ACS Sustainable Chemistry & Engineering
·
2018
·
IF 6.14
Zhihao Bi,Tuanwei Li,Hui Su,Yong Ni,Lifeng Yan
Epoxy resins are the main encapsulation materials for light-emitting diodes (LEDs) due to their high transparency, appropriate mechanical strength, and excellent thermal stability. However, environmentally benign materials needed to be developed with improving performances. Transparent wood and its nanocomposites prepared from natural biomass are potential alternative materials to them. Green preparation of transparent wood incorporating with trichromatic systems is an attractive topic, especially for white LEDs (W-LEDs). Here, multiple-color-emission carbon dots (CDs), serving as trichromatic systems in W-LEDs, were synthesized by tuning the extent of graphitization and surface function of the nanoparticles using citric acid and urea as feedstocks. Then, a green, facile, and energy-efficient method for the preparation of carbon dots/transparent wood (CDs-TW) composites was raised by the ultrafast removing of lignin from wood using deep eutectic solvent (DES, oxalic acid and choline chloride) under microwave-assisted treatment, and then, CDs and poly(acrylic acid) (PAA) were filled into the delignified wood through an in situ polymerization. The transparent wood film embedding multicolor CDs was fabricated, which showed white light emission under ultraviolet light excitation and enhanced mechanical tensile strength (60.92 MPa). Simultaneously, the as-prepared film can be used as an encapsulation film for white LEDs, which exhibited excellent color characteristics with the Commission Internationale Eclairage (CIE) color coordinates, a correlated color temperature (CCT), and a color rendering index (CRI) of (0.33, 0.32), 5237 K, and 83, respectively. This provides a simple route to prepare metal-free wood-based encapsulating materials for W-LEDs.
研究领域:
材料科学
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光学工程
·
环境科学
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产品关联
DOI
高影响因子
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
·
2018
·Vol. 102
·期 5
·2718-2726
·
IF 2.956
Hong Chen,Yao Wang,Jianhui Lin,Minmin Shuai,Haidi Zhu,Wengong Zhang,Qidan Ling
Herein, a novel transparent phenyl vinyl silicone resin nanocomposite containing exfoliated fluorescent Eu-containing hydrotalcite-like compound (EFHSN) is developed to serve as a dual role of color conversion and encapsulation material. Excited by near-NUV light, the EFHSN emits a strong characteristic red light (614 nm). Meanwhile, the EFHSN shows not only excellent transparency ( T > 95%) in the UV-Vis region and high refractive index (1.46) but also superior thermal stability, which could meet the need of commercial encapsulation materials and optical application. Therefore, the EFHSN is expected to be used in InGaN-based NUV light-emitting diodes and flexible optoelectronic device.
研究领域:
材料科学
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光学工程
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产品关联
DOI
高影响因子
POLYMER BULLETIN
·
2021
·Vol. 79
·期 9
·7177-7192
·
IF 2.87
Pan Zhaoqun,Chen Mianfeng,Zeng Keling,Kang Yingzi
In this paper, a cyclotetrasiloxane modified with epoxy resin was synthesized via hydrosilylation with 1, 3, 5, 7-tetramethylcyclotetrasiloxane (D4H) and 4-vinyl-1-cyclohexane 1, 2-epoxide (VCHO). The structure of tetramethylcyclotetrasiloxane modified with cyclohexane epoxide (D4H–VCHO) was characterized by Fourier transform infrared (FT-IR), 1H nuclear magnetic resonance (1H-NMR) and gel permeation chromatography (GPC). The effects of feeding methods, feeding ratios, catalyst dosages, reaction temperature and reaction time on the products were investigated. After 4-h reaction with 8 ppm catalyst at 90 °C, D4H–VCHO was obtained with an epoxy value of 0.521 and a refractive index of 1.4920. Then, with 4-methylhexahydrophthalic anhydride as a curing agent and tetrabutylammonium bromide as a catalyst, the obtained D4H–VCHO was cured at 90 °C for 1 h and then 120 °C for another hour. The cured products showed high light transmittance, strong thermal stability, suitable hardness and low water absorption. The glass transition temperature of cured materials was 151.6 °C, indicating the improvement of flexibility. In addition, the introduction of epoxy groups greatly enhanced the adhesion of silicone resins to substrates. The results demonstrated that the epoxy-modified silicone materials could be applied as LED packaging materials.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Materials Express
·
2016
·Vol. 6
·期 4
·371-376
·
IF 1.606
Chen Yu,Wang Yaxin,Ye Yanchun,Ma Lifang,Liu Yang
A novel electronic packaging material made of polyurethane-organic silicone copolymer was prepared by using hydroxyl terminated polybutadiene (HTPB) and α,ω-dihydroxy polydimethylsiloxane (PDMS) as soft segments, and isophorone diisocyanate (IPDI) as hard segments.
