Synthesis and Characterization of Polyimides from Bis(3-aminophenyl)-4-(1- adamantyl) Phenoxy Phenyl-phosphine Oxide (mDAATPPO)

摘要

As microelectronic devices became smaller and lighter during the past decades, low dielectric constant became one of the critical factors in minimizing electrical power loss and delay in signal transmission in microelectronic applications [1-2]. Among the attempts to improve dielectric, incorporation of adamantyl moiety has received great attention [3-6] since it is known to impart high Tg, excellent thermal stability, and good dielectric properties owing to highly symmetrical molecule consisting of three cyclohexane rings, forming “cage-molecule” [7]. Recently as low as 2.54 of dielectric constant was reported with polyimide containing diamantane, but adhesion property was not investigated. In this study, therefore, it was attempted to prepare a novel diamine monomer, bis(3-aminophenyl)-4-(1-adamantyl)phenoxyphenyl phosphine oxide (mDAATPPO), containing adamantane and phosphine oxide moieties. This monomer was used to prepare polyimides with 6FDA, BTDA, ODPA and PMDA via a conventional two-step synthesis; preparation of poly(amic acid), followed by solution imidization. The molecular weights of polyimides were controlled to 20,000 g/mol by off-stoichiometry and polyimides were characterized by FT-IR, NMR, GPC, TGA and DSC. In addition, solubility, intrinsic viscosity and dielectric constant measurements were also evaluated.