Drying wet fluoropolymer resin and exposing to oxygen source to reduce discoloration

Process for reducing thermally induced discoloration of fluoropolymer resin polymerized in the presence of hydrocarbon surfactant wherein all of the monovalent substituents on the carbon atoms of the hydrocarbon surfactant are hydrogen and wherein said fluoropolymer resin has an initial thermally induced discoloration value (Li) about 20 L units below the L value of equivalent fluoropolymer resin of commercial quality manufactured using ammonium perfluorooctanoate fluorosurfactant, said process comprising:

• polymerizing fluoromonomer in an aqueous dispersion medium in the presence of said hydrocarbon surfactant to form aqueous fluoropolymer dispersion having a raw dispersion particle size of 10 nm to 400 nm;
• isolating said fluoropolymer from said aqueous medium by separating wet fluoropolymer resin from the aqueous medium;
• drying said wet fluoropolymer resin to produce said fluoropolymer resin;
• and
• exposing said wet fluoropolymer resin to an oxygen source during drying, wherein said oxygen source is ozone containing gas.