High-frequency 5G substrate: Low dielectric biphenyl polyimide with low CTE and high thermal stability

Materials Today Advances, Journal Year: 2024, Volume and Issue: 23, P. 100514 - 100514

Published: July 23, 2024

Polyimide (PI) faces new challenges in meeting the requirements of low coefficient thermal expansion (CTE), dielectric content/loss, and high stability to be utilized effectively as a substrate for flexible electronic materials. At present research, CTE PI films can reduced around 5 ppm/K, with Tg > 420 °C. However, it is difficult balance at same time, reducing performance even more difficult. This study focused on synthesizing four types (using BPDA dianhydride) by employing biphenyl structure diamines (PDA, BZD, DPT, DMP) an increasing number benzene rings. The improvement CTE, properties, was observed increase rings decrease imine horizontal structure. Tetraphenylene PI-DMP exhibited values ε tanθ 3.31 4.73 ‰ respectively under 10 GHz. Additionally, demonstrated commendable (Tg = 442°C), outstanding mechanical properties (elastic modulus GPa), (2 ppm/K within temperature range 50–300 °C, close 3.6 monocrystalline silicon). stability, that 5G materials need qualified are simultaneously reflected this study. MS theoretical calculations were used analyze results. excellent consistency experimental results promote feasibility theory high-frequency (10 Ghz). innovative approach anticipated provide foldable chip fields intrinsic possessing dielectric, stability.

Language: Английский

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Synthesis of High-Performance Colorless Polyimides with Asymmetric Diamine: Application in Flexible Electronic Devices

ACS Applied Materials & Interfaces, Journal Year: 2024, Volume and Issue: 16(36), P. 48005 - 48015

Published: Aug. 27, 2024

Colorless polyimides (CPIs) are widely used as high-performance materials in flexible electronic devices. From a molecular design standpoint, the industry continues to encounter challenges developing CPIs with desired attributes, including exceptional optical transparency, excellent thermal stability, and enhanced mechanical strength. This study presents validates method for controlling 2-substituents, specific emphasis on examining how these substituents affect thermal, mechanical, optical, dielectric characteristics of CPIs. The presence two CF

Language: Английский

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Thermally Stable and Transparent Polyimide Derived from Side‐Group‐Regulated Spirobifluorene Unit for Substrate Application

Macromolecular Rapid Communications, Journal Year: 2024, Volume and Issue: 45(17)

Published: July 16, 2024

Advancements in flexible electronic technology, especially the progress foldable displays and under-display cameras (UDC), have created an urgent demand for high-performance colorless polyimide (CPI). However, current CPIs lack sufficient heat resistance substrate applications. In this work, four kinds of rigid spirobifluorene diamines are designed, corresponding polyimides prepared by their condensation with 5,5'-(perfluoropropane-2,2-diyl) bis(isobenzofuran-1,3-dione) (6FDA) or 9,9-bis(3,4-dicarboxyphenyl) fluorene dianhydride (BPAF). The conjugated units endow higher glass transition temperature (T

Language: Английский

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Synergistic Enhancement of Mechanical and Dielectric Properties in Transparent Polyimides by Regulating Hydrogen Bonding and Microbranched Cross-Linking Structure

ACS Applied Polymer Materials, Journal Year: 2024, Volume and Issue: 6(17), P. 10738 - 10749

Published: Aug. 28, 2024

The development of polyimide (PI) films with excellent mechanical properties and low dielectric constants is crucial for flexible optoelectronic devices printed circuit boards. Here, a method to improve the decrease constant PI reported by introducing synergistic effect between hydrogen bonding (H-bonding) microbranched cross-linking structures. A triamine monomer (4,4′,4″-(1H-imidazole-2,4,5-triyl) trianiline, DTI) acting as bond donor was designed synthesized. It then in situ polymerized commercial 3,3′,4,4′-biphenyl tetracarboxylic dianhydride (BPDA), 4,4′-(hexafluoroisopropylidene) diphthalic anhydride (6FDA), 4,4′-oxidianiline (ODA), 1,4-phenylenediamine (PDA) obtain four different films, BPDA/ODA/DTI, BPDA/PDA/DTI, 6FDA/ODA/DTI, 6FDA/PDA/DTI. With introduction DTI, corresponding exhibited high modulus coefficient thermal expansion (CTE). When DTI content optimized, several high-performance suitable electronic applications were achieved. At 10 MHz, 6FDA/PDA series decreased from 3.39 2.89, while increased 3.41 4.60 GPa. CTE BPDA/PDA reduced 8.61 0.27, reduction approximately 97%. Structural characterization, density functional theory (DFT), molecular dynamics (MD) simulations revealed competitive relationships bonds branched cross-links within chains. This approach offers strategy overcome performance trade-off films.

