APPLIED SURFACE SCIENCE
·
2018
·
IF 4.439
Haihua Wang,Bei Li,Guiqiang Fei,Yiding Shen,Ke Zhu
We reported herein the synthesis of block copolymers and their application in the in-situ emulsion polymerization of waterborne poly (urethane-acrylate) (WPUA) nanoemulsions based on phase inversion process. The polymerizable surfmers containing terminal unsaturated double bonds (MSA-r) were successfully synthesized via catalytic chain transfer polymerization (CCTP). Random copolymer (MSA-t) prepared through radical polymerization was utilized as control. The structure, surface tension and aggregation behavior of surfmers were characterized. The phase inversion, formation and stability of WPUA nanoemulsions were systematically investigated. Effects of MSA-r surfmer content and BMA/MMA ratio on the water resistance and thermal stability of the corresponding films were also discussed. It was found that the phase inversion mechanism of PUA prepolymer in the presence of MSA-r surfmers is different from conventional polyurethane prepolymer. The addition of MSA-r and MSA-t surfmers alters the rheological behaviors of PUA prepolymer via PUA-surfmer interactions, as well as the phase inversion process. Compared with WPUA/MSA-t emulsion, WPUA/MSA-r nanoemulsion displayed improved stability at higher solid content. The minimum particle size of WPUA/MSA-r nanoemulsion was 88.7 nm and kept almost constant after 12-month storage, while the particle size of WPUA/MSA-t emulsion was 131.3 nm and increased to 178.9 nm. Moreover, the WPUA/MSA-r film possessed improved water resistance and thermal stability.
研究领域:
高分子化学
·
胶体与界面科学
·
材料化学
·
纳米材料
·
功能高分子
·
水性涂料
·
聚合物乳液
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2013
·Vol. 131
·期 9
·
IF 1.395
Chang Su,Dezhen Zong,Lihuan Xu,Cheng Zhang
In this article, semi-interpenetrating polymer network (Semi-IPNs) based on nitrile rubber (NBR) and poly(methyl methacrylate- co -butyl acrylate) (P(MMA-BA)) were synthesized. The structure and damping properties of the prepared Semi-IPNs blends were characterized and by fourier transform infrared spectrum (FTIR), dynamic mechanical analysis (DMA), scanning electron microscopy (SEM), thermogravimetric analysis (TGA/DTG), and tensile mechanical properties. The results showed that interpenetrating network based on P(MMA-BA) and NBR was successfully obtained, which showed the improved thermal stability compared to NBR/P(MMA-BA)-based two-roll mill blends. Furthermore, Semi-IPNs showed significantly better the dynamic mechanical properties than that of the two-roll mill system. With the increasing feed ratio of BA and MMA during the preparation of Semi-IPNs, the loss peak position for P(MMA-BA) in NBR/PMMA IPNs shifted to a lower temperature from 20°C to −17°C, and when NBR in Semi-IPNs was accounted for 40 wt %, the dynamic mechanical thermal analysis showed that much more advanced damping material with wider temperature range (−30°C < T < 80°C) as tan δ > 0.45 can be achieved. Therefore, it was expected as a promising way to obtain the excellent damping materials with good oil-resisted properties according the Semi-IPNs system. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131 , 40217.
研究领域:
高分子材料科学
·
功能材料
·
复合材料
·
材料物理
·
阻尼材料
·
聚合物改性
✓ 已验证
DOI
高影响因子
TETRAHEDRON-ASYMMETRY
·
2010
·
IF 2.625
Zhen-Wei Zhang,Gui Lu,Miao-Miao Chen,Ning Lin,Yong-Bo Li,Tamio Hayashi,Albert S.C. Chan
The first asymmetric Mannich-type reaction of methyl isocyanoacetate with N -sulfonylimines catalyzed by cinchona alkaloid derivatives yielded 2-imidazolines with high diastereoselectivities and good enantioselectivities (up to >99:1 dr and 70% ee). This reaction provided a convenient route to access various substituted 2-imidazoline-4-carboxylates and related α,β-diamino acids in high enantiomeric purities.
