INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2020
·
IF 3.573
Shikai Hu,Tao Shou,Mingming Guo,Runguo Wang,Jun Wang,Hongchi Tian,Xuan Qin,Xiuying Zhao,Liqun Zhang
Thermoplastic polyurethanes (TPUs) have received considerable attention because of their flexible structure and comprehensive performance. 3,3-Dimethyl-4,4′-diphenyl diisocyanate (TODI) was first introduced to fabricate high-performance TPU by tailoring the mole ratio of the hard segment to the soft segment and the molecular weight of the soft segment for three-dimensional (3D) printing. The influence of the microstructure on glass transition temperature, tensile strength, modulus, loss factor, and softening temperature was investigated. The annealing process was proved to increase the degree of microphase separation of TODI-based TPU. Compared with TPU derived from widely commercialized isocyanates, our prepared TODI-based TPU exhibited remarkably high heat resistance. In addition, it is worth noting that our TODI-based TPU prepolymer has long-term and stable storage, which is beneficial for industrial application. This work is crucial to fabricate new TPU elastomer materials with high heat resistance for 3D printing and evaluate the structure–property behavior of TODI-based TPU, which could help other researchers design TODI-based TPU.
研究领域:
高分子材料科学
·
材料化学
·
生物医用材料
·
增材制造
·
热力学性能
·
功能高分子
·
结构-性能关系
✓ 已验证
DOI
高影响因子
Reaction Kinetics Mechanisms and Catalysis
·
2024
·Vol. 137
·期 3
·1535-1552
·
IF 1.7
Feng Shangzhen,Zhou Hantao,Jiang Huanjin,Yang Jie,Chen Jixiang
Herein, the Ni–Co alloy supported on TiO 2 catalysts were prepared by sol–gel method assisted with Polymethyl Methacrylate (PMMA) template, and they were tested for in situ aqueous phase hydrodeoxygenation (HDO) of methyl palmitate to hydrocarbons using methanol as hydrogen donor. It has been found that the introduction of PMMA decreases the Ni–Co alloy particles size, reduces the metal-support interactions (SMSI), constructs the mesopores and enlarges the mesopore size. Also, the Ni–Co alloy particles can be partially embedded in TiO 2 , beneficial to the catalyst stability since the sintering and leaching of the Ni–Co alloy particles can be suppressed under hydrothermal condition. In the in situ HDO of methyl palmitate, the main deoxygenation pathway is decarboxylation/decarbonylation on the Ni–Co alloy catalysts. The catalysts prepared with PMMA exhibits higher activity than that without PMMA, giving the pentadecane yield of 86.2% at 310 °C. This is ascribed to their more exposed active sites and wider mesopores. Moreover, the catalyst is not obviously deactivated during five reactions.
研究领域:
催化
·
化学工程
·
材料科学
·
环境科学
·
有机化学
✓ 已验证
DOI
高影响因子
JOURNAL OF SOLUTION CHEMISTRY
·
2023
·Vol. 53
·期 2
·257-277
·
IF 1.2
Gao Xiang,Hong Biyuan,Zhang Meiyu,Li Dan
Carbonate esters are used as additives in biodiesel to improve its thermophysical properties for better applicability. In this work, the experimental densities, dynamic viscosities and refractive indices for binary mixtures of dimethyl carbonate and four fatty acid esters (methyl decanoate, ethyl decanoate, methyl laurate, ethyl laurate) have been measured and presented over the complete concentration range at temperatures range from 293.15 to 323.15 K under normal pressure. The excess molar volumes and the viscosity deviations of the four binary mixtures were calculated with the measured data and correlated with the Redlich-Kister equation. The excess Gibbs energy of activation was also calculated. From the values of excess properties of the binary mixtures and its deviations indicate that the changes of molecular interactions in the mixtures. The experimental results could be useful for the study of biodiesel-carbonate blended fuels.
