CHEMICAL ENGINEERING JOURNAL
·
2020
·
IF 10.652
Yuewei Li,Shuqiang Peng,Jia-Tao Miao,Longhui Zheng,Jie Zhong,Lixin Wu,Zixiang Weng
With the development of 3D printing technology, photo-curable resin can be used to fabricate bulk objects. However, photo-curable epoxy resin used in 3D printers are commonly considered as a stiff material which is fragile. In this study, a molecular designed core-shell particles (CSP) comprising epoxide groups are prepared to improve the toughness and interlayer bonding of stereolithography resin (SLR). Results show that the tensile strength of SLR increases up to 57.2% with the addition of 5% w/w CSP, and the elongation at break increases up to 1303.6% with the addition of 7% w/w CSP. Moreover, the introduction of CSP reduces the anisotropy in tensile strength of fabricated workpieces from 42.1% to 0.3%. This novel SLR/CSP nanocomposite would expand the scope of application of 3D printing photo-curable resin to industrial workpieces with the requirements of stiff, toughness, mechanical isotropy and thermal resistance rather than being limited in the field of model design and prototyping.
研究领域:
材料科学
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增材制造
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产品关联
DOI
高影响因子
CHINESE JOURNAL OF POLYMER SCIENCE
·
2016
·Vol. 34
·期 3
·367-377
·
IF 1.811
Zhu Ai-di,Guo Ming-yu
In this work, we describe a straightforward approach to produce monodisperse Janus and core-shell particles by using organic solvent free single emulsion droplet-based microfluidic device combining with off-chip polymerization. To accomplish this, methyl methacrylate (MMA) was used as both the oil phase and solvent to dissolve a polymerizable PEGbased macromolecular surfactant, instead of traditional surfactant, and the photo-initiator. Janus particles can be easily obtained by off-chip UV polymerization due to polymerization induced phase separation between PEG and the formed poly(methyl methacrylate). At the same time, core-shell particles can also be easily attained by inverting the original collecting tube several times and then exposing to UV light. These results may extend the scope of microfluidic technology and the studies on polymerization induced self-assembly/phase-separation into easy fabrication of various new functional materials.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
Surfaces and Interfaces
·
2024
·
IF 5.7
Yuqing Xu,Beibei Cui,Xueqin Zhang,Ying Sun,Baoping Lin
The Cu@Ag core-shell particles are the highly anticipated functional materials in electronic applications which are required to be high electrical conductivity, good thermal properties and low cost. However, it remains a challenge to obtain a completely and uniformly coated Ag shell in low silver content. During the coating process, it is essential to regulate the reduction of Ag + on the surface of Cu to ensure uniformly silver shell. We developed a strategy to prepare uniformly coated Cu@Ag particles by employing hydroxy acids as complexing agents with “double-sided adhesive” function. Compared to conventional complexing agents, the employed hydroxy acids can not only coordinate with Ag + but also complex with Cu due to the more carboxyl and hydroxyl groups which act like a “double-sided adhesive”, that can pull Ag + to the surface of Cu, and then accomplish the coating of Ag with replacement and reduction reaction. The impact of different types of hydroxy acids as complexing agents on the coating effect of silver-clad copper powder was investigated when the silver addition was 15 %. Results indicated that the obtained Cu@Ag particles with tannic acid as complexing agent show high coating quality layer with low surface sliver content (11.4 %). Moreover, the obtained Cu@Ag particles exhibit good dispersibility, promising thermal stability and low electrical resistivity (30 μΩ·cm).
研究领域:
材料科学
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电子应用
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产品关联
DOI
高影响因子
LANGMUIR
·
2012
·
IF 4.186
Xiaohui Meng,Yinyan Guan,Zhengdong Zhang,Dong Qiu
Core–shell particles with cross-linked core and shell were used as seed particles to produce composite Janus particles. It was found that when the shell has distinctly higher cross-linking degree than the core, Janus particles with very unusual structures can be obtained. These particles have two parts, with one part embraced partially or entirely by the other part, adjustable by parameters such as phase ratio or cross-linking degree. On the basis of experimental observations, a possible mechanism for the formation of such unusual Janus particles has been proposed. Janus particles with arms are used to emulsify water–toluene mixtures, forming oil-in-water (O/W) emulsions at very high internal phase content with rather low concentration of particles. Nonspherical emulsion droplets were observed, indicating that these Janus particles are likely to jam at the interface, forming a strong protecting layer to stabilize emulsions.
