| Examined by: | Vargot; Mathieu D. |
A method for casting a styrenic fluoropolymer film on a substrate includes preparing a polymer solution by dissolving the fluoropolymer in a solvent or solvent blend whose Hansen solubility parameters (HSPs. MPa.sup.1/2) satisfy the following relations: |SP.sub.b-SP.sub.p|<5, |SP.sub.b-SP.sub.s|<4, |SP.sub.b(H)-SP.sub.p(H)|<7, and 2<|SP.sub.b(H)-SP.sub.s(H)|<10 wherein SP.sub.b, SP.sub.p, SP.sub.s, are the total Hansen solubility parameters of solvent/solvent blend, fluoropolymer, and substrate, respectively; SP.sub.b(H), SP.sub.p(H), and, SP.sub.s(H) are the hydrogen-bond Hansen solubility parameters of solvent/solvent blend, fluoropolymer, and substrate, respectively; wherein the fluoropolymer comprises a moiety of: ##STR00001## wherein R.sup.1, R.sup.2, and R.sup.3 are each independently hydrogen atoms, alkyl groups, substituted alkyl groups, or halogens, wherein at least one of R.sup.1, R.sup.2, and R.sup.3 is a fluorine atom, and wherein R is each independently a substituent on the styrenic ring, n is an integer from 0 to 5 representing the number of the substituents on the styrenic ring. |