研究领域:
化学工程
·
燃料科学
·
热力学
·
物理化学
·
可再生能源
✓ 已验证
DOI
高影响因子
Journal of Macromolecular Science Part A-Pure and Applied Chemistry
·
2018
·
IF 1.057
Daidong Wei,Bing Liao,Qiwen Yong,Tao Li,Huiyi Wang,Jianheng Huang,Hao Pang
Castor oil (CO) based hyperbranched urethane acrylates (HBUAs), namely C10-IH and C20-IH, were synthesized by modifying the hydroxyl groups of first (C10)- and second (C20)-generation of CO-based hyperbranched polyesters with isocyanate-bearing semi-adducts (IPDI-HEA). Herein, the C10 and C20 polyesters were prepared using the renewable CO as a B3 core molecule and dimethylolpropionic acid as an AB2 monomer via a pseudo-one-pot condensation procedure. For comparison, a CO-based urethane acrylate (CO-IH) was synthesized by directly modifying the hydroxyl groups of CO with IPDI-HEA. The structure-property relationship of the UV-cured films was investigated in detail. Consequently, the number of terminal urethane acrylates greatly influenced their final properties. The tensile strength of the C20-IH based UV-cured sample could be improved by 129% in comparison with the CO-IH based sample, and its pencil hardness reached up to 7H. Furthermore, the chemical resistance tests and the morphology study proved that the C20-IH based UV-cured coatings exhibited excellent chemical stability and superb microstructure. These improvements can be attributed to the unique oligomer architecture that combined the structural features of hyperbranching, castor oil chains and multiple urethane acrylates.
研究领域:
材料科学
·
高分子化学
·
涂料技术
·
化学工程
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2024
·
IF 8.3
Chengzhou Tao,Tianle Zheng,Pengfei Jia,Wuze Gong,Guma Yila,Lina Wang,Tianxi Liu
Hindered by the high diffusion energy barrier of Li+ in graphite anode layers, the low-temperature application of traditional Li-ion batteries is limited. Lithium metal without intercalation and with excellent specific capacity is expected to support battery operation at low temperatures. However, due to the low conductivity, high freezing point, and strong solvation energy of traditional carbonate electrolytes, the application of lithium–metal batteries at low temperatures remains challenged. In this paper, an all-ester-based ternary solvent electrolyte based on fluorinated carbonate and methyl acetate is developed to improve the cyclic efficiency of the Li-metal anode at subzero temperatures. Methyl acetate, with low viscosity and low freezing point, endows Li+ with efficient transfer in the bulk phase at low temperatures. Fluorinated cosolvent regulates the solvation structure, thereby facilitating Li+ desolvation while forming a LiF-rich solid electrolyte interphase. The electrolyte exhibits good compatibility with the Li-metal anode, as confirmed by the significantly reduced kinetic barrier of Li+ diffusion at the interface. The theoretical calculations suggest that anions occupy the dominant positions within the inner solvation sheath. The in situ/ex situ characterizations provide straightforward evidence of a dendrite-free Li-metal electrode during cycling. As a result, the symmetric Li||Li cell is able to cycle stably for thousands of hours at current densities of 0.5 mA cm–2 and 1 mAh cm–2. When paired with a LiFePO4 cathode, the battery at 0.2 C (1 C = 170 mA g–1) has a capacity retention of 95.4% after 200 cycles at −15 °C and 92.6% after 100 cycles at −20 °C, respectively.
研究领域:
材料科学
·
电化学
·
能源存储
✓ 已验证
DOI
高影响因子
iScience
·
2023
·Vol. 26
·期 9
·107608-107608
·
IF 5.8
Yujing Li,Huihui Luo,Shuo Wang,Lei Li,Guosong Li,Wen Dai
An unprecedented efficient protocol is developed for the oxidative cleavage of C≡C bonds in alkynes to produce structure-diverse esters using heterogeneous cobalt nanoparticles as catalyst with molecular oxygen as the oxidant. A diverse set of mono- and multisubstituted aromatic and aliphatic alkynes can be effectively cleaved and converted into the corresponding esters. Characterization analysis and control experiments indicate high surface area and pore volume, as well as nanostructured nitrogen-doped graphene-layer coated cobalt nanoparticles are possibly responsible for excellent catalytic activity. Mechanistic studies reveal that ketones derived from alkynes under oxidative conditions are formed as intermediates, which subsequently are converted to esters through a tandem sequential process. The catalyst can be recycled up to five times without significant loss of activity.
