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941.
Jihao Wang Yufen Han Zhiyang Xu Xiaozhen Yang Seeram Ramakrishna Yong Liu 《大分子材料与工程》2021,306(4):2000724
Polymer systems have typical multiscale characteristics, both in space and time. The mesoscopic properties of polymers are difficult to describe through traditional experimental approaches. Dissipative particle dynamics (DPD) is a simulation method used for solving mesoscale problems of complex fluids and soft matter. The mesoscopic properties of polymer systems, such as conformation, dynamics, and transport properties, have been studied extensively using DPD. This paper briefly summarizes the application of DPD to research involving microchannel flow, electrospinning, free-radical polymerization, polymer self-assembly processes, polymer electrolyte fuel cells, and biomedical materials. The main features and possible development avenues of DPD are described as well. 相似文献
942.
Shishan Xue Guanfei Liu Jingjuan Lai Peng An Yang Liu Yuanpeng Wu Yu Wang Zhiyong Ye Qiao Tang Hongwei Zhou 《大分子材料与工程》2021,306(11):2100415
Self-healing hydrogels often possess poor mechanical properties which largely limits their applications in many fields. In this work, boron nitride nanosheets are introduced into a network of the poly(vinyl alcohol)/borax (PVA/borax) hydrogels to enhance the mechanical properties of the hydrogel without compromising the self-healing abilities. The obtained hydrogels exhibit excellent mechanical properties with a tensile strength of 0.410 ± 0.007 MPa, an elongation at break of 1712%, a Young's Modulus of 0.860 ± 0.023 MPa, and a toughness of 3.860 ± 0.075 MJ m−3. In addition, the self-healing efficiency of the hydrogels is higher than 90% within 10 min at room temperature. Benefiting from the excellent self-healing properties, the shapeability of the hydrogel fragments is observed using different molds. In addition, the hydrogels display rapid pH-driven shape memory effects and can recover to their original shape within 260 s. Overall, this work provides a new approach to hydrogels with integrated excellent mechanical properties, self-healing abilities, and rapid pH-driven shape memory effects. 相似文献
943.
Zhiqiang Wu Qiang Guo Yang Liu Huihui Zhou Hua Zheng Xingfeng Lei Lei Gong Yanhui Chen Zhenguo Liu Qiuyu Zhang 《大分子材料与工程》2021,306(11):2100456
In order to meet the requirements of polymer dielectric materials for high thermal stability and excellent dielectric properties in the application of high-temperature film capacitors, a series of polyimide (PI) films are fabricated by introducing a self-synthesized aniline trimer (ACAT) with a conjugated structure in this work. Since the conjugated ACAT in the main chains of PI improves the electron polarization and carrier mobility of the PI molecular chains, the dielectric constant of the ACAT-PI films is greatly enhanced (4.4–7.4). Meanwhile, the dissipation factor does not increase apparently (0.002–0.013). The dielectric properties are stable even when the temperature is up to 200 °C, the thermal degradation temperature is as high as 450 °C, and the mechanical properties are also excellent (70–105 MPa). Among all the films, the PI film with 5 mol% ACAT exhibits the maximal energy density of 3.6 J cm−3 under the field of 426 kV mm−1, the high tensile strength (90 MPa) and the excellent thermal stability (Td5 = 515 °C). The work paves the way to prepare high-temperature polymer dielectric film materials with high energy storage density. 相似文献
944.
945.
Yang Zhu Xiangli Meng Qiang Zhang Liansheng Yan Hong Cui 《International Journal of Applied Ceramic Technology》2021,18(4):1330-1341
A 3D architecture carbon fiber preform, specifically fine-woven cloth and punctured felt preform, is used to manufacture a novel advanced Cf/C-SiC-ZrC composite. The composite matrix is produced by chemical vapor infiltration (CVI) plus precursor infiltration and pyrolysis (PIP) process and finalized by using a chemical vapor deposition (CVD) of SiC coating to make the final density of the material reach 1.95 g/cm3. The organic precursors of SiC and ZrC have a weight ratio of 4:1 in a xylene solute. The composite mechanical properties, such as tensile, compression, bending, shear, and Z-direction load bearing, are introduced under analysis to find possible applications for the composite. What is more, scanning electron microscope (SEM) images are employed to illustrate the failure behavior of the ceramic composite. The results showed that the punctured filament tows will be beneficial, not only for the composite to withstand compression force up to 308.6 MPa and shear strength to 18.14 MPa but also for the alternatively stacked weave piles and short fiber layers to support the punctured bundles, as well as to hold the composite structure under mechanical forces from different orientations, which is believed to reinforce the ceramic matrix for some high pressure and severe ablation applications. 相似文献
946.
Sajjad Muhammad Asif Sana Ullah Guan Linlin Jiao Yangjing Jiang Yuhan Zhang Linlin Wen Jia Zhang Shuyu Lin Yuting Zhang Shuangshuang Ding Zhiwei Ren Yang Zhou Xiaowei Hu Wanbiao Liu Zhu 《Journal of Inorganic and Organometallic Polymers and Materials》2021,31(11):4440-4441
Journal of Inorganic and Organometallic Polymers and Materials - The original version of this article unfortunately contained mistakes. In line 9 of the abstract, 5% should read as 2%. The... 相似文献
947.
以烧结刚玉、碳化硅等为主要原料,分别以红柱石0%、5%、10%、15%替换相同比例的烧结刚玉,同时外加少量的改性剂A制备四组浇注料,对比四种浇注料经1 400 ℃处理后的常温性能、线变化、抗热震性、抗碱侵蚀能力。结果表明,添加红柱石10%和改性剂1%的烧结刚玉基窑口浇注料表现出较好的使用性能。 相似文献
948.
949.
950.
Zhang Hongtao Cai Minghui Zhu Wanjun Sun Shenghui Yan Haile Yao Shengjie Luan Yikun Tang Shuai Hodgson P. D. 《Metallurgical and Materials Transactions A》2022,53(11):3869-3880
Metallurgical and Materials Transactions A - A cold-rolled low Al-added medium Mn steel was employed to investigate the low-temperature superplastic deformation at a relatively high initial strain... 相似文献