composiÇço espumante de baixa perda, processo para produÇço de uma composiÇço espumante de baixa perda, cabo tendo camada espumante de baixa perda e processo para a formaÇço de cabo tendo camada espumante de baixa perda

• Main Authors: CAROLINE VACHON, VIJAI K. CHOPRA, HUGH R. NUDD, MICHEL F. CHAMPAGNE, RICHARD GENDRON, SITARAM RAMPALLI
• Format: Patent
• Language: Portuguese
• Published: 16.04.2013
• Subjects: AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F,C08G; CHEMISTRY; COMPOSITIONS BASED THEREON; COMPOSITIONS OF MACROMOLECULAR COMPOUNDS; GENERAL PROCESSES OF COMPOUNDING; METALLURGY; ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; WORKING-UP

The invention relates to a low loss foam composition and cable, such as a coaxial cable. The foam composition is formed by heating an olefinic polymer, such as a high density polyethylene, medium density polyethylene, low density polyethylene, linear low density polyethylene, polypropylene, or a combination thereof, into a molten state composition, optionally with a nucleating agent. The molten mixture is extruded under pressure through a die with a blowing agent comprising an atmospheric gas, such as carbon dioxide, nitrogen or air, and a co-blowing agent selected from hydrofluorocarbons, hydrochlorofluorocarbons, or perfluoro compounds, such as HFC-134a. The cable is formed by extruding the foam composition onto a signal carrying conductor and sheathing the foam-coated signal carrying conductor in an appropriate conducting shield.