Rigid cellular materials having a good mechanical strength at low temperatures
Abstract
Abstract RIGID CELLULAR MATERIALS WITH CLOSED CELLS. PREPARED FROM POLYVINYL CHLORIDE AND MANUFACTURED BY COPOLYMERISING AT LEAST ONE VINYLIDENE MONOMER WITH AN ETHYLENIC CARBOXYLIC ACID ANHYDRIDE, BY GRAFTING THIS COPOLYMER ON THE CHAINS OF A POLYVINYL CHLORIDE, BY CROSSLINKING WITH ONE ANOTHER THE GRAFTED COPOLYMERS, BY FORMATION OF TWO AMIDE FUNCTIONS BETWEEN THE ISOCYANATE GROUPS OF A MIXTURES OF POLYISOCYANATES AND THE ACID ANHYDRIDE GROUPS AND BY DECOMPOSING A BLOWING AGENT BY HEAT DURING ALL THESE OPERATIONS; THE MIXTURE OF POLYISOCYANATES CONTAINS AT LEAST 50% BY WEIGHT OF HEXAMETHYLENE DIISOCYANATE/ THEY CAN BE USED WITH ADVANTAGE FOR ALL THE APPLICA- . TIONS WHERE THE RIGID CELLULAR MATERIAL MUST BE EXCELLENT AS REGARDS ITS CAPICITY OF ELONGATION AT VERY LOW TEMPERATURES.
Inventors
- 👤 H Tariel
- 👤 R Guyon
Bibliographic Details
Claims Analysis
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