Frontiers in Chemistry
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2019
·
IF 3.782
Bashir Muhammad Sohail,Jiang Xubao,Li Shusheng,Kong Xiang Zheng
Owing to their high specific surface area and low density, porous polymer materials are of great importance in a vast variety of applications, particularly as supports for enzymes and transition metals. Herein, highly uniform and porous polyurea microspheres (PPM), with size between 200 and 500 μm, are prepared by interfacial polymerization of toluene diisocyanate (TDI) in water through a simple microfluidic device composed of two tube lines, in one of which TDI is flowing and merged to the other with flowing aqueous phase, generating therefore TDI droplets at merging. The polymerization starts in the tube while flowing to the reactor and completed therein. This is a simple, easy and effective process for preparation of uniform PPM. Results demonstrate that the presence of polyvinyl alcohol in the aqueous flow is necessary to obtain uniform PPM. The size of PPM is readily adjustable by changing the polymerization conditions. In addition, palladium is incorporated in PPM to get the composite microspheres Pd@PPM, which are used as catalyst in degradation of methylene blue and rhodamine B. High performance and good reusability are demonstrated. Monodispersity, efficient dye degradation, easy recovery, and remarkable reusability make Pd@PPM a promising catalyst for dye degradation.
研究领域:
材料科学
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环境科学
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化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INDUSTRIAL CROPS AND PRODUCTS
·
2019
·
IF 4.191
Wei Guo,Hui He,Hongxiang Zhu,Xudong Hou,Xingjuan Chen,Shile Zhou,Shuangfei Wang,Lingtao Huang,Jiehan Lin
A biomass cellulose-based colorimetric sensor for Ag + and Cu 2+ was prepared by grafting 2,5-dithiourea (DTu) onto biomass-pulp cellulose. The as-prepared sensor (cellulose-DTu) showed excellent selectivity and sensitivity towards Cu 2+ over other common metal ions (Pb 2+ , Mn 2+ , Mg 2+ , Zn 2+ , Hg 2+ , K + , Al 3+ , Ca 2+ , Na + , Cd 2+ , Ni 2+ , Ba 2+ , and Li + ), exhibiting a color change from white to light grey. However, the sensor exhibited a remarkable color change from white to yellow-red upon the addition of Ag + . The naked-eye-detection concentration limits for Ag + and Cu 2+ were 10 −3 and 10 -4 mol/L, respectively. Furthermore, cellulose-DTu responded to both Ag + and Cu 2+ within 5 s. A mechanism for the selective identification of Ag + and Cu 2+ by cellulose-DTu was proposed based on 13 C solid NMR, XPS, and TEM analyses. In addition, the application of cellulose-DTu in real water confirmed that it exhibits the advantages of simplicity, rapidity, and high selectivity for in-situ identification of Ag + and Cu 2+ .
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
Applied Sciences-Basel
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2019
·Vol. 9
·期 3
·599
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IF 2.217
Kai Zhang,Qian Zhou,Hai-Mu Ye
Paraffin, the most common phase change material, has been widely utilized as the core component in thermal energy storage in the form of microcapsules. In this study, semi-crystalline paraffin is capsulated into a poly(urea-formaldehyde) (PUF) shell by a two-step polymerization process. To obtain the microcapsule with good morphology and high latent heat, sodium chloride and crosslinker (a mixture of ammonium chloride and resorcinol with a weight ratio of 1:1) are incorporated and their addition amounts were optimized through differential scanning calorimetry (DSC) and SEM. The optimized microcapsules were obtained by adding 4 wt% sodium chloride, and 0.25 wt% crosslinker exhibits a diameter of several microns and a melting enthalpy of 110 J/g. This detailed study shows that sodium chloride strongly affects the morphology of paraffin emulsion by enlarging droplets, widening the size distribution, and enhancing the stability, which should be attributed to the enhancement of electric double layer strength. In addition, sodium chloride can weaken the Zeta potential of prepolymer and provides more opportunity for prepolymer to deposit on the surface of emulsion droplets. The two components in crosslinker play different roles in the polymerization process. Ammonium chloride reacts with prepolymers and reduces the pH of system, which can accelerate the curing process, while resorcinol probably participates in polymerization as a comonomer.Keywords:Paraffin;Poly(urea-formaldehyde);Phase change microcapsules;Sodium chloride;Crosslinker
