New colorless substrates based on polynorbornene‐chlorinated polyimide copolymers and their application for flexible displays

Abstract

Novel polynorbornene (PNB)-polyimide (PI) copolymers were synthesized based on poly(N-phenyl-exo-norbornene-5,6-dicarboximide) (PPhNI) and chlorinated PI (BPDA/ TCDB). Polynorbornene copolymers (PNCs) with diverse compositions of anhydride were synthesized via ring opening metathesis polymerization (ROMP) of N-phenyl-exo-norbornene-5,6-dicarboximide (PhNI) and exo-7-oxanorbornene-5,6-dicarboxylic anhydride(exo-NA), followed by copolymerization through a reaction with aromatic dianhydride (3,3 0 ,4,4 0 -biphenyltetra-carboxylic dianhydride, BPDA) and tetrachlorinated diamine (2,2 0 ,5,5 0 -tetrachlorobenzidine, TCDB). The copolymer (PNIC) films exhibited good optical transparency with a transmittance of around 70% at 400 nm and a good thermal stability with a glass transition temperature at 276-300 C. These flexible films also resisted most organic solvents and chemicals, such as methanol, acetone, tetrahydrofuran, N-methylpyrrolidone, ethyl acetate, hydrochloric acid, sodium hydroxide, and hydrogen peroxide, etc.Indium tin oxide (ITO) coated thin films were prepared at various substrate deposition temperatures with a radio frequency (r.f.) planar magnetron sputtering system. The ITO thin films that were deposited onto the PNIC copolymer substrates had good electrical and optical properties. An organic light-emitting device (OLED) was fabricated using the PNIC copolymer substrate with a structure of PNIC08/ ITO (anode)/hole-transporting layer (HTL)/ emitting & electron-transporting layer (EM&ETL)/aluminum (cathode). The flexible OLED fabricated on the ITO-grown PNIC substrate exhibited a performance that was comparable to corresponding ITO-grown glass substrates. Therefore, the ITO-grown PNIC substrate could possibly be a promising candidate as a substrate for flexible displays.

Interfacial adhesion behavior of polyimides on silica glass: A molecular dynamics study

“…In particular, PI is one of the most favorable substrate materials used in the production of flexible displays as they largely determine performance and reliability of the display. [5] [7], Although conventional plastic materials are shock-resistive, lightweight, chemically stable, easy to form in various shapes, suitable for continuous process, insulating, and optically transparent, their poor thermal stability has limited their use as flexible substrates for display applications. [8] [9], Specifically, during flexible display manufacturing, the processing temperature can rise above 300 C, over which most plastic materials decompose [9].…”

Investigation of interfacial charging and discharging in double-layer pentacene-based metal-insulator-metal device with polyterpenol blocking layer using electric field induced second harmonic generation

“…The significant commercial interest in organic electronics stems from their potential as building blocks for inexpensive and structurally flexible electronic devices, including radio frequency identification tags [2,3], smart cards [4], light emitting diodes [5,6], and flexible displays [7,8]. Organic field effect transistors (OFETs) have been demonstrated as a viable alternative to conventional devices for applications that require large area coverage, light weight, and low-temperature processing [9].…”

Transparent Polyimide Film with Improved Water and Oxygen Barrier Property by In‐Situ Exfoliating Graphite

“…[1][2][3][4] Aromatic polyimides (PIs) exhibit excellent mechanical and thermal properties that they are promising materials for substrates or interlayers in advanced semiconductors and microelectronics industries. [1][2][3][4] Aromatic polyimides (PIs) exhibit excellent mechanical and thermal properties that they are promising materials for substrates or interlayers in advanced semiconductors and microelectronics industries.…”