Language: Английский

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High comprehensive properties of colorless transparent polyimide films derived from fluorine-containing and ether-containing dianhydride

RSC Advances, Journal Year: 2024, Volume and Issue: 14(44), P. 32613 - 32623

Published: Jan. 1, 2024

Fluorinated colorless transparent polyimide (CPI) films are crucial for flexible displays and wearable devices, but their development is limited by high costs relatively low mechanical properties.

Language: Английский

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Preparation and Properties of Fluorine‐Free and Organo‐Soluble Polyesterimides and the Films With Good Optical Transparency and Thermal Stability

Journal of Applied Polymer Science, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 26, 2025

ABSTRACT Fluorine‐free, fully aromatic polyimide (PI) films, characterized by the excellent optical transparency and high‐temperature endurance, have been successfully synthesized through either homopolymerization or copolymerization of an ester‐containing diamine, 2‐(4‐aminobenzoate)‐5‐aminobiphenyl (ABABP) two distinct dianhydrides: 2,2‐bis[4‐(3,4‐dicarboxyphenoxy)phenyl]propane dianhydride (BPADA) 9,9‐bis[4‐(3,4‐dicarboxyphenoxy)phenyl]fluorene (BPFPA). Owing to good solubility developed PI‐I PI‐V resins in polar aprotic solvents, particularly N,N‐dimethylacetamide (DMAc), N‐methyl‐2‐pyrrolidone (NMP) N,N‐dimethylformamide (DMF), synthesis process was performed a two‐stage chemical imidization technique. The polymer solutions DMAc were fabricated into films that showed exceptional clarity, featured with ultraviolet cutoff wavelength (λ) below 375 nm, light transmission at 450 nm (T ) surpassed 80%, b * values (CIE indices) 4.5, turbidity percentage (haze values) under 0.5%. Despite fact higher molar concentration BPFPA components segments led decline characteristics thermal resistance concurrently enhanced. resulting copolymerized PI exhibited glass transition temperature g over 264.9°C, along coefficients linear expansion (CTE) 56.7 ~ 65.9 ppm/K range 50 200°C.

Language: Английский

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In Situ Preparation of Siloxane-Linked Colorless Polyimides with Low Dielectric Constant

ACS Applied Polymer Materials, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 20, 2025

Language: Английский

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Colorless Transparent Polyimides with Balanced Dielectric and Optical Properties

Published: March 21, 2025

Language: Английский

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Synthesis and Characterization of High Glass Transition Temperature Colorless Polyimides Containing Hydrogen Bonding Carbazole Diamine for Optoelectronic Devices

ACS Applied Polymer Materials, Journal Year: 2025, Volume and Issue: unknown

Published: March 24, 2025

Maintaining ultrahigh heat resistance, a low thermal expansion coefficient (CTE), and adequate colorless transparency concurrently poses significant challenge for polyimides (CPIs), especially as substrate materials flexible optoelectronic devices. In this work, we designed synthesized hydrogen-bonding carbazole tetraphenyl aromatic diamine, 2,7-bis[2-trifluoromethyl-4-aminophenyl]-9H-carbazole (2,7-CPFDA). The corresponding polyimide (PI) films were via the copolymerization of 2,7-CPFDA 2,2′-bis(trifluoromethyl)benzidine (TFDB) with 3,3′,4,4′-biphenyltetracarboxylic dianhydride (BPDA) at varying molar ratios. All copolymer PI presented high resistance 5% weight loss temperatures (Td5) between 552 563 °C, glass transition (Tg) ranged from 354 to 380 °C. As content increased, CTE decreased 17.6 10.4 ppm K–1, while tensile modulus (E) rose 5.7 6.7 GPa, elongation break (ε) improved 5.4% 28%. When BPDA was substituted 9,10-diphenyl-9,10-bis(trifluoromethyl)-9,10-dihydroanthracene-2,3,6,7-tetraacid (6FDPDA) 4,4′-(hexafluoroisopropylidene)diphthalic anhydride (6FDA), CPI exhibited overall favorable properties. Notably, C–PI-7 Tg 456 excellent mechanical properties (E = ε 11.9%), (8.7 K–1), transmittance 450 nm (T450 86.1%), thereby meeting performance requirements electronic

Language: Английский

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Synthesis and properties of high heat-resistant transparent polyimides containing terphenyl skeleton

European Polymer Journal, Journal Year: 2025, Volume and Issue: unknown, P. 113924 - 113924

Published: March 1, 2025

Language: Английский

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