Inorganic-Organic Hybrid Materials: Diacetylene-Siloxanes as Radiation Resistant Electrical Insulators for Plasma Fusion Confinement Systems
DOE Phase II Contract DE-FG03-01ER83235/A002
Composite electrical insulation systems for superconducting magnet coils for fusion reactors typically include epoxy matrix materials. These epoxy resins exhibit excellent processing characteristics (low viscosity and long working life), mechanical and electrical strength, and radiation tolerance, including low radiation induced gas evolution rates. Historically, radiation resistant polymers have not exhibited suitable processing characteristics for fabrication of large magnet structures. The overall research program was directed toward the development, characterization, and demonstration of a new resin system for cryogenic radiation applications.
During the course of the Phase I research project, diacetylene-siloxane polymeric systems were investigated for processing characteristics, radiation tolerance and mechanical performance. Several polymer compositions were prepared and screened by evaluation of their radiation induced gas evolution rate, processing characteristics, and composite mechanical performance.
This program synthesized, characterized and developed a new inorganic-organic polymeric system based on diacetylene-siloxanes for use in fabrication of glass fiber reinforced polymer matrix composites. The composites are used as electrical insulators for superconducting magnet coils in fusion reactors. The polymeric system was optimized and critical properties of composites measured. Radiation tolerance was evaluated by exposure of samples to several radiation species.
In Phase I, inorganic-organic polymeric systems based on diacetylene-siloxanes were prepared and evaluated for use as matrix materials for fabrication of glass fiber reinforced composites. The initial viscosity, working life, and radiation resistance of the polymeric systems were evaluated. Several composites were fabricated and their short-beam shear strength determined.
The Phase II program fully characterized the properties of the diacetylene-siloxane polymers, including critical cryogenic composite mechanical and electrical properties. The effects of radiation, including electron, gamma, and neutron exposures on composite properties were evaluated.
Applications of the resin systems include electrical insulation for cryogenic superconducting magnet systems, particularly those which will be subjected to irradiation. This high performance resin system will be of interest for cryogenic and high-temperature composite structural applications, which are fabricated by liquid impregnation methods such as Resin Transfer Molding. Other potential applications for these materials exist in areas such as automotive components and parts, aerospace equipment, industrial belts and hoses and other applications where high-temperature resistance and weatherability are required.