VARMEISOLERINGSMATERIALE AF SYNTAKTISK TYPE, APPARAT OG FREMGANGSMAADE TIL DETS FREMSTILLING OG ISOLERINGSMIDDEL OMFATTENDE ET SAADANT MATERIALE

摘要

A heat-insulating material of the syntactic type comprising a filler of hollow glass microspheres embedded in a matrix, and fabrication method. The matrix is selected from such elastomers as natural rubber, polychloroprene, styrene-butadiene copolymers (SBR), butadiene-acrylonitrile copolymers (NBR), polynorbornenes, ethylene-propylene-diene monomers (EPDM), butyl rubbers and the like. For the fabrication of the material, the hollow glass microspheres are incorporated into a matrix in liquid or pulverulent state, and the microspheres and the matrix are mixed together without applying large shearing forces and finally a cross-linking treatment is performed. The material is usable particularly for insulating underwater pipelines for the transportation of gas or oil from off- shore oil fields or for district heating systems. <IMAGE>