JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
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2022
·
IF 6.364
Xudong Wang,Ke Chen,Ziqian Li,Haoming Ding,Yujie Song,Shiyu Du,Zhifang Chai,Hui Gu,Qing Huang
Herein, a series of chalcogen-containing MAX phases, Hf 2 (Se x S 1−x )C, were successfully synthesized, whose lattice parameter change follows the Vegard’s law. The average coefficient of thermal expansion (CTE) can be continuously tuned from 7.59 μK −1 to 9.93 μK −1 when the occupancy rate x of Se changes from 0 to 1. The substitution of Se for S effectively soften the crystal structures that is reflected by long average M-A bond in Se-alloying Hf 2 (Se x S 1−x )C. However, the CTEs along a and c axes in all Hf 2 (Se x S 1−x )C MAX phases are almost same which may be find application in thermal barrier coating (TBC) that isotropic volume change is highly demanding.
研究领域:
材料科学
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热物理学
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固体化学
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DOI
高影响因子
Materials Today Advances
·
2024
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IF 8.1
Heming Li,Panpeng Wei,Yongqi Wang,Qiushi Zhu,Xinming Wang,Weiguo Gao,Lin Tao,Ke Ma,Zhizhi Hu,Wei Chen
Polyimide (PI) faces new challenges in meeting the requirements of low coefficient of thermal expansion (CTE), low dielectric content/loss, and high thermal stability to be utilized effectively as a substrate for flexible electronic materials. At present research, the CTE of PI films can be reduced to around 5 ppm/K, with Tg > 420 °C. However, it is difficult to balance low CTE and high Tg at the same time, and reducing dielectric performance is even more difficult. This study focused on synthesizing four types of PI films (using BPDA as the dianhydride) by employing biphenyl structure diamines (PDA, BZD, DPT, DMP) with an increasing number of benzene rings. The improvement in CTE, dielectric properties, and thermal stability was observed with an increase in the number of benzene rings and a decrease in the number of imine rings in the PI horizontal structure. The Tetraphenylene PI-DMP exhibited values of ε and tanθ as 3.31 and 4.73 ‰ respectively under 10 GHz . Additionally, the biphenyl PI films demonstrated commendable thermal stability (Tg = 442°C ), outstanding mechanical properties (elastic modulus > 10 GPa ), and a low CTE ( 2 ppm/K within the temperature range of 50–300 °C, and close to the 3.6 ppm/K CTE of monocrystalline silicon). The low CTE, high thermal stability, and low dielectric properties that 5G flexible substrate materials need to be qualified are simultaneously reflected in this study. MS theoretical calculations were used to analyze the results. The excellent consistency with experimental results can promote the feasibility of MS theory in PI dielectric properties at high-frequency (10 Ghz). This innovative approach is anticipated to provide foldable chip fields with intrinsic biphenyl PI materials possessing low dielectric, low CTE, and high thermal stability.
研究领域:
材料科学
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电子工程
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DOI
高影响因子
MACROMOLECULAR MATERIALS AND ENGINEERING
·
2021
·Vol. 306
·期 3
·2000606
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IF 4.367
Pengfei Jiang,Jiulin Shen,Yao Wang,Jibin Zhang,Xiangfu Liu,Guoli Tu
Due to the development of dynamic flexible organic light-emitting diode displays, colorless polyimides (CPI) as the supporting or protecting optical films, are facing significant challenges due to the requirements of optical, mechanical, thermal, and chemical properties. Typical CPIs are derived from TFDB (2,2-bis(trifluoro-methyl)-4,4′-diaminobiphenyl)/6FDA (4,4′-(hexafluoroisopropylidene)diphthalic anhydride), which still need to be improved in both dimensional stability and optical performance. In this communication, a strong electron acceptor group, the sulfoxide bond, is first introduced into the TFDB block of CPI chains. Based on this introduction, the distribution of the electron cloud in the polymer chain is reconstructed under the strongly pulling electron effect, and the spatial conformation of the polymer chain is also affected by the rigid and twisted sulfoxide group. The influences on CPI's optical properties, especially the refractive index and the retardation, are studied and discussed in detail by experimental results and theoretical calculations. It is shown that the CPI with the sulfoxide group exhibits higher optical transparency, lower yellow index, phase retardation and coefficient of thermal expansion, which is an ideal material for CPI optical films.