研究领域:
化学
·
材料科学
·
催化
·
有机合成
✓ 已验证
DOI
PubMed
高影响因子
ANALYST
·
2020
·Vol. 145
·期 15
·5206-5212
·
IF 3.978
Tianzi Li,Yetong Gao,Huiya Li,Chenyang Zhang,Yifei Xing,Meng Jiao,Yu-e Shi,Wei Li,Yongqing Zhai,Zhenguang Wang
Butyrylcholinesterase (BChE) activity is an important index for a variety of diseases. In this work, a “turn-on” assay is proposed based on controlling the inner filter effect (IFE) of MnO2 nanosheets (NSs) on sulfur nanodots (S-dots). The fluorescence of S-dots is effectively quenched by the MnO2 NSs, due to the wide overlap of the emission spectrum of S-dots and absorption spectrum of MnO2 NSs, together with the superior light absorption capability of MnO2 NSs. BChE can catalyze acetylthiocholine and produce thiocholine, which effectively decomposes the MnO2 NSs into Mn2+, resulting in the disappearance of the IFE and recovery of fluorescence of S-dots. Two-stage linear relationships between the ratio of fluorescence intensity and concentration of BChE are observed from 0.05 to 10 and from 10 to 500 U L−1. A limit of detection of 0.035 U L−1 is achieved, which is the best performance so far. The as-proposed assay is robust enough for practical detection in human serum, and it can avoid interference from its sister enzyme (acetylcholinesterase) and glutathione at the micromolar level. The presented results provide a clue for the functionalization of S-dots, and offer a powerful tool as an analytic technique for nanomedicine and environmental science.
研究领域:
分析化学
·
纳米技术
·
生物医学工程
·
环境科学
✓ 已验证
DOI
高影响因子
OPTICS AND LASER TECHNOLOGY
·
2025
·
IF 5
Yani Chen,Haiyu Qiao,Ning Jiang,Yayun Liu,Fanshuo Jia,Chuanyang Wang
High-quality plastic joining techniques using welding are urgently required in many engineering areas. Controlling morphology formation in joints plays an important role in the final quality, but relatively controlling methods are still challenging. In this paper, we propose an in-situ formed mechanical riveting structure between polycarbonate (PC) and polybutylene terephthalate reinforced with 10 % glass fiber (PBT/GF), which is induced by dual-wavelength through a home-made setup. First, the spectral properties of PC and PBT/GF are investigated to analyze optical differences at wavelengths of 980 nm and 1710 nm. Morphological characterizations reveal a significant number of glass fibers migrated across the interface and reached the PC side, forming a robust mechanical structure. These migrated glass fibers, serving as a mechanical rivet, could increase the tensile performance of the joints along with interfacial fusion bonding. Furthermore, the simulated temperature field indicates that employing a 980 nm laser effectively increases the welding temperature while preventing the thermal decomposition of the materials. The tensile test results show that the maximum tensile force using the 1710-PC//980-PBT/GF welding method, reaching 29.80 %, 20.40 %, and 111.3 % higher than that of 980-PC, 1710-PC, and 980-PC//1710-PBT/GF joints. And the corresponding displacement achieves 2.0-fold, 1.5-fold, and 4.0-fold increases compared to the above control groups. The fracture surface of the substrate and interfacial failure validate that the improved mechanical performance of joints could be attributed to the formation of a mechanical riveting structure. This paper verifies that dual laser beams could properly regulate the welding temperature field, control the morphology, and enhance the joint’s final performance.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ADHESIVE DENTISTRY
·
2024
·
IF 2.5
Zhenyu Yang,Jing Gao,Kai Tang,Longyan Duan,Shiqi Dai,An Chen,Wei Zhou,Jihua Chen
Purpose: To evaluate the effect of urethane methacrylate precursor (UMP) on the enzymatic resistance of demineralized dentin (DD) matrices. Materials and Methods: Experimental treatments containing 0 (control), 1, and 5 mmol/L UMP dissolved in an acetone (Ace) solution were formulated. Dentin matrix specimens were demineralized in vitro and immersed in the experimental treatments for 1 h. The treated specimens were then stored in 0.1 mg/mL collagenase solution for 24 h, after which their dry mass loss and hydroxyproline (HYP) release were assessed. The swelling ratios of specimens in each group were also evaluated. The interaction between UMP and the dentin matrix was observed using field-emission scanning electron microscopy (FE-SEM). Endogenous enzyme activity in dentin was evaluated using confocal laser scanning microscopy (CLSM). Results: Compared with the other treatment groups, treatment with 1 mM and 5 mM UMP-Ace significantly decreased the dry mass loss, HYP release and swelling ratio of the DD matrix (p < 0.05). FE-SEM and CLSM observations showed that treatment with UMP-Ace protected the structure of the dentin matrix and decreased porosity within the dentin-collagen network. Conclusion: Treatment with 1 mM and 5 mM UMP-Ace protects DD matrix against collagenase degradation and may be clinically useful for improving the durability of the hybrid layer.
