Fluorine-Containing Polyether Ketones Based on Fluorene Side Groups with Low Dielectric Constants and Excellent Thermal Performance

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

Published: Jan. 15, 2025

The rapid advancement of high-frequency communication networks has imposed more rigorous demands on the overall characteristics dielectric materials. Poly(aryl ether ketone)s (PAEKs) are good candidate materials for applications in microelectronic devices due to their excellent thermal stability, mechanical properties, and chemical stability. In this work, we endeavored incorporate large-volume fluorene structures into fluoro-PAEKs, employing strategies enhance polymer free volume reduce polarizations order decrease values Dk Df at high frequency. Therefore, a series poly(ether ketone) (PEK-pOCFBPF-X) copolymers were designed synthesized through nucleophilic polymerization using 4,4-difluorobenzophenone (DFK), phenolphthalein anilide-containing trifluoromethoxy groups (PPPBP-pOCF3), structurally ordered bisphenol (BPF) as monomers. results demonstrate that introduction BPF fluoro-PAEKs resin leads low constant (2.713–2.782@10 GHz) loss (0.00597–0.00825@10 GHz), well exceptional properties (Tg = 232–240 °C, Td5% 518–536 °C). Moreover, copolymer exhibits strength (tensile ≥ 81 MPa), minimal water absorption (≤0.0063), solubility. incorporation fluorenyl significantly enhances fraction (5.5%–5.8%), resulting lower density reduction constant. Simultaneously, by introducing C–F bonds with polarizability, polarizability is effectively diminished. These films, which exhibit superior stability constant, have great potential high-performance flexible electronic packaging field usage.

Language: Английский

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Development of Fluorinated Colorless Polyimides of Restricted Dihedral Rotation toward Flexible Substrates with Thermal Robustness

Macromolecules, Journal Year: 2024, Volume and Issue: 57(8), P. 3568 - 3579

Published: April 3, 2024

With the rapid expansion of product forms flexible displays and electronics, replacement brittle glass-based substrates with transparent polymer materials is strongly demanded. Colorless polyimides (CPIs) are reckoned as most promising substrate due to their inherent thermal stability, electrical insulation, high transparency, excellent foldability, proven roll-to-roll processing capability. However, CPIs prepared based on current common strategies have obvious weakness either transparency or/and thermal/mechanical all which cannot fulfill harsh requirements high-temperature device fabrication. Through great effort, we developed a series newly designed highly fluorinated aromatic diamines. The strong electron-withdrawing nature bond energy Ar–F Ar–CF3 enable level optical while retaining decomposition stability. This realized importantly restricted dihedral rotation effect in specific diamines, where multiple –F or –CF3 substitutions effectively restrict free torsion benzene rings create unique geometrical isomerism. brings advantages glass transition temperatures via increasing chain rigidity improved breaking electron conjugation along chain. Upon further copolymerization optimizations, an synergy ascension CPI films among robustness, mechanical strength, well low expansion, has been achieved, making them candidates for new electronics.

Language: Английский

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Fluorine atom substituted aromatic polyimides: Unlocking extraordinary dielectric performance and comprehensive advantages

Giant, Journal Year: 2024, Volume and Issue: 18, P. 100262 - 100262

Published: April 4, 2024

Low-dielectric polymers face prominent development challenges at high frequency. Particularly, the relationship between high-frequency dielectric loss and polymer structures remains not clear enough. Besides, strategies for achieving low usually have to scarify other important materials properties, e.g. heat resistance or dimensional stability. Herein, fluorine-containing aromatic polyimides were systematically investigated. Among them, simple fluorine atom (-F) substituted exhibit remarkable frequency (10 GHz) as well comprehensive advantages, including near-zero thermal expansion coefficient, extremely decomposition stability, optical transmittance excellent mechanical properties. The fundamental mechanisms of are fully discussed. Benefiting from unique electric effect compact size -F group, display dipolar density strongly restricted motion, contributing a reduced permanent polarization loss. Moreover, concept induced was introduced illustrate nontrivial impact F-substituted on conjugated electron cloud in system. This work only provides valuable insights understanding mechanism polymers, but also opens up broader application possibilities microelectronic wireless communications industries.

Language: Английский

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From Molecular Design to Practical Applications: Strategies for Enhancing the Optical and Thermal Performance of Polyimide Films

Polymers, Journal Year: 2024, Volume and Issue: 16(16), P. 2315 - 2315

Published: Aug. 16, 2024

Polyimide (PI) films are well recognized for their outstanding chemical resistance, radiation thermal properties, and mechanical strength, rendering them highly valuable in advanced fields such as aerospace, sophisticated electronic components, semiconductors. However, improving optical transparency while maintaining excellent properties remains a significant challenge. This review systematically checks over recent advancements enhancing the performance of PI films, focusing on various strategies through molecular design. These include optimizing main chain, side non-coplanar structures, endcap groups. Rigid flexible structural characteristics proper combination can contribute to balance stability transparency. Introducing fluorinated substituents bulky groups significantly reduces formation charge transfer complexes, both properties. Non-coplanar spiro cardo configurations, further improve stability. Future research trends nanoparticle doping, intrinsic microporous polymers, photosensitive polyimides, machine learning-assisted design, metal coating techniques, which expected enhance comprehensive expand applications displays, solar cells, high-performance devices. Overall, systematic design optimization have improved showing broad application prospects. aims provide researchers with references, stimulate more innovative applications, promote deep integration into modern technology industry.

Language: Английский

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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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Colorless transparent and thermally stable terphenyl polyimides with various small side groups for substrate application

European Polymer Journal, Journal Year: 2023, Volume and Issue: 202, P. 112640 - 112640

Published: Nov. 30, 2023

Language: Английский

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Synthesis of UV-resistant and colorless polyimide films for optoelectrical applications

npj Materials Degradation, Journal Year: 2024, Volume and Issue: 8(1)

Published: Jan. 11, 2024

Abstract Due to their excellent mechanical properties and intrinsic flexibility, polyimides (PIs) are promising candidates for optoelectrical applications under harsh conditions such as flexible organic solar cells well smart windows, etc. Much progress has been made on optical transmittance; however, there remain significant concerns about environmental stability, particularly UV resistance. Herein, 4 types of colorless (CPIs) with different molecular structures containing trifluoromethyl, ethers, or fluorenes carefully designed, the dependence resistance is explored systematically. It found that introduction isopropylidene, ethers effectively enhances CPI its initial performance (optical transparency, thermal toughness) simultaneously a result subtle manipulation conjugation structures. Specifically, optimized polyimide film shows decent ( $${T}_{550{\rm{nm}}}$$ T 550 nm ~ 88%, yellowness index ~3.26), stability $${T}_{5 \% }$$ 5 % 503 °C in N 2 atmosphere, $${T}_{{\rm{g}}}$$ g 312 °C). Moreover, after high-intensity irradiation, not only maintains over 90% but also retains 88%) 506 The design strategy paves way enhancing durability PIs energy conversion electronic resisting conditions.

Language: Английский

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Low dielectric constant and dielectric loss quinoxaline-based poly (aryl ether)s with excellent solubility, hydrophobic and thermal properties

European Polymer Journal, Journal Year: 2024, Volume and Issue: 215, P. 113156 - 113156

Published: May 21, 2024

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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