Properties of fluorinated polyimides

Abstract

This paper reports on two fluorinated polyimides synthesized using a fluorinated diamine, 2,2′bis(trifluoromethyl)-4,4′-diaminobiphenyl (TFDB). One polyimide, synthesized with TFDB and 2,2′-bis(3,4-dicarboxyphenyl) hexafluoropropane (6FDA), has a low dielectric constant, high optical transparency, and a low refractive index. The other, synthesized with TFDB and pyromellitic dianhydride (PMDA), has a low coefficient of thermal expansion (OTE). Because the two polyimides are synthesized using the same diamine, we can easily prepare a polymer blend of these two polyimides and synthesize their copolymer. The physical properties, such as the CTE, of the polymer blend or copolymer can be controlled by changing the 6FDA/TFDB polyimide or the 6FDA content, respectively. © 1992, The Society of Photopolymer Science and Technology(SPST). All rights reserved.