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乳液共聚合 1

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硅阳极 1

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Graft copolymerization of -isopropylacrylamide with 3-(methacryloxy)propyl trimethoxysilane on ultrafine

ZHANG Liping, ZHU Yi, NI Caihua

《化学科学与工程前沿（英文）》 2008年第2卷第3期页码 242-247 doi: 10.1007/s11705-008-0043-y

摘要： Thermosensitive core-shell particles were synthesized through graft copolymerization of -isopropylacrylamide with [ 3-(methacryloxy) propyl]trimethoxysilane (MPT) coupled on the surface of ultrafine silica beads. The copolymerization was carried out using polyvinyl alcohol as a surfactant, water and cyclohexanol as mixed solvent, and 2,2′-azobis(isobutyronitrile) as an initiator. The effect of surfactant concentration and the composition of the mixed solvent on the graft rate were investigated. The structure of modified silica was confirmed by infrared spectra. Differential scanning calorimetry (DSC) has revealed the thermosensitivity of the particles. The thermosensitive particles were used as packing materials of high performance liquid chromatography (HPLC) columns for separating naphthalene derivatives. Satisfactory separation was obtained by controlling the temperature of the column. In contrast, the packing material of silica-MPT has no such separation efficiency due to the lack of thermosensitivity. The effect of the composition of the mobile phase on the separating efficiency was also investigated. The temperature-controlled separation was effective only when the water content was higher than 90% (v/v) in the water-methanol mobile phase. The mechanism for the temperature-controlled separation is attributed to a polarity change of poly(-isopropylacrylamide) which undergoes volume phase transition on the silica surface as the temperature increases.

关键词： undergoes water-methanol surfactant concentration copolymerization chromatography

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Copolymerization of polyketones catalyzed by polyacrylonitrile resin-supported palladium acetate

GUO Jintang, ZHANG Hongxin, WANG Bo, YE Yaqin

《化学科学与工程前沿（英文）》 2008年第2卷第2期页码 165-170 doi: 10.1007/s11705-008-0010-7

摘要： The crosslinked polyacrylonitrile (PAN) was synthesized by suspension polymerization using acrylonitrile (ANT) and divinylbenzene (DVB). Effects of a variety of conditions on the polymerization of PAN particle size and stiffness were investigated. Polyketone was prepared by the copolymerization of carbon monoxide (CO) and styrene (ST) catalyzed by PAN resin-supported palladium acetate. The resin-supported catalyst and the copolymerization product were characterized by infrared spectroscopy (IR) and Scanning Electron Microscopy (SEM). Effects of the components of a catalytic system and reaction time on the catalytic activity were studied. The reusability of the resin-supported catalyst was also investigated. Results indicated that the resin-supported catalyst has excellent catalytic property. The yield of polyketone was 6.2348 g when using 1 g of resin and 22.4 mg of palladium acetate.

关键词： copolymerization Electron Microscopy monoxide excellent catalytic Polyketone

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Cryo-copolymerization preparation of dextran-hyaluronate based supermacroporous cryogel scaffolds for

Dongjiao ZHOU, Shaochuan SHEN, Junxian YUN, Kejian YAO, Dong-Qiang LIN

《化学科学与工程前沿（英文）》 2012年第6卷第3期页码 339-347 doi: 10.1007/s11705-012-1209-1

摘要： Dextran-hyaluronate (Dex-HA) based supermacroporous cryogel scaffolds for soft tissue engineering were prepared by free radical cryo-copolymerization of aqueous solutions containing the dextran methacrylate (Dex-MA) and hyaluronate methacrylate (HA-MA) at various macromonomer concentrations under the freezing condition. It was observed that the suitable total concentration of macromonomers for the preparation of Dex-HA cryogel scaffold with satisfied properties was 5% (w/w) at the HA-MA concentration of 1% (w/v), which was then used to produce the test scaffold. The obtained cryogel scaffold with 5% (w/w) macromonomer solution had high water permeability (5.1 × 10 m ) and high porosity (92.4%). The pore diameter examined by scanning electron microscopy (SEM) was in a broad range of 50–135 μm with the mean pore diameter of 91 μm. Furthermore, the cryogel scaffold also had good elastic nature with the elastic modulus of 17.47±1.44 kPa. The culture of 3T3-L1 preadipocyte within the scaffold was investigated and observed by SEM. Cells clustered on the pore walls and grew inside the scaffold indicating the Dex-HA cryogel scaffold could be a promising porous biomaterial for applications in tissue engineering.

关键词： cryogel scaffold tissue engineering dextran hyaluronate 3T3-L1 preadipocyte

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茂金属催化剂催化烯烃聚合反应的研究 ——聚合物的聚集行为和热性能 Letter

