isolant de liège

OBS: Les isolants peuvent être classés, selon leur origine, en 3 catégories : 1er les matériaux d'origine minérale [...]; 2e les matériaux d'origine végétale (liège, balsa, paille, varech); 3e les matériaux plastiques alvéolaires [...]
OBS: Le tronc du chêne-liège est recouvert d'une écorce épaisse, récoltée pour fabriquer des bouchons ou des matériaux isolants.
OBS: Cahier Enviroguide chlore, chap. 4.1.4.

CONT: Cork Insulation. Cork is the outer bark of an oak tree that flourishes only in the area surrounding the western Mediterranean Sea. Instead of being fibrous in structure, the bark of the cork oak is composed of tiny cells, so small that there are 200 million of them to every cubic inch of cork bark. These tiny cells give cork a high resistance to the passage of heat. Each cell is filled with still air, and next to a vacuum, still air is the best insulation known. Because the cells are so tiny, no convection currents in the air can be established to reduce its insulation properties. The cellular structure gives the material its high degree of natural moisture resistance. Each tiny cork cell is a perfect geometric shape, having 14 sides. The volume of cork includes more than 75% air. Its thermal conductivity is 0.26 Btu per square foot per hour per degree temperature difference at 60 degrees F. (metric), and 0.30 Btu per square foot per degree temperature difference at 180 degrees F (metric).
OBS: cork insulation: term officially approved by the Lexicon Project Committee (New Brunswick).