NEW PERFLUOROETHER FLUIDS EXHIBITING EXCELLENT OXIDATIVE AND THERMAL STABILITIES

GENERAL PROCEDURES FOR PREPARING LOW MOLECULAR WEIGHT PERFLUOROALKYL ETHERS HAVE BEEN DEVELOPED. THE FLUORINATED PRODUCTS, SERVING AS MODEL COMPOUNDS FOR HIGHER MOLECULAR WEIGHT POLYMERS, WILL BE USED TO DETERMINE STABILITY PARAMETERS FOR HIGHER MOLECULAR WEIGHT POLYMERS. SIMPLE MOLECULES, TYPICALLY DIMETHYLETHER DERIVATIVES FOR THE BASIC REPEATING UNIT OF THE POLYMER OF INTEREST, WILL BE SYNTHESIZED USING A VARIETY OF TECHNIQUES. ONE PROCEDURE CONSISTS OF FIRST SYNTHESIZING THE HYDROCARBON ANALOGUE OF THE DESIRED PERFLUORO COMPOUND, FOLLOWED BY REPLACEMENT OF THE HYDROGEN WITH FLUORINE USING A CONTROLLED REACTION WITH ELEMENTAL FLUORINE. THIS PROCEDURE ALLOWS ONE TO PREPARE FLUOROCARBON DERIVATIVES OF ESSENTIALLY ANY HYDROCARBON POLYMER OR MOLECULE. A SECOND BUT VERY IMPORTANT GENERAL PROCEDURE INVOLVES FLUORINATION OF ESTERS, FOLLOWED BY CONVERSION OF THE LINEAR PERFLUOROESTER TO A PERFLUOROETHER USING SF4. THIS TECHNOLOGY IS ESPECIALLY WELL SUITED FOR PREPARING HIGHLY BRANCHED PERFLUOROETHERS AND PERFLUOROPOLYETHERS AS WELL AS ETHERS CONTAINING MORE THAN TWO SEQUENTIAL CARBONS IN THE CENTRAL CHAIN OF THE ETHER/POLYETHER. THERMAL STABILITY STUDIES PERFORMED ON THE MODEL COMPOUNDS SHOULD DETERMINE THE USEFUL TEMPERATURE RANGE FOR THE POLYMERS AS WELL AS PROVIDE MECHANISTIC INFORMATION CONCERNING THE WAY THE VARIOUS POLYMERS OF INTEREST MAY DECOMPOSE.