研究领域:
材料科学
·
界面化学
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产品关联
DOI
PubMed
高影响因子
Journal of Materials Chemistry C
·
2020
·Vol. 8
·期 48
·17403-17409
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IF 7.059
Cuifang Meng,Dandan Yang,Ye Wu,Xuejia Zhang,Haibo Zeng,Xiaoming Li
Encapsulating cesium lead halide (CsPbX3, X = Cl, Br, and I) perovskite quantum dots (PQDs) into stable shells has been proved to be an effective strategy for improving their stability, which however usually forms agglomerated particles or alters PQDs’ original morphology and optical properties. Herein, we propose a surface activation strategy to prepare single CsPbBr3@SiO2 core–shell particles. (3-Aminopropyl)triethoxysilane (APTES) is used as a bifunctional surface ligand, which not only effectively passivates the surface defects of PQDs, but also provides –SiOCH3 and –SiOH groups for the formation of Si–O–Si covalent bonds with the subsequently introduced silanes. Furthermore, by controlling the hydrolysis rate of silanes, we realized the preparation of single CsPbBr3@SiO2 core–shell particles with an average shell thickness from 1 to 2.7 nm, and the PQDs maintained their initial cubic morphology and optical properties after coating. The stability of CsPbBr3@SiO2 in harsh environments has been effectively improved owing to the complete encapsulation of the SiO2 shell. As a result, the emission peak of CsPbBr3@SiO2 remains constant at 515 nm after being heated at 60 °C for 84 h, and the photoluminescence (PL) intensity still remains 90% after storage for 6 h in a high humidity environment. This work not only enhances the stability of PQDs for practical applications but also provides a reliable method to synthesize single core–shell particles, which can be instructive to other PQD systems.
研究领域:
材料科学
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纳米技术
·
化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2015
·Vol. 3
·期 7
·3988-3994
·
IF 7.443
Xiang Li,Fangyuan Gai,Buyuan Guan,Ye Zhang,Yunling Liu,Qisheng Huo
Fe@C core–shell particles were successfully synthesized by coating Fe2O3 particles with resorcinol–formaldehyde resins (RFs) and then calcining to make the RFs carbonize, and at the same time to reduce the core to Fe. Furthermore, we designed and synthesized Fe@C yolk–shell particles to increase the number of active sites on the Fe surface. Compared with pure Fe material, the Fe in these particles possesses a high surface area without serious aggregation. Tests to remove 4-chlorophenol suggest that both these kinds of particles can degrade chlorophenol rapidly and thoroughly based on a Fenton-like reaction. Using Fe@C yolk–shell particles, the chlorophenol can be degraded to a concentration below the HPLC detection limit (<0.5 mg l−1) within 12 minutes. The magnetic properties and good stability of Fe@C endow it with promising potential for water treatment.