吴长江, Minqiao Ren, Liping Hou, Shuzhang Qu, Xinwei Li, Cui Zheng, Jian Chen, 王伟

《工程（英文）》 2023年第30卷第11期页码 93-99 doi: 10.1016/j.eng.2023.07.001

摘要：

Olefin solution polymerization can be used to obtain high-performance polyolefin materials that cannot be obtained via other polymerization processes. Polyolefin elastomers (POE) are a typical example. Due to cost, only a few linear α-olefins (e.g., 1-butene, 1-hexene, and 1-octene) are used as comonomers in solution polymerization in industry. However, α-olefin comonomers with other structures may have different effects on polymerization in comparison with common linear ones. Moreover, the properties of the corresponding materials may differ significantly. In this work, copolymers of ethylene with linear and end-cyclized α-olefins are synthesized using a metallocene catalyst. The copolymerization of ethylene with linear α-olefins results in a higher turn-over frequency (TOF) and lower incorporation than copolymerization with end-cyclized α-olefins, which may indicate that end-cyclized α-olefins have a higher coordination probability and lower insertion rate. In this reaction, the comonomer is distributed randomly in the polymer chain and efficiently destroys crystallization. End-cyclized α-olefins exhibit a much stronger crystallization destructive capacity (CDC) in the copolymer than linear α-olefins, possibly because linear α-olefins act mainly in the radial direction of the main chain of the polymer, while end-cyclized α-olefins act mainly in the axial direction of the main chain.

关键词： Metallocene catalyst Ethylene copolymerization Comonomer distribution Crystallization destructive capacity

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Copolymerization of 1-butene and 1-hexene with supported titanium catalyst

ZHAO Yongxian, SHAO Huafeng, WANG Bo, YAO Wei, HUANG Baochen

《化学科学与工程前沿（英文）》 2007年第1卷第3期页码 304-309 doi: 10.1007/s11705-007-0056-y

摘要： With TiCl/MgCl (Ti) and Al(-Bu) (Al) as catalysts, the thermoplastic copolymer of 1-butene(Bt) and 1-hexene(He) was synthesized successfully. The effects of Bt/He, Ti/(He+Bt), Al/Ti, temperature and reaction time on conversion, catalyst efficiency(CE), intrinsic viscosity([η]) and insoluble content were studied. The copolymer was analyzed with Fourier transform-infrared (FTIR) and nuclear magnetic resonance (H-NMR). Results showed that the optimal polymerization conditions were: He/Bt = 0.25, temperature 40ºC–50ºC, Al/Ti = 400–500, Ti/(Bt+He) = 3×10-4*times;10, time 4 h. Intrinsic viscosity was found to increase with increasing Ti/(Bt+He) and decreasing Al/Ti and polymerization temperature. When the molar content of He, Al/Ti and polymerization temperature increased, the insoluble content in CHCl of copolymers decreased. When Ti/(Bt+He) and reaction time increased, the insoluble content in CHCl of copolymers also increased. The crystallization and stereoregularity of poly(1-butene) decreased with the addition of He.

关键词： reaction conversion temperature polymerization temperature magnetic resonance

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实现“不可行”的共聚反应以构筑氮掺杂多孔碳的理想聚合物前驱体 Article

亓士超, 陆筱杰, 楼寅聪, 周睿, 薛丁铭, 刘晓勤, 孙林兵

《工程（英文）》 2022年第16卷第9期页码 154-161 doi: 10.1016/j.eng.2021.07.031

摘要：

某些预想的概念验证反应虽可能产生具有新功能或新应用潜力的材料，但最终常被证明是不可实现的或从商业角度上是不可行的。为了在溶剂环境中探索未知反应的反应条件，科研人员已付出了大量的努力，也浪费了大量的精力。因为人们普遍相信通过将反应物溶解在溶剂中，可以提高反应物的活性，从而促进反应。本研究发现了一个反常现象：在不同溶剂环境下，1,3,5-三（氯甲基）-2,4,6-三甲基苯与三聚氰胺的共聚反应都是无法实现的，然而利用无溶剂法却可成功地实现该反应。通过第一性原理计算和分子动力学模拟，证明了溶剂反应不具备的两个决定性因素，即由副产物的及时释放所推动的反应平衡和活化单体分子在固相中的受限热运动却可基于无溶剂法实现。由于具有较高的芳香性和氮杂环含量，由无溶剂法得到的共聚物表现出良好的应用潜力，可作为制备氮掺杂多孔碳的前驱体，使氮掺杂多孔碳具有令人满意的碳产率、理想的残氮含量、理想的结构特性，与最近报道的其他代表性同类吸附剂相比，在二氧化碳捕获能力方面展现出竞争潜力。

关键词：无溶剂法溶剂效应共聚反应氮掺杂多孔碳

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用于锂离子电池的富醚/酯/氟黏结剂配方 Article

Xianqing Zeng, Donglin Han, Zeheng Li, Hongxun Wang, Gu Wu, Yong Deng, Kai Liu, Li Xie, Chengdu Liang, Min Ling, Yuchuan Huang

《工程（英文）》 2022年第19卷第12期页码 199-206 doi: 10.1016/j.eng.2022.05.020

摘要：

由于硅阳极体积膨胀过大，无法在高能量密度电池中实现实际应用。研究人员一直专注于在阳极中添加黏结剂以限制体积膨胀，来解决这一问题，因为黏结剂的氢键和机械性能可以用来增强黏附力和适应硅阳极的体积变化。在这里，我们综合考虑了黏结剂的氢键、力学性能、稳定性以及与电解液的相容性，设计了一种富醚/酯/氟的复合聚合物P(TFEMA-co-IBVE)。该黏结剂配方具有优异的稳定性、黏结性和机械强度，能够适应硅电极体积的剧烈变化，表现出优异的电化学性能，面积容量高达5.4 mA∙h∙cm⁻²。这种新型聚合物设计可应用于下一代锂离子电池的其他电极材料。

关键词：硅阳极乳液共聚合氟原子醚酯