摘要 |
<p>A gaseous resistant tube comprising an inner core of a heat resistant polymeric material, typically cross-linked polyethylene, protected outer layer of impact resistant material and an intermediate layer of non-metalliferous gaseous resistant material, wherein the intermediate layer is bonded to at least one of the inner core and the outer layer by bonding material compatible with each of the materials to be bonded and is sufficiently elastic that it will not delaminate or rupture either itself or the adjoining layer under heat cycling conditions. In a preferred embodiment of the invention, the bonding material is preferably a material different from the layer to which it bonds.</p> |