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
CHINESE JOURNAL OF POLYMER SCIENCE
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2014
·Vol. 32
·期 7
·931-940
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IF 1.42
Liu Rui-yuan,Zhang Tong,Yang Xiao-dong,Yan Yi-chen,Qu Jin-qing
A novel phenylacetylene derivative containing urea groups was synthesized and polymerized with a Rh catalyst to give the corresponding polymer, poly( 1 ) with moderate number-average molecular weights. The poly( 1 ) was soluble in toluene, CHCl 3 , CH 2 Cl 2 , THF, DMF, and DMSO, but insoluble in hexane, diethyl ether and MeOH. The specific rotation and circular dichroism (CD) spectroscopic studies revealed that poly( 1 ) took predominantly one-handed helical structures. The presence of intramolecular hydrogen bonding was confirmed by liquid-state IR spectroscopy. The helicity of poly( 1 ) could be tuned by temperature and anion. The helical conformation of the polymer was stable against Br- but susceptible to F − .
研究领域:
有机化学
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高分子化学
✓ 已验证
产品关联
DOI
高影响因子
SUPRAMOLECULAR CHEMISTRY
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2015
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IF 2.394
Bo Xiao,Ying Fan,Ning-Ning Ji,Xiao-Jie Cheng,Chuan-Zeng Wang,Jia-Jia Zhou,Sai-Feng Xue,Zhu Tao,Qian-Jiang Zhu
Using the one-pot, direct strategy reported by Su and co-workers, we have synthesised a series of cucurbit[n]urils (Q[n], n = 5–8) and alkyl-substituted cucurbit[6]urils (SQ[6]s) anchored on polymers. Acrylamide, as a typical monomer, was used to synthesise a series of Q[n]s (n = 5–8) and SQ[6]-anchored polyacrylamides (PAMs) using a persulfate salt as initiator and oxidant. The Q[n]s (n = 5–8) and SQ[6]-anchored PAM samples have been characterised by 1H NMR, 1H NMR titrations of probe guests, Fourier-transform infrared and thermogravimetric analyser. The results confirmed that PAM chains had been successfully grafted on the back of the Q[n]s (n = 5–8) and SQ[6]s through an in situ radical polymerisation approach. It was further confirmed that the hydrophobic cavities of the Q[n]s on the polymers were still freely accessible. This synthetic approach may be extended to a variety of Q[n]s that are difficult to functionalise.
研究领域:
高分子化学
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超分子化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of CO2 Utilization
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2017
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IF 4.292
Zhong Ying,Chaoyong Wu,Chao Zhang,Shan Jiang,Ruhui Shi,Haiyang Cheng,Bin Zhang,Yan Li,Fengyu Zhao
A series of polyureas were synthesized with CO 2 as the carbonyl building block, which consist of a hard segment of CO 2 -based oligourea and a soft segment of soluble polyether diamine. The hard segment was formed from 1,3-bis(3-aminopropyl) tetramethyl disiloxane with CO 2 , and the soft segment was obtained through polyaddition of polyether diamine with an extender agent. The Number-average Molecular Weight (Mn) and Weight-average Molecular Weight (Mw) were estimated by Gel permeation chromatography (GPC). The properties of the synthesized polyureas such as thermo-stability and the tensile strength were examined, and these properties could be adjusted by varying the molecular weight of polyether diamine and oligourea segments. The synthesized polyureas have an amorphous structure and presented satisfied thermo-stability (∼250 °C) and the high tensile strength (22.4 MPa).