The correlation between the structure and properties of the electronic packaging material was studied with a series of samples prepared by different mass ratios of HTPB and PDMS. Several techniques, including FTIR, DSC, XRD, TG, and mechanical testing, were employed to characterize the structure
and properties, including micro-phase separation, thermal stability, and mechanical property of the products. It was found that the micro-phase separation between the soft segments and the hard segments was related to the mechanical properties, adhesive properties, and the thermal stability
of the copolymer. The preparation conditions were further investigated to obtain electronic packaging materials with ideal properties. The electronic packaging adhesive with optimum properties was achieved under the preparation condition of PDMS mass content of 5%–7%.
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
REACTIVE & FUNCTIONAL POLYMERS
·
2024
·
IF 4.5
Jiateng Huang,Feiyu Zhu,Wei Hu,Qiunan Xie,Xiaohan Li,Xiaoma Fei,Jingcheng Liu,Xiaojie Li,Wei Wei
Developing the packaging materials with superior high-temperature stability to meet the requirement of high-power devices is crucial. Herein, we synthesized 4-(4-aminophenoxy)phthalonitrile (APN) and blended it with polyfunctional epoxy resin (EP) to obtain the APN/EP (APNE) binary blends. Further, we employed the APNE as resin matrix to prepare a new high-temperature stable molding compound, aminophenoxyphthalonitrile epoxy molding compound (AEMC), aiming for high-power device packaging. Firstly, the curing behavior, reaction mechanism, thermal stability, and mechanical properties of the APNE system were systematically studied. Although the crosslinking density of the cured APNE decreased with increasing the APN content, the introduction of APN made the cured resins have the stable and rigid structures of isoindoline, triazine, and phthalocyanine. Thus, the cured APNE had the initial thermal decomposition temperature above 370 °C, the glass transition temperature ( T g ) up to 306 °C, and the char yield at 800 °C up to 61.1 %, showing an excellent thermal performance. In addition, the flexural strength, flexural modulus, and impact strength of the cured APNE also increased with increasing the APN content. Such good properties of the APNE resin matrix endowed the AEMC with an attractive performance. The AEMC exhibited a good compatibility in molding process with the current epoxy molding compound (EMC). The T g , thermal-aging resistance, intrinsic flame retardancy, dielectric properties, and thermal conductivity of the cured AEMC were all superior to those of the cured EMC. Therefore, the AEMC shows a good application prospect in the field of high-temperature electronic packaging.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2016
·
IF 2.567
Zhuo Chen,Zhuoyu Liu,Gebin Shen,Ruiheng Wen,Jie Lv,Jizhen Huo,Yingfeng Yu
Cycloaliphatic epoxy resin (3–4-epoxycyclohexane) methyl 3–4-epoxycyclohexyl-carboxylate (ECC) was formulated with flexible hydrogenated bisphenol A diglycidyl ether (HBADGE) to inspect the influence of chain flexibility on the performance and reliability of epoxy packaged Light-emitting Diode (LED). The properties of epoxy encapsulants were characterized by using differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), thermogravimetric analyses (TGA), ultraviolet visible (UV–vis) spectrophotometer, thermomechanical analyzer (TMA), scanning acoustic microscopy (SAM), and scanning electron microscopy (SEM). With the incorporation of flexible HBADGE, favorable properties were obtained, such as decreased thermal expansion coefficient (CTE), lowered storage modulus at reflow temperature, and depressed equilibrium water uptake for the epoxy packaging materials. The light transmittance of encapsulants differed after thermal and UV aging. Compared with Neat ECC and Neat HBADGE, the HBADGE-modified encapsulants endowed LED devices with good performance and high reliability.