研究领域:
材料科学
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光学工程
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高分子化学
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产品关联
DOI
高影响因子
EUROPEAN POLYMER JOURNAL
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2024
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IF 5.8
Xingwang Lai,Shan Huang,Jialin Zhang,Xialei Lv,Fangfang Niu,Jinhui Li
Photosensitive Solder resist (SR) materials require a high glass transition temperature ( T g > 170 °C) and a coefficient of thermal expansion matching that of copper (CTE≈17 ppm/°C) to meet the demands of manufacturing processes and application reliability. However, the commonly used epoxy resin in SR materials exhibits insufficient mechanical and thermal properties, failing to meet these requirements adequately. To address this issue, alkali-soluble photosensitive poly (amic ester) (PAE) materials were synthesized. By grafting a low-temperature curing accelerator, 6-([1,1′-biphenyl]–4-yl)–4-chloroquinoline (NQL), onto the hydroxyl groups of the PAE, the resultant grafted PAE resin was blended with an alkali-soluble photosensitive modified epoxy resin (APE) to enhance the mechanical and thermal properties of the SR composite. Research indicates that due to the low-temperature curing effect and electrostatic interactions of NQL, SR-2 (with a 10% PAE addition) exhibits a T g of 183 °C and a CTE of 16 ppm/°C, while SR-3 (with a 30% PAE addition) achieves a T g of 204 °C and a CTE of 20 ppm/°C. Furthermore, with the PAE addition of 5%, the lithography quality of SR is enhanced, enabling SR-1 to achieve a pattern resolution of up to 40 μm. The modification method involving PSPI blending has been shown to enhance the thermal stability, dimensional stability, and lithographic performance of SR, indicating significant potential applications in solder resist materials.
研究领域:
材料科学
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电子工程
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产品关联
DOI
高影响因子
JOURNAL OF POLYMER SCIENCE
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2025
·
IF 3.6
Zhenghui Yang,Haiquan Guo
Flexible polyimide (PI) films with outstanding dimensional stability, great heat resistance and excellent mechanical performance were crucial to the application and reliability of flexible displays. In this study, a series of amide-incorporating polyimides have been fabricated via the polycondensation of as-synthesized dianhydride monomers (AMDA, m-DAMDA, p-DAMDA, F-p-DAMDA) and 4,4′-diaminobenzanilide (DABA). The results revealed AMDA/DABA stood out for the sake of ultra-low coefficient of thermal expansion (CTE) at 2.6 ppm K −1 , high glass transition temperature ( T g ) at 415°C and great tensile strength of 326 MPa, elongation at break of 13% and tensile modulus of 6.9 GPa, which resulted from a highly linear molecular backbone linked by numerous hydrogen bonds arising from amide groups. In particular, AMDA/DABA exhibited superior mechanical performance to pyromellitic dianhydride/4,4′-diaminobenzanilide (PMDA/DABA: σ m = 261 MPa, ε b = 5.3%) and 4,4′-biphthalic anhydride/4,4′-diaminobenzanilide (BPDA/DABA: σ m = 174 MPa, ε b = 9.8%) previously reported. Hence, the AMDA/DABA film could be one of the promising candidates for application as polymer substrates for flexible displays. Graphical The CTE and T g values of as-synthesized PAI films; the formation of hydrogen bond between amide groups.
研究领域:
材料科学
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高分子化学
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柔性电子学
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DOI
高影响因子
ACS Applied Polymer Materials
·
2025
·
IF 4.7
Huifa Meng,Kaijin Chen,Chuying Li,Yanwei He,Zihao Huang,Haitao Huang,Zhenguo Chi,Siwei Liu,Yi Zhang
The use of traditional photosensitive polyimide (PSPI) insulating materials, which possess high coefficients of thermal expansion (CTE) and poor adhesion to copper, easily causes failure issues in the redistribution layers (RDLs). However, there are some trade-offs in the design of the low-CTE PSPI materials such as the ultraviolet (UV) transmittance of the precursors and the dielectric properties of the films. To overcome the above challenges, an AB2-type fluorinated monoamine (ETFPh-NH2) with a nonplanar steric structure was designed and synthesized, which was then used as an end-capper attached to poly(amic ester) (PAE) with a linear/stiff structure. The PSPI solutions were then developed by using the as-prepared PAE resins, solvents, and other additives. Despite the presence of ETFPh-NH2 with a relatively low molar ratio to the total precursor chains, the transparency of the PAE-4 was notably enhanced, resulting in the achievement of the high-resolution lithographic pattern. Meanwhile, the PI-4 film exhibited low-CTE characteristics (23.65 ppm K–1), and its mechanical and low dielectric properties were enhanced by the microbranched cross-link structure, which was constructed by the reaction of the arylethynyl groups during the imidization process. Furthermore, the adhesion between the PI films and Cu was significantly improved by introducing the aromatic silane (TMS). In short, PI-4, which exhibited high-dimensional stability, strong adhesion with Cu, and photopatternable capabilities, could be a feasible and reliable material for use in advanced packaging. In addition, the developed end-groups modification strategy seems to be an effective way to greatly improve the overall performance of PSPI materials.
