Synthesis of Polyimides Derived from 2,2-Bis[4-(4-aminobenzoyl)phenoxy]hexafluoropropane and Aromatic Dianhydrides

Aromatic diamines containing hexafluoroisopropylidene and ester moiety were synthesized from 4,4'-hexafluoroisopropylidene diphenol and nitrobenzoyl chloride. The reaction of aromatic diamines with hexafluoroisopropylidene phthalicdianhydride (6FDA) or pyromellitic dianhydride (PMDA) gave four kinds of poly(amic acid)s. Their inherent viscosities ranged from 0.196 to 0.346 dL/g. Poly(amic acid)s were converted to polyimides by thermal imidization. The glass transition temperatures (Tg) of polyimides were between 241 and 289 ℃. The 5% weight loss temperatures were recorded in the range of 430~492 ℃. The tensile strength of polyimide films were measured as 29.84~64.38 MPa.