研究领域:
材料科学
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光学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2015
·Vol. 132
·期 27
·
IF 1.768
Yan Zhang,Yin-wen Li,Jian Zheng,Hui-long Guo,Xiao-xiao Guan,Man-geng Lu,Kun Wu,Li-yan Liang
A novel thermal stability and highly transparent silicone resin-type material was prepared via hydrosilylation of vinyl-polyhedral oligomeric silsesquioxanes (POSS)-grafted methylhydrosilicone oil and vinylmethylsilicone oil in the presence of Karstedt catalyst. The morphology, mechanical property, thermal stability, optical transmittance, thermal-oxidation resistance of the vinyl-POSS-reinforced silicone resins were systematically investigated. Scanning electron microscopy showed that the vinyl-POSS-reinforced silicone resins had good compatibility with polydimethylsiloxane (PDMS) systems. The mechanical analysis and thermo gravimetric analysis indicated that the mechanical properties and thermal stability increased with increasing quantity of vinyl-POSS. However, the optical transmittance increased with the increasing amount of vinyl-POSS rather than decreased. In addition, the incorporation of vinyl-POSS did not improve the thermal resistance of the PDMS polymers. The product has the potential application for LED packaging. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132 , 42187.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
Small
·
2023
·
IF 13.3
Luyao Wang,Xin Li,Yongxin Qian,Wang Li,Tianshun Xiong,Yang Tao,You Li,Junwei Li,Yubo Luo,Qinghui Jiang,Junyou Yang
Due to the increased integration and miniaturization of electronic devices, traditional electronic packaging materials, such as epoxy resin (EP), cannot solve electromagnetic interference (EMI) in electronic devices. Thus, the development of multifunctional electronic packaging materials with superior electromagnetic wave absorption (EMA), high heat dissipation, and flame retardancy is critical for current demand. This study employs an in-situ growth method to load layered double hydroxides (LDH) onto transition metal carbides (MXene), synthesizing a novel composite material (MXene@LDH). MXene@LDH possesses a sandwich structure and exhibits excellent EMA performance, thermal conductivity, and flame retardancy. By adjusting the load of LDH, under the synergistic effect of multiple factors, such as dielectric and polarization losses, this work achieves an EMA material with a remarkable minimum reflection loss (RL) of −52.064 dB and a maximum effective absorption bandwidth (EAB) of 4.5 GHz. Furthermore, MXene@LDH emerges a bridging effect in EP, namely MXene@LDH/EP, leading to a 118.75% increase in thermal conductivity compared to EP. Simultaneously, MXene@LDH/EP contributes to the enhanced flame retardancy compared to EP, resulting in a 46.5% reduction in the total heat release (THR). In summary, this work provides a promising candidate advanced electronic packaging material for high-power density electronic packaging.
研究领域:
材料科学
·
电子工程
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产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF FOOD SCIENCE AND TECHNOLOGY
·
2024
·
IF 2.6
Hongye Li,Yi Yue,Yiming Jiang,Yi Wu,Mengqing Zhang,Xinan Zeng,Wei Zhao
Summary This study focuses on encapsulation of sugarcane polyphenols (SPs) to assess its impact on their bioaccessibility and efficacy in inhibiting starch digestion, thereby contributing to glycaemic control strategies. The hypothesis posits that encapsulation enhances both the bioaccessibility and functional effectiveness of SPs. Carboxymethyl cellulose (CMC) and carrageenan (CAR) were employed as encapsulating agents. The methodology included an evaluation of α-amylase inhibitory activity and the bioaccessibility of SPs across various encapsulation formulations in vitro digestion, highlighting a specific formulation that combines 0.5% CMC and 0.5% CAR to encapsulate 0.4% SPs. Findings reveal that this formulation significantly increases SPs' bioaccessibility and exhibits the highest α-amylase inhibitory activity, suggesting its potential to support a low glycaemic index (GI) diet (GI = 54.7). It was observed that the GI is significantly inversely correlated with the bioaccessibility of total polyphenols and proanthocyanidins in SPs, while the bioaccessibility of total flavonoids in SPs showed no significant effect on pGI. Interestingly, SPs encapsulated with CMC were less effective in inhibiting starch digestibility than unencapsulated SPs, attributed to the tight binding of CMC with polyphenols, which limits their interaction with starch and α-amylase. The study highlights the crucial influence of encapsulation materials on polyphenol functionality and emphasises the need for strategic encapsulation in modulating glycaemic responses. These findings advance the understanding of how processing technologies can optimise the health benefits of dietary bioactives, guiding future research towards functional applications and dietary interventions for glycaemic control.
