noun
insulating material
Technical term used in electrical engineering and related fields for materials that prevent the flow of electricity or heat.
この絶縁材料は高温でも性能が落ちません。
This insulating material does not degrade even at high temperatures.
絶縁体 is an insulator (the object or substance itself), while 絶縁材料 refers to the material used for insulation.
Compound of 絶縁 (insulation) and 材料 (material).