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
REACTIVE & FUNCTIONAL POLYMERS
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2022
·
IF 4.966
Ruyue Wang,Xingxing Chen,Yuxuan Yang,Yongliang Xu,Qiang Zhang,Yanfeng Zhang,Yilong Cheng
Hydrogels with outstanding mechanical characteristics , remoldability, and self-healability possess vast potentials in biomedical applications and flexible sensors. However, it is still difficult to prepare hydrogels with integrated mechanical characteristics straightforwardly. Herein, we proposed to introduce a hydrogen bonding reinforced factor, imidazolidinyl urea (IU), to the polymerization of acrylamide for the construction of multi-functional hydrogels in one pot. There are multiple hydrogen bonding donors and receptors in IU, which can interact with polyacrylamide through multiple hydrogen bonds to form the hydrogel networks. The break strength, fracture elongation, and compressive strength of the IU-included hydrogels could be adjusted in the range of 18.8–23.8 kPa, 305%–560%, and 2.0–3.9 MPa, respectively. The hydrogels featured outstanding fatigue resistance , and the obvious loss of compressive strength was not observed even after 50 cycles of loading-unloading under 85% strain. Moreover, the IU-based hydrogels not only showed promising self-healing and remodeling abilities but also exhibited nonconventional emission behaviors. Our work offers a facile strategy for the construction of multi‑hydrogen bond crosslinked hydrogels and may inspire researchers to explore new supramolecular systems using the hydrogen bonding reinforced factor (IU).
研究领域:
材料科学
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生物医学工程
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产品关联
DOI
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
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2018
·
IF 2.196
Yanxiao Zhao,Haiyan Yang,Zeren Shang,Tingting Gong,Xu Zhang,Songgu Wu
Glibenclamide (GCM) is an oral antihyperglycemic drug and widely used to treat type-II diabetes. The quality of the GCM product impacts the efficacy of the medicine. However, the quality of the product is determined by the crystallization process, in which the solubility property plays a significant role. In this study, GCM solubility in 11 monosolvents (methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, acetone, acetonitrile, methyl isobutyl ketone, methyl acetate and ethyl acetate) and (acetone + acetonitrile) binary solvents, has been determined through a gravimetric method from 283.15 K to 323.15 K. It elucidates that GCM has the highest solubility in acetone among the 11 monsolvents. Meanwhile, the solubility of GCM in (acetone + acetonitrile) binary solvents increases when the mole fraction of acetone rises. Then, we correlated the solubility data in monosolvents using the modified Apelblat model and nonrandom two-liquid (NRTL) model. Besides, the modified Apelblat model, the CNIBS/R-K model, Jouyban–Acree model, and NRTL model were adopted to fit the data in (acetone + acetonitrile) mixture solvents. Furthermore, thermodynamic properties were calculated on the basis of the NRTL model.
研究领域:
药物化学
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物理化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
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2021
·
IF 2.694
Guangyu Xu,Fanyuan Zhang,Zhenghui Li
As a common solvent, water cannot dissolve flufenoxuron in this study well; therefore, methanol was added to the water to form a liquid mixture of different compositions. At first, the ratio of methanol mass was 90%, and then, it decreased by 10% until the methanol content was 10%. According to the above method, n-propanol, propylene glycol, and N,N-dimethyl formamide were made into corresponding mixed solvents. Under a pressure of 101.2 kPa, the temperatures of flufenoxuron and the solvent were kept at 278.15 K. Based on the basic principle of the static gravimetric method, the amount of solute diffusion in the above four mixed solvents was obtained. Other conditions remained unchanged, the temperature was increased by 5 K, and the above steps were repeated until the temperature was 323.15 K. There were two variables in the experiment; the temperature changes to a higher level and more flufenoxuron can be detected in the solution. Regardless of the change in temperature variables, the larger the mass of the organic solvent, the more solutes in the solution. Three models were employed to calculate the solubility of flufenoxuron. The maximum results of relative average deviation and the root-mean-square deviation were 0.43% and 4.24 × 10–4.