研究领域:
材料科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
Materials
·
2018
·Vol. 11
·期 12
·2482
·
IF 2.467
Jiaxing Sun,Xiao Zhang,Long Bai,Zhiguo Li,Zhao Jia,Jiyou Gu
A novel strategy for fabricating inverted core-shell structured latex particles was implemented to investigate the morphology and properties of polyvinyl acetate (PVAc)-based latex. In this study, active grafting points were synthesized onto the surface of PVAc latex cores via grafting acrylonitrile (AN) to obtain a controllable coating growth of the shell monomer, styrene (St). The effect of shell growth on the morphological evolvement was explored by tuning the time of shell monomer polymerization. Unique particle morphologies, transferring from “hawthorn” type, over “peeled pomegranate” type, to final “strawberry-like” type, were observed and verified by electron microscopy. The morphological structure of latex particles exerted a significant effect on the particle size, phase structure, and mechanical properties of the obtained emulsions. The water-resistance of PVAc-based latex was also evaluated by the water absorption of latex films. More importantly, the experimental results provided a reasonable support for the controlled growth of St monomer, that is, the self-nucleation of dispersive St monomer can be transformed to in-situ coating growth on the PVAc core surface depending on the AN-active grafting points. This fabricating approach provides a reference for dynamical design and control of the latex particle morphology.Keywords:inverted core-shell particle;polyvinyl acetate;acrylonitrile grafting;shell growth;morphological evolution
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED SURFACE SCIENCE
·
2022
·
IF 7.392
Mo Zou,Jingzhi Chen,Zhaoyang Wei,Weiwei Lei,Jun You,Jie Liu,Qunchao Zhang,Dean Shi
Core-shell particles with rigid core and soft rubber shell have been proven to be effective in strengthening and toughening polymers simultaneously when the rubber shell thickness is controlled within a critical range. However, the critical value of the so-called thickness-to-diameter ratio τ (the ratio of the rubber shell thickness to the rigid core diameter) obtained in the previous work are all from polymer blends containing core–shell particles with monodispersed particle size. Does the critical τ value still exist in the core–shell toughening system with polydisperse particle sizes? Is it possible to produce core–shell particles with polydisperse particle sizes but the same τ value? In this paper, the post-emulsification method is first reported to prepare core–shell particles with polydisperse SiO 2 particles as the rigid core and ethylene–vinyl acetate copolymer grafted maleic anhydride (EVA- g -MAH) as the rubber shell, in which the thickness of the rubber shell can be well controlled and tuned via varying the feeding weight ratio of SiO 2 and EVA- g -MAH. The τ value is only determined by the weight ratio of SiO 2 and rubber, and has nothing to do with the SiO 2 particle size. A series of polyamide 6 (PA6)/SiO 2 @EVA core–shell toughening systems are prepared via melt blending process. It is proved the existence of the critical τ value ( τ cbd ) above which brittle-ductile transition happens in the core–shell toughening system with polydisperse core–shell particle sizes. The value of τ cbd is 0.069 in PA6/SiO 2 @EVA core–shell toughening system.
研究领域:
材料科学
·
聚合物工程
✓ 已验证
DOI
高影响因子
RSC Advances
·
2014
·Vol. 5
·期 9
·6489-6493
·
IF 3.708
Xuanxuan Qiao,Yuxia Luo,Aihua Sun,Chongyang Wang,Jianfei Zhang,Chengyi Chu,Jianjun Guo,Gaojie Xu
Surface modified colloidal SiO2@TiO2 core–shell particles were chosen to study their responsive photonic properties and the effect of surface on structural colour under low electric field. The surface of SiO2@TiO2 core–shell particles was controllably coated by PDDA, PVA and SiO2. A corresponding colloidal suspension of the modified SiO2@TiO2 showed completely different reflection spectra. The dielectric spectrum was employed to explain the effect of surface properties on the assembly.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry C
·
2021
·Vol. 10
·期 1
·265-273
·
IF 7.393
Xu Liu,Xiao-Rong Sun,Chen Luo,Hong-Zhi Ma,Hua Yu,Yan Shao,Ming-Bo Yang,Bo Yin
The development of self-powered technology in nano-energy puts forward higher requirements for triboelectric nanogenerators (TENGs), in which it is necessary to further improve their output performance to broaden their scope of application, and environmentally friendly and sustainable development needs to be realized as well by the recycling of friction materials. The preparation of environmentally friendly and sustainable TENGs is reported in this work through a feasible and cost-effective solution casting method, in which polyethylene oxide (PEO) and Ecoflex were utilized as positive/negative friction materials, respectively. With introducing micron-sized core–shell Ag@SiO2 particles into the PEO matrix, micro–nano structures were constructed to increase the effective contact area, while the enhancement of dielectric properties was also achieved in the meantime. The Ag@SiO2–PEO/Ecoflex TENG with optimum particle content of 50 wt% produced a short-circuit current of 10 μA, an open-circuit voltage of 95 V, and a transfer charges of 35 nC at a frequency of 3 Hz. The maximum output power density of Ag@SiO2–PEO-50 wt%/Ecoflex TENG up to 1.5 W m−2 was reached under different load resistances. The stability and flexibility of TENGs were verified as well, which led to a novel approach for their application in wearable-flexible electronic devices. Additionally, the sustainable utilization of TENGs was achieved as a result of the water solubility of the PEO material, with significant output performance retention. This work provides an innovative approach for the further modification of the output performance of flexible and sustainable TENGs.