研究领域:
食品科学
·
营养学
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2022
·
IF 4.326
Xiaohan Li,Yanglong Zhou,Ying Bao,Wei Wei,Xiaoma Fei,Xiaojie Li,Xiaoya Liu
Development of a new packaging material with superior high-temperature stability is becoming increasingly crucial in high-power and high-density electronics industry. In this study, we employed bis(3-ethyl-5-methyl-4-maleimidephenyl)methane (BMI), para-xylene phenolic resin (PF), and triphenylmethane novolac epoxy resin (EP) as matrix resins to develop high-temperature-stable BPE ternary resin molding compounds for power device packaging. BMI was first melt-blended with PF to obtain the premix with a reduced softening point for meeting the requirement of melt-kneading process. 2-Ethyl-4-methylimidazole with a dosage of 2 wt % of the ternary resins, could effectively promote the curing reaction, making the molding process of BPE molding compounds be compatible with that of the existing epoxy molding compounds (EMC). The introduction of BMI component could enhance the chain rigidity and heat resistance of cured resins. When the BMI content was more than 70 wt % of the ternary resins, the cured BPE molding compounds exhibited the glass transition temperature and initial decomposing temperature larger than 250 and 400 °C, respectively, indicating a much superior thermal performance to that of the cured EMC. Moreover, the flexural performance and the adhesion strength with copper at 260 °C, high-temperature aging resistance, dielectric properties, and thermal conductivity of the cured BPE molding compounds were also improved compared with those of the cured EMC. This study provides a promising strategy for preparing heat-resistant electronic packaging molding compounds.
研究领域:
材料科学
·
高分子化学
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2025
·
IF 6.3
Junqi Li,Feiyu Qin,Yiping Lv,Xin Yang,Tianhang Wu,Xiaoling Wang,Wenhui Xu,Nianjie Liu,Jun Wang,Lei Hu,Jun Sun,Xiangdong Ding
Thermal expansion mismatch among packing epoxy, silicon chip and copper microbump, generates severe thermal stress in 3D packaging and system in package . This inherent issue generally leads to warpage and interface crack of integrated circuit (IC). Furthermore, low thermal conductivity is equally disadvantageous to heat dissipation in electronic packing materials, especially for high power density IC. Consequently, the thermal expansion mismatch and low thermal conductivity concurrently result in the dilemma of IC and speed up structural failure. Conventionally, amorphous silica with the low thermal expansion is incorporated into the epoxy to design an epoxy molding compound in order to reduce the giant thermal expansion of epoxy. However, commercial epoxy/silica composites cannot effectively solve the critical issues of thermal expansion mismatch and low thermal conductivity. Here, the Cu 2 V 2 O 7 (CVO) with negative thermal expansion (NTE) was introduced into epoxy to design the unconventional Epoxy/CVO composites, which demonstrates suppressed thermal expansion and high thermal conductivity . When the mass fraction of CVO researches up to 60 %, the linear coefficient of thermal expansion of this composite decreases from 94.5 ppm·K ‐1 of epoxy down to a low value of 25.8 ppm·K ‐1 . Concurrently, this composite achieves a high thermal conductivity of 1.31 W·m ‐1 ·K ‐1 . Moreover, the resistivity, tensile strength , elastic modulus and thermal hardness are measured to be 9.3 × 10 10 Ω·m, 13.7 MPa, 7.4 MPa and 80.2 HD, respectively, close to the values of the ideal epoxy molding compound. This work develops an untraditional Epoxy/NTE composite and offers a systematic investigation of their thermal, mechanical and dielectric properties , which is highly helpful for the development of advanced electronic packaging materials.
研究领域:
材料科学
·
高分子化学
·
热力学
·
电子封装
·
功能复合材料
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2024
·
IF 6.3
Junwei Chen,Tao Luo,Houbin Huang,Liangzhu Zhang,Wei Chen,Guobing Qin,Jiajie Fan,Huidan Zeng
The high-temperature applications of Silicon Carbide (SiC) power devices are constrained by traditional epoxy molding compound (EMC). A significant challenge arises from the mismatch between the thermal expansion coefficients (CTE) of the encapsulant and the SiC chip, generating thermal and mechanical stresses during prolonged high-temperature operation. While glass encapsulants offer stability above 300 °C, these stresses can lead to mechanical degradation and eventual failure of SiC power devices. We design a glass-based encapsulation material to adjust the CTE of the glass to match that of the SiC chip (3–9 ppm/℃), enabling encapsulation of the device for long-term operation at 300 °C. Finite element analysis (FEA) confirms that the CTE adjustment effectively reducs internal thermal stresses. The glass composite with 10 wt% PbTiO 3 demonstrates a T g of 310 °C and a CTE of 8.48 ppm/℃, successfully encapsulating a SiC schottky barrier diode in TO-247 package form. The encapsulated device exhibits low leakage current, a reverse breakdown voltage of 1,700 V, and a thermal resistance of 0.45 °C/W. Notably, the device maintains excellent performance even after 1,176 h of high-temperature aging, including 336 h at 300 °C and exhibits minimal change during thermal cycling between −50 and 150 °C for 100 cycles. Long-term performance analysis demonstrates superior stability compared to EMC encapsulation. These results highlight the potential of glass-based encapsulants for wide band gap power devices, offering reliability and performance under extreme conditions.
研究领域:
材料科学
·
电力电子
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）