Share this page by mail How can I avoid moisture regain in microporous and nanoporous insulators?
Microporous and nanoporous insulators are hygroscopic due to their high specific surface area. Exposure to moisture can increase thermal conductivity and even destroy the structure of the material. Final Advanced Materials therefore recommends encapsulation (aluminium foil) or a hydrophobic coating. Pre-drying (100–200°C) is often required before use to restore performance.
We require a complete description of the application and of the stresses before we can recommend the most suitable product.
Final Advanced Materials' microporous insulators have sub-micron pores, limiting thermal conduction. Nanoporous insulators have even smaller pores (<100 nm), reducing thermal transfers still further. Final Advanced Materials' nanoporous materials offer extremely low thermal conductivity levels (~0.015–0.025 W/m·K to 200°C), although they are more effective than those of microporous materials. However, nanoporous materials are more sensitive to moisture and mechanically much more fragile: they cannot be subjected to mechanical stresses during operation.
The nanoporous panels distributed by Final Advanced Materials have very a low thermal conductivity, with values ranging from 0.015 to 0.025 W/m·K at moderate temperature (200–400°C). At high temperature (>800°C) these values are higher but are still lower than those of more traditional insulators. By comparison, fibrous insulators are generally around 0.1–0.3 W/m·K. The choice of insulator will also depend on its mechanical strength and on the environment.
Yes, the microporous boards offered by Final Advanced Materials can be machined with CNC (milling or cutting). Their low mechanical resistance (often <4 MPa when compressed) requires low speeds and special tools. They cause fine dust, requiring a dust extraction system. Although these composites are not hard, they pose a high risk of scaling and crumbling: loads must therefore be minimised, and stripping of material must be avoided. The resulting powder is very abrasive, and it is therefore essential that a dust extraction system is installed on your machinery. We can machine these materials in our production shop.