研究领域:
材料科学
·
能源技术
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2025
·
IF 6.9
Mingyao Li,Xiaoming Wang,Ling Weng,Xue Li,Xiaorui Zhang,Houyu Wang,Li Kong
In recent years, with the breakthroughs in nanomaterial technology and manufacturing processes, the energy density of energy storage devices has been significantly improved, laying the foundation for their large-scale commercial applications. Flexible dielectric energy storage materials have received extensive attention due to their advantages such as low processing difficulty, light weight, efficient charge–discharge processes, and excellent energy storage density. However, in polymer-based nanocomposites, there are problems such as poor dispersion of nanoscale fillers and the formation of physical defects, which in turn affect the mechanical properties. To address the above issues, in this study, through surface modification technology, insulating polydopamine (PDA) was coated on the surface of barium titanate (BaTiO 3 , BT) nanoparticles to synthesize functional BT core–shell particles, which were then doped into a polyarylether nitrile (PEN) matrix with good dielectric properties to prepare PEN/BT@PDA composite dielectric materials. The influence of surface-modified BT core–shell particles on the microstructure and energy storage performance of PEN-based composite dielectric materials was investigated. The results show that the BT@PDA particles are uniformly dispersed and have good compatibility within the PEN matrix. At the same time, the dielectric properties and breakdown performance of PEN/BT@PDA have also been improved. Under an electric field of 100 Hz, the maximum dielectric constant of the PEN/BT@PDA composite dielectric material is 6.8, which is a 74 % increase compared to the original PEN film, and the dielectric loss is 0.052, showing frequency dependence. The BT@PDA particles can capture the free electrons that are free in the PEN system under an electric field, reducing the carrier mobility, thus suppressing the formation of conductive paths inside the material, regulating the overall electric field distribution of the system, and improving the insulation performance of the composite film. Therefore, the breakdown strength of the PEN/BT@PDA composite dielectric material is increased, with the maximum breakdown strength being 180.9 kV/mm, which is a 14 % increase compared to the pure PEN film. Through calculation, the maximum energy storage density of the PEN/BT@PDA composite dielectric material is 0.78 J/cm 3 , which is an 81.4 % increase compared to the pure PEN. Under an external electric field of 120 kV/mm, the charge–discharge efficiency of the PEN/BT@PDA composite dielectric material can reach 69 %, demonstrating that BT@PDA can enhance the energy storage performance of PEN[30].
研究领域:
材料科学
·
纳米技术
·
电气工程
·
高分子科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Science-Advanced Materials and Devices
·
2023
·
IF 8
Xiaoming Wang,Ling Weng,Yumeng Zhang,Ruize Shen,Xiaorui Zhang,Lizhu Guan,Xue Li,Sheng Ye
Herein, a method is proposed for preparing MnO 2 @carbon core–shell particles and MnO 2 @carbon/polyvinylidene fluoride (PVDF) composite films. The effect of MnO 2 @carbon core–shell particles on the dielectric properties of polymer composites was investigated. Furthermore, a comprehensive dielectric property test was conducted on the composite films. The results reveal that with the addition of MnO 2 @carbon core–shell particles, the dielectric properties of the composite films also improved. The dielectric constant of the 10 wt% MnO 2 @carbon composite is 24.2 at 100 Hz, which is 3 times that of PVDF (7.68). Currently, the energy storage density of the composite film is 4.95 J cm −3 at ∼2300 kV cm −1 . The addition of MnO 2 @carbon core–shell particles effectively improves the energy storage density of PVDF. Based on this result, the influence of the carbon shell on the dielectric properties of the composite thin films is analysed and discussed. The significant improvement in dielectric properties is mainly due to the increased interfacial polarisation induced by the carbon shell. These characteristics of PVDF/MnO 2 @carbon composites indicate that the proposed method is a practical pathway to developing high-performance composites.
研究领域:
材料科学
·
电气工程
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）