研究领域:
材料科学
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微电子技术
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DOI
高影响因子
EUROPEAN POLYMER JOURNAL
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2023
·
IF 6
Gaojie Wu,Shengli Qi,Guofeng Tian,Dezhen Wu
In order to solve the challenge of balancing the thermoplastic processing properties and thermal dimensional stability of polyimide (PI) resin, in this research, 3,3′,4,4′-biphenyl tetracarboxylic diandhydride (BPDA) and 2,2′-bis(trifluoromethyl)benzidine (TFMB) were used as rigid components, 4,4′-oxydiphthalic anhydride (ODPA) and 4,4′-diaminodiphenyl sulfone (DDS) as flexible components. A series of random copolyimide resins was prepared by adjusting the molar ratio of rigid and flexible monomers. Determining the molar ratio which could balance the thermoplastic processing properties and thermal dimensional stability, block copolyimide resins with different rigid and flexible block lengths were then prepared in this ratio. The research showed that the molar ratio of monomers and the sequence structure of molecular chains had a strong influence on the performance of PI resins. When the content or block length of rigid component increased, the coefficient of thermal expansion (CTE) decreased but the glass transition temperatures ( T g ) and melt viscosity increased. The PI-B343 resin had a CTE value of 40.63 ppm/K and the lowest melt viscosity reached 675 Pa·s, achieved the simultaneous regulation of the thermoplastic processing properties and thermal dimensional stability for PI resin.
研究领域:
材料科学
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高分子化学
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产品关联
DOI
高影响因子
POLYMER BULLETIN
·
2026
·Vol. 83
·期 7
·368
·
IF 4.2
Yang Zhenghui,Guo Haiquan
The rapid development of cover sheets and backplanes in flexible active matrix organic light emitting diode (AMOLED) displays has intensified the demand for colorless polyimide (CPI) films with superior optical transparency, remarkable dimensional stability and great thermal resistance. In this study, three semi-alicyclic dianhydride monomers (HAMDA, HIMDA, TCDA) were successfully fabricated, followed by the separate polymerization with 2,2’-bis(trifluoromethyl)benzidine (TFDB) and trans-1,4-diaminocyclohexane (t-CHDA) to afford a series of colorless polyimide films. In terms of overall performance, TCDA/t-CHDA outperformed all other as-synthesized CPI films, featuring an excellent optical transmittance of 88% at 550 nm, a low haze value of 0.98 and a modest yellowness index at 2.95, alongside a reduced CTE of 17.7 ppm K − 1 and an elevated T g value of 334 ℃. Besides, TCDA/t-CHDA exhibited a robust tensile strength of 109 MPa and a remarkable elongation at break of 24%. The best overall performance of TCDA/t-CHDA was primarily attributed to the incorporation of the linear and rigid alicyclic structure as well as the formation of hydrogen bond originating from amide groups. The findings in this study provide valuable guidance for the design and fabrication of advanced colorless polyimide films targeting high-end applications.
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高影响因子
EUROPEAN POLYMER JOURNAL
·
2021
·
IF 4.598
Haoji Lao,Nafeesa Mushtaq,Guofei Chen,Bingyang Wang,Yuxia Ba,Xingzhong Fang
Two new series of transparent polyamide-imides (PAIs) with high modulus and low coefficient of thermal expansion (CTE) were prepared by random or block copolymerization of 4,4′-biphthalic dianhydride (BPDA) and p -phthaloyl chloride (TPC) with 2,2′-bis(trifluoromethyl)benzidine (TFDB). These series of PAIs displayed low CTE of 16–42 ppm/K, good mechanical properties with high tensile modulus ranging from 4.9 to 6.6 GPa, tensile strengths of 112–170 MPa and elongations at break of 2.0–5.4%, as well as high transparency with transmittances at 500 nm (T 500nm ) of 84–87%, which was greatly affected by the feed ratio of monomer BPDA & TPC, and the block length caused by block polymerization. The block copolymer PAI-3-B1 presented the best comprehensive performance with high transparency (T 500nm ) of 87%, low CTE of 16 ppm/K and high tensile modulus of 6.1 GPa.
