US Patent 11254764 Fluororpolymer compositions and coatings

A composition comprising at least one fluoropolymer and at least one solvent, wherein the solvent comprises a branched, partially fluorinated ether and wherein the partially fluorinated ether corresponds to the formula:CpF2p+1—O—CqH2q+1 wherein q is an integer from 1 to and 5 and p is an integer from 5 to 11; and wherein the fluoropolymer is a copolymer comprising at least 90% by weight (based on the total weight of the polymer, which is 100% by weight) of units derived from tetrafluoroethene (TFE) and one or more perfluorinated alkyl ethers selected from ethers corresponding to the general formulaRf—O—(CF2)n—CF═CF2 wherein n is 1 in which case the ether is an allyl ether, or 0 in which case the ether is a vinyl ether and Rf represents a perfluoroalkyl residue which may be interrupted once or more than once by an oxygen atom. Also provided are methods of preparing the compositions and methods for coating substrate with the compositions.