研究领域:
口腔材料学
·
生物材料
·
修复牙科
·
生物医学工程
✓ 已验证
DOI
PubMed
高影响因子
SYNTHETIC COMMUNICATIONS
·
2020
·
IF 1.796
Xiaoyun Ma,Zhiyuan Liang,Xiuhai Gan,Gang Wei,Qingdi Zhou
Obtucarbamate A was purified from Disporum cantoniense with good antitussive property. In present work, a series of obtucarbamate A derivatives were designed and synthesized from obtucarbamate A by microwave method, and their antitussive activity were evaluated. The results showed that the toluene diisocyanate was obtained with a yield of 95.1% using a simple method, 1-methyl-2-pyrrolidinone as solvent, temperature of 190 °C, microwave irradiation at 60 W power for 30 min. All compounds have good antitussive activity, and small steric hindrance unsaturated groups of ester chains and amino groups favor activity. It is the first reported of obtucarbamate A derivatives used as antitussive, and the results provide a basis for the application of obtucarbamate derivatives as new antitussive.
研究领域:
药理学
·
有机合成化学
✓ 已验证
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2024
·
IF 4.9
Yunliang Jiang,Yumin Dong,Yong Xiong,Jun Li,Jianping Zhou,Hongbo Liang,Binghua Zhou,Bing Xie
To meet the non-removable application scenarios of most integrated electronics, the development of polymer-based packaging materials possessing superior thermal conductivity and self-healing characteristics simultaneously is necessary. However, on account of the complexity of composite structure and composition , its self-heal remains a formidable challenge. Herein, we have designed a self-healing and thermally conductive bi-functional polyurethane composites with Diels-Alder structure (PUDA) and silver nanowires (AgNWs). The hydrogen-bonding network at the interface of AgNWs and PUDA facilitated the dispersion of AgNWs in the matrix, which endows the composites with desirable thermal conductivity . Incorporating 3, 6, 9, 12, and 15 wt% of AgNWs into PUDA leads to increases in thermal conductivity of 33%, 104%, 154%, 321%, and 371%, respectively. In particular, the novel composites incorporated 12 wt% AgNWs exhibited the most efficient balance between self-healing efficiency and thermal conductivity performance. The thermal conductivity of PUDA/AgNWs with 12% of AgNWs content is 1.01 W/mK, which is 4.8 times that of PUDA (0.21 W/mK). After two reconstitution cycles, the thermal conductivity of PUDA/AgNWs-12 was restored to 85%. This study demonstrates the successful preparation of composites possessing both desirable thermal conductivity and self-healing capabilities, rendering them suitable for use as thermal interface materials in thermal management systems and flexible electronics applications.
研究领域:
材料科学
·
纳米技术
·
热管理
✓ 已验证
DOI
高影响因子
COMPOSITES PART A-APPLIED SCIENCE AND MANUFACTURING
·
2022
·
IF 9.463
Mei Wan,Congling Shi,Xiaodong Qian,Yueping Qin,Jingyun Jing,Honglei Che,Fei Ren,Jian Li,Bin Yu
In this study, three-dimensional flower-like Ni-MOFs were fabricated and successfully functionalized on multi-terminal lamellar MXene (Ti 3 C 2 T x ) by solvothermal method, and their flame retardant application in thermoplastic polyurethanes (TPU) was investigated. As expected, the addition of Ni-MOF@Ti 3 C 2 T x can improve the flame retardancy and smoke suppression properties of TPU. The heat release rate, the smoke release rate, total smoke production, CO and CO 2 release of the composite with only 1 wt% MOF@Ti 3 C 2 T x were significantly reduced by 15%, 44%, 26%, 18%, and 8%, respectively. Furthermore, the carbon residues of TPU/Ni-MOF@Ti 3 C 2 T x composites were about 2–5 times that of pure TPU, indicating that the Ni-MOF@Ti 3 C 2 T x can inhibit the thermal degradation of TPU. The mechanism illustrated that the excellent fire safety properties of TPU/Ni-MOF@Ti 3 C 2 T x composites are due to the physical barrier, catalytical carbonization, and gas-phase flame retardant of Ni-MOF@Ti 3 C 2 T x . In this work, the dispersity, thermal stability, and flame retardancy of MXene were improved due to the modification of MXene with Ni-MOF by chemical bonding and physical adsorption, which can broaden the range of applications of MOFs .
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）