Synthesis and Characteristics of Poly[N,N‘-diphenyl-N,N‘-bis(4-aminobiphenyl)-(1,1‘-biphenyl)-4,4‘-diamine pyromellitimide] as a Hole Injecting and Transporting Layer for Hybrid Organic Light-Emitting Device

Abstract

A novel hole injecting and transporting polymer, poly[N,N ‘-diphenyl-N,N ‘-bis(4-aminobiphenyl)-(1,1‘-biphenyl)-4,4‘-diamine pyromellitimide] (PMDA-DBABBD PI), was obtained by thermal imidization from its poly(amic acid) (PAA) made by the reaction of pyromellitic dianhydride with the DBABBD that was chemically reduced from N,N ‘-diphenyl-N,N ‘-bis(4-nitrobiphenyl)-(1,1‘-biphenyl)-4,4‘-diamine synthesized through the palladium-catalyzed amination. The materials were characterized by using 1H NMR, 13C NMR, FT-IR, HR GC-MS, EA, and DSC. The characteristics of the PAA or PI thin films were investigated with XPS and an impedance spectroscopy. The hybrid light-emitting devices (HOLEDs) with the PAA and PI thin films were fabricated to examine the performance of the polymeric thin films as a hole injecting and transporting layer. The PI thin film having the glass transition temperature of 200 °C showed stable characteristics in the application for the HOLED whereas the PAA thin film seemed to be unstable. The power efficiency of the HOLED with the PI thin film was 0.23 cd/A at 4000 cd/m2.

Synthesis and characterizations of a polyimide containing a triphenylamine derivative as an interlayer in polymer light-emitting diode

“…Aromatic polyimides have been widely used in the microelectronic devices and liquid crystal displays because of their excellent thermal, electrical, and mechanical properties. In several previous studies, several kinds of triphenylamine-containing polyimides were synthesized for the use of hole injecting and transporting layers for OLEDs [19][20][21]. These polyimides can be used as a polymer interlayer insoluble in common nonpolar organic solvent.…”

Microstructure and properties of fully aliphatic polyimide/mesoporous silica hybrid composites

“…From the characteristic transmission peaks, such as those at 3295 cm -1 for the amide stretching overlapped with the hydroxyl group transmission at 3200-3700 cm -1 , 1720 cm -1 for the C=O (acid) stretching, 1660 cm -1 for the C=O (amide) stretching, 1560 cm -1 for the NH (amide) stretching, and 1310-1277 cm -1 for the amide C-N bending, it was disclosed that the aliphatic polyamic acids were successfully synthesized by the reaction between the amines and BOCA. 17,18 The peaks of the PAA (s) samples were identical to those of PAA with the exception of a shift in the carboxylic acid peak position, due to the ionic interaction between the triethylamine moieties, thus proving the formation of the poly(amic acid) triethylamine salts, which was further confirmed using 1 H NMR spectroscopy. Figure 4 shows the 1 H NMR spectra of the synthesized polyamic acid PAA and water soluble poly(amic acid) triethylamine salts, PAA (s) .…”

Blue fluorescent conductive poly(9,10‐di(1‐naphthalenyl)‐2‐vinylanthracene) homopolymer and its highly soluble copolymers with styrene or 9‐vinylcarbazole

“…However, because of the inherent mechanical weaknesses of small‐molecule materials, the problematic recrystallization phenomenon under high thermal stress still persisted for the well‐designed 2‐methyl‐9,10‐di(2‐naphthyl)anthracene, and the requirements of the higher cost vacuum thin‐film deposition method also needed further improvement targeted at organic light‐emitting diode (OLED) applications . Recently, besides the ADN derivatives, several other kinds of anthracene derivatives with high glass transition temperature ( T g ) have also been reported .…”