and temperature) |
| Polyols (Polyurethanes) | Slow / Moderate | Roller, spray gun or hand mixing |
| Water-based (single-component) | It depends on the humidity/temperature | Reaction with ambient moisture |
4. The invisible factor: Humidity and the weather
In single-component products, water in the air acts as a catalyst for the reaction.
- The higher the temperature, the higher the absolute humidity: at 30°C, the air contains almost twice as much water as at 20°C, which speeds up the drying process.
- The danger of solvents: If you use low-quality solvents or if the wind prevents them from evaporating, the membrane’s structure weakens, causing it to lose its integrity at an alarming rate.
A flawless finish comes from choosing the right product and applying it in accordance with the recommended processing times.
Are you working on a technical project and unsure which system to choose?
Get in touch with us and we’ll help you design the perfect solution for your project.