研究领域:
材料科学
·
高分子化学
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2020
·
IF 10.652
Hongyan Cao,Bin Li,Xubao Jiang,Xiaoli Zhu,Xiang Zheng Kong
In contrast to conventional fluorescent polymers featured by large conjugation structures, a new class of fluorescent polymers without above conjugations are gaining constant interest owing to their significant academic importance and promising applications in diverse fields. These unconventional fluorescent polymers are in general composed of heteroatoms (e.g. N, O, P, and S) under different forms. Here we report our recent study on polyurea, prepared by a very simple one step precipitation polymerization of toluene diisocyanate in a binary solvent of water-acetone. This polyurea, basically consisting of phenyl ring and urea group, shows fluorescent emission in a broad concentration range, from very low (10 −5 mg/mL) to its solubility limit (50 mg/mL), and in a wide range of emission wavelength from UV to visible regions of up to 500 nm under varied excitation wavelength. The emission behaviors were fully studied under different concentrations and excitations. It was concluded that the emission in UV region was intrinsic due to the conjugation between the phenyl and the adjacent urea unit; while the emission in visible region, strongly excitation dependent, was caused by the cluster formation of the molecular chains, in accordance with the cluster-triggered-emission (CTE) mechanism. The formation of the cluster was tested through dynamic light scattering, FTIR and UV absorbance. Tested in presence of different metal ions, Fe 3+ demonstrated a quenching effect with high selectivity. Based on this study, different paper-based sensors were designed to detect Fe 3+ , H 2 O 2 in bioanalysis and for data encryption. This work provides a simple way to prepare a polyurea, a novel type of unconventional fluorescent polymer, with high emission performance distinct from its known analogues.
研究领域:
高分子化学
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材料科学
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分析化学
·
生物技术
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产品关联
DOI
PubMed
高影响因子
Materials Today Chemistry
·
2026
·
IF 7.4
Runze Liu,Zichun Ding,Jiazi Zhang,JianJian Jiao,Linyan Zhu,Xiaoxuan Liu,Yuming Lu,Jinyan Wang,Lishuai Zong,Jianhua Han,Xigao Jian
Leverage π–π stacking to design naphthalene-based bismaleimide resins. • Achieve high Tg and excellent thermal stability for electronic packaging. • Realize ultralow CTE combined with high modulus. • Deliver high mechanical strength in glass-fiber composites. With the rapid development of advanced electronic packaging technologies towards thinner, higher density integration, and long-term reliability, substrate materials for packaging are facing increasingly stringent requirements. Particularly, as device integration increases, the bonding between chips and packaging substrates becomes tighter, making the insufficient rigidity and mismatch in coefficient of thermal expansion (CTE) of the packaging substrates more pronounced. Consequently, developing substrate resin systems with both high rigidity and low CTE has become a focal point of current research. This paper starts from molecular structure design and successfully synthesizes a bis-maleimide resin rich in naphthalene rings (2,7-BMPN). The strong π-π stacking interactions between naphthalene rings significantly enhance the intermolecular forces within the cured resin network. Research results indicate that due to the tight molecular packing and enhanced rigidity brought by π-π stacking, the prepared BPMN resin blends exhibits excellent comprehensive performance: the glass transition temperature (T g ) of the pure resin reaches up to 335.4 °C, while the flexural modulus and strength of the fiberglass composite plate reach 40.5 GPa and 588.3 MPa respectively, significantly surpassing traditional bismaleimide systems. Moreover, the dense cross-linking structure effectively restrains segmental thermal motion, reducing the CTE to 6.7 ppm/K, showcasing exceptional dimensional stability. Additionally, this resin contributes significantly to lowering dielectric loss, achieving a minimum value of 0.00762 at 5 GHz. In summary, this high-performance BPMN resin constructed via the π-π stacking strategy demonstrates significant potential in the application of copper-clad laminate (CCL) core materials for advanced electronic packaging due to its outstanding mechanical strength, low thermal expansion characteristics, and overall superior performance. Download: Download high-res image (285KB) Download: Download full-size image
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高影响因子
EUROPEAN POLYMER JOURNAL
·
2022
·
IF 5.546
Ge Zhu,Haoji Lao,Feng Feng,Minyan Wang,Xingzhong Fang,Guofei Chen
Two series of poly(amide imide)s (PAIs) based on two novel isomeric amide-containing diamine monomers and different commercial aromatic dianhydrides were synthesized via thermal imidization. These PAIs exhibited excellent T g s ranging from 368 to 431 °C, low coefficients of thermal expansion (CTE) of 6.7–47.2 ppm/K, and good 5% weight loss temperatures ( T d5% s) in N 2 of 494–540 °C, which was attributed to the introduction of rigid backbone and strong intermolecular hydrogen bonding resulted from amide bond. In particular, PAI-1a and PAI-1b displayed well-balanced performance with T g s in the range of 419–431 °C, CTE in the range of 6.7–9.0 ppm/K, and mechanical properties with tensile strengths of 116–125 MPa, tensile moduli of 8.4–8.7 GPa, which could be probably used in flexible displays. In addition, the effects of two isomeric monomers on the properties of films were compared, and it was found that PAI-(1 – 3)a showed higher T g, T d5% and CTE, but lower tensile strength and transparency than PAI-(1 – 3)b .
研究领域:
高分子化学
·
材料科学
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）