研究领域:
化学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL CROPS AND PRODUCTS
·
2023
·
IF 5.9
Dicheng Ma,Tao Zhang,Guoxian Wang,Chong Cao,Wei Mu,Beixing Li,Daolong Dou,Feng Liu
Trans -2-hexenal (T2H) shows satisfactory antagonistic activity against Fusarium graminearum , but its strong volatility and poor water solubility limit its further application in Fusarium head blight (FHB) control. In this study, T2H-loaded polyurea microcapsules (PU MCs) with different particle sizes were successfully prepared by an interfacial polymerization method, and the effect of MC encapsulation on the physical property limitations and bioactivity of T2H was evaluated. After being encapsulated, lipophilic T2H could be stably dispersed in water. MC encapsulation reduced the fumigation toxicity of T2H but increased its contact toxicity. The smaller the particle size was, the higher the toxicity of PU MCs to F. graminearum was. After 6 d of application, the inhibition rate of T2H against F. graminearum decreased by 77.26%, while that of T2H-loaded PU MCs with small particle sizes (T2H-loaded PU MCs-S) decreased by 54.29%, indicating that MC encapsulation prolonged the inhibition time of T2H. The results of the inoculation assay showed that MC encapsulation improved the inhibitory effect of T2H on F. graminearum infection and DON production in stored wheat kernels. Furthermore, seed soaking with T2H-loaded PU MCs-S reduced the pathogenic fungal load of wheat seeds and had no significant effect on seed germination. In conclusion, T2H encapsulated in MCs can be developed as a plant protection product for postharvest and presowing treatment of wheat.
研究领域:
植物保护
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真菌学
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农药科学
✓ 已验证
产品关联
DOI
高影响因子
MACROMOLECULAR RESEARCH
·
2023
·Vol. 31
·期 6
·603-613
·
IF 2.4
Gu Jianbo,Wang Xiang,Xu Chengze,Feng Xiangyang,Zhang Siyuan
In recent years, high refractive index polythiourethane materials have attracted increasing attention. In this study, the soft segment part of conventional polyurethane was replaced by ethylenedithiol, and a series of nanocomposite films containing Mercaptoethanol (ME) capped ZnS NPs were prepared by UV curing after the synthesis of the bifunctional linear prepolymer with hydroxyethyl acrylate as capping agent and trifunctional prepolymer with trimethylolpropane triacrylate as sulfhydrylate capping. ZnS NPs were well dispersed in the resin system, and the transmittance of the film decreased with the increase of ZnS content, but it did not float much and still has 80% transmittance at 40%. The addition of ZnS had a significant improvement on the refractive index. The RI of the system without the addition of particles was less than 1.5, the system with 40% was greater than 1.6. It was worth noting that the Abbe number was almost greater than 30, which was in the category of low dispersion.
Graphical abstract
Preparation of highly refractive polythiourethane-ZnS composite film by “click” chemical reaction
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Xueqin Zhang,Qiaoyu Meng,Keqiang Zhang,Rongqi Zhu,Zhaoliang Qu,Ying Li,Rujie He
Ceramics are attractive for structural components because of their excellent load-bearing capacity. Nevertheless, inferior energy-absorbing ability and poor reliability under common quasi-static and dynamic environments, especially under cyclic loading, extremely limit the popularization of ceramic components. The coupling between cellular structures inspired by the light but strong porous trabeculae and core–shell structure in strong and tough natural materials provides a solution for strengthening the load-bearing capacity, energy absorption ability, and cyclic life of ceramic components. Here, we proposed a bioinspired cellular ceramic structure/polyurea (CCS/polyurea) dual-phase architecture via additive manufacturing and simple infiltration technologies. It was demonstrated that the specific load-bearing capacity and energy-absorbing ability of bioinspired CCS/polyurea dual-phase architecture under quasi-static compressive loading were 2.22 and 50.34 times of CCS, respectively. Significantly, it could be repeatedly loaded at 40.28 and 48.82 MPa for over 120 and 8 cycles, respectively. Furthermore, CCS/polyurea dual-phase architecture performed extraordinary cyclic life under dynamic loading. The cyclic lives of CCS/polyurea dual-phase architecture at impact speeds of ∼ 6 and ∼ 12 m/s reached as high as 11 and 2, respectively. This research provides a credible approach to building ceramic-based materials with extraordinary load-bearing capacity, energy absorption ability, and especially remarkable cyclic life.
研究领域:
材料科学
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仿生学
✓ 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）