Fuel-resistant articles having low temperature flexibility from halogenated polydimethylsiloxanes

Claim 1

THE METHOD OF PREPARING AN ELASTIC MEMBER RESISTANT TO SWELLING IN AROMATIC FUELS WHICH INCLUDES THE STEPS OF DISSOLVING A POLYDIMETHYLSILOXANE ELASTOMERIC GUM HAVING A MOLECULAR WEIGHT OF AT LEAST 400,000 IN FROM TEN TO TWENTY PARTS OF A VOLATILE HALOGENATED SOLVENT TO FORM A LOW VISCOSITY SOLUTION, MAINTAINING THE SOLUTION AT A TEMPERATURE BETWEEN 100* F. AND 180* F., ADDING SMALL AMOUNTS OF AN ORGANIC PERIOXIDE TO THE SOLUTION, PASSING A MIXTURE OF CHLORINE AND SEVERAL TIMES AS MUCH INERT GAS INTO SAID SOLUTION AT SUCH A RATE THAT SOME CHLORINE LEAVES THE SOLUTION UNREACHED, AND FOR SUCH A PERIOD OF TIME THAT THE MOLES OF CHLORINE PASSED INTO THE SOLUTION CONSTITUTE 110-210% OF THE SILOXY MONOMER UNITS OF THE SILOXANE, REMOVING THE HYDROGEN CHLORIDE AS RAPIDLY AS FORMED, RECOVERING THE PARTIALLY CHLORINATED POLYDIMETHYLSILOXANE GUM HAVING A CHLORINE TO SILICON RATIO GREATER THAN ONE BUT LESS THAN TWO, MIXING THE PARTIALLY CHLORINATED SILICONE GUM WITH A FILLER SELECTED FROM THE CLASS CONSISTING OF SILICON DIOXIDE, TITANIUM DIOXIDE, MAGNESIUM OXIDE, ALUMINUM OXIDE AND ZINC OXIDE, AND ADDITIONAL ORGANIC PEROXIDE CURING AGENT, MOLDING AND THEN BAKING THE MIXTURE TO FORM SAID ELASTIC MEMBER FROM PARTIALLY CHLORINATED SILICONE RUBBER.

Claim 2

THE METHOD OF PREPARING AN ELASTIC MEMBER RESISTANT TO SWELLING IN AROMATIC FUELS WHICH INCLUDES THE STEPS OF DISSOLVING A POLYDIMETHYLSILOXANE ELASTOMERIC GUM HAVING A MOLECULAR WEIGHT OF AT LEAST 400,000 IN FROM TEN TO TWENTY PARTS OF A VOLATILE HALOGENATED SOLVENT TO FORM A LOW VISCOSITY SOLUTION, MAINTAINING THE SOLUTION AT A TEMPERATURE BETWEEN 100* F. AND 180* F., ADDING SMALL AMOUNTS OF AN ORGANIC PERIOXIDE TO THE SOLUTION, PASSING A MIXTURE OF CHLORINE AND SEVERAL TIMES AS MUCH INERT GAS INTO SAID SOLUTION AT SUCH A RATE THAT SOME CHLORINE LEAVES THE SOLUTION UNREACHED, AND FOR SUCH A PERIOD OF TIME THAT THE MOLES OF CHLORINE PASSED INTO THE SOLUTION CONSTITUTE 110-210% OF THE SILOXY MONOMER UNITS OF THE SILOXANE, REMOVING THE HYDROGEN CHLORIDE AS RAPIDLY AS FORMED, RECOVERING THE PARTIALLY CHLORINATED POLYDIMETHYLSILOXANE GUM HAVING A CHLORINE TO SILICON RATIO GREATER THAN ONE BUT LESS THAN TWO, MIXING THE PARTIALLY CHLORINATED SILICONE GUM WITH A FILLER SELECTED FROM THE CLASS CONSISTING OF SILICON DIOXIDE, TITANIUM DIOXIDE, MAGNESIUM OXIDE, ALUMINUM OXIDE AND ZINC OXIDE, AND ADDITIONAL ORGANIC PEROXIDE CURING AGENT, MOLDING AND THEN BAKING THE MIXTURE TO FORM SAID ELASTIC MEMBER FROM PARTIALLY CHLORINATED SILICONE RUBBER.