A TRITIUM PERMEATION RESISTANT POLYMER COATING

POLYMER MATERIALS AND COATINGS ARE USED IN TRITIUM SECONDARY AND TERTIARY CONFINEMENT GAS HANDING FACILITIES, IN GLOVE BOXES, WINDOW GASKETS, EPOXY PAINTS, AND PERSONAL PROTECTIVE CLOTHING ITEMS SUCH AS BUBBLESUITS, GLOVES, AND BOOTIES. THESE MATERIALS LACK HYDROGEN BARRIER PROPERTIES. THE FEW HYDROGEN BARRIER POLYMERS THAT EXIST ARE PRONE TO BETA AND GAMMA RADIATION DAMAGE AND LOSE THEIR BARRIER PROPERTIES IN HIGH HUMIDITY. HYDROGEN BARRIER POLYMERS TEND TO HAVE HYDROXYL (-OH) GROUPS IN THEIR STRUCTURE. THE EFFECT OF INCORPORATION OF -OH GROUPS ON THE BARRIER PROPERTIES OF PLASMA POLYMERS WILL BE INVESTIGATED. TYPICAL HIGHLY CROSSLINKED HYDROCARBON PLASMA POLYMERS ARE RADIATION RESISTANT, CAN BE MADE HYDROPHOBIC, AND CAN BE APPLIED AS TOUGH CONFORMAL COATINGS.THREE TYPES OF HYDROXYL-CONTAINING PLASMA POLYMERS WILL BE MADE, STARTING FROM THREE DIFFERENT PRECURSORS. PLASMA DEPOSITION PARAMETERS WILL BE VARIED TO YIELD THE HIGHEST NUMBER OF -OH BONDS IN EACH MATRIX, AND IR SPECTROSCOPY WILL BE USED TO DETERMINE THE BONDING AND RELATIVE ABUNDANCEOF -OH GROUPS IN EACH POLYMER COATING. PLASMA POLYMER COATINGS CONTAINING SIGNIFICANT NUMBERS OF -OH GROUPS WILL BE DEPOSITED INTO POLYSTYRENE MICROSHELLS AND TESTED FOR HYDROGEN PERMEABILITY USING ANALYTICAL TECHNIQUES DEVELOPED FOR THE CHARACTERIZATION OF INERTIAL FUSION TARGETS. THESE DATA WILL BE COMPARED WITH DATA PREVIOUSLY OBTAINED ON COMMON PLASMA POLYMER COATINGS CONTAINING ONLY C-H BONDING. IF THERE IS SIGNIFICANT IMPROVEMENT IN HYDROGEN GAS RETENTION, THE COATINGS WILL BE SUBJECTED TO TRITIUM EXPOSURE AND RETESTED FOR RADIATION DAMAGE EFFECTS.