研究领域:
有机化学
·
药物化学
·
不对称合成
·
催化化学
·
生物有机化学
✓ 已验证
DOI
高影响因子
JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY
·
2012
·Vol. 50
·期 24
·5177-5184
·
IF 3.919
Yonggang Gao,Lin Gu,Yusheng Qin,Xianhong Wang,Fosong Wang
Low-molecular weight oligo(carbonate-ether) diols are important raw materials for polyurethane formation, which with tunable carbonate unit content (CU) may endow new thermal and mechanical performances to polyurethane. Herein, facile synthesis of oligo(carbonate-ether) diols with number average molecular weight ( M n ) below 2000 g mol −1 and CU tunable between 40% and 75% are realized in high activity by immortal copolymerization of CO 2 /propylene oxide (PO) using zinc-cobalt double metal cyanide complex (Zn-Co-DMCC) in the presence of sebacic acid (SA). M n of the oligomer is in good linear relationship to the mole ratio of PO and SA (PO/SA) and hence can be precisely controlled by adjusting PO/SA. Besides, the molecular weight distribution is quite narrow due to the rapid reversible chain transfer in the immortal copolymerization. High pressure and low temperature are favorable for raising CU. In all the reactions, the weight fraction of propylene carbonate ( W PC ) can even be controlled as low as 2.0 wt %, and the catalytic activity of Zn-Co-DMCC is above 1.0 kgg −1 cat. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
研究领域:
高分子化学
·
催化化学
·
绿色化学
·
功能材料
·
聚合物合成
·
二氧化碳利用
✓ 已验证
DOI
高影响因子
IONICS
·
2023
·Vol. 29
·期 11
·4669-4679
·
IF 2.8
Tang Liping,Wu Yankang,Lei Zhiqiang,He Yu,Chen Jian
An in situ–grown TiO 2 membrane was prepared by an electrospinning method using polyacrylonitrile as the spinning precursor, combined with the TiO 2 hydrolysis mechanism. The performance of tetrabutyl titanate and isopropyl titanate as two titanium source precursors hydrolyzed under the inhibition of acrylic acid to produce TiO 2 with different contents for lithium-ion batteries was compared. The experimental results showed that when both titanium sources were prepared at 3 wt%, the comprehensive performance of the separator manufactured with tetrabutyl titanate as the titanium source (PAN/TBT-3) and isopropyl titanate as the titanium source (PAN/TPT-3) was finest than that of the Celgard 2400 and the composite membrane with direct TiO 2 addition (PAN/TiO 2 -3). The tensile strength of PAN/TPT-3 and PAN/TBT-3 membranes were 7.82 MPa and 4.03 MPa higher than that of Celgard 2400, and 17.03 MPa and 13.29 MPa higher than that of PAN/TiO 2 -3 separator, respectively. PAN/TPT-3 and PAN/TBT-3 membranes exhibited a discharge capacity of 107.72 mAh/g and 115.79 mAh/g at 2 C, and both the capacity retention rate was above 99.5% higher than 80.5% for Celgard 2400.
研究领域:
材料科学
·
纳米技术
·
储能
·
电化学
✓ 已验证
DOI
高影响因子
AATCC Journal of Research
·
2025
·
IF 1.2
Yanxia Xie,Weiqiang Zhang,Yaning Xu,Shuhan Zhao,Wenxuan Yin,Wenqiang Zhang,Xu Han,Hongmei Zuo,Lihua Zou
Polyethylene terephthalate (PET) fibers have been widely used in various industrial fields due to their excellent chemical and physical performance. However, there is still a crucial problem of the massive precipitation of oligomers from the interior to the surface of product, which results in decreased production efficiency and harm to human health. A quantitative characterization method for surface oligomers of PET fibers based on Soxhlet extraction was developed, with lower-temperature extraction, high accuracy, excellent extraction effect and wider operability. The extraction temperature (Toe) decreased by 30°C compared to the conventional extractant of tetrachloroethylene (Te-Ex), benefiting from the trichloroethylene (Tr-Ex) extractant. The pre-wash process with trichloroethylene could ideally remove oil impurities of about 0.09% but retain the surface oligomers on the fibers, endowing the method of with promising accuracy. PET staple fibers with various contents of surface oligomers were extracted with Tr-Ex, and the achieved contents (i.e. 0.320%/0.527%/0.876%) were similar to those with Te-Ex (i.e. 0.307%/0.516%/0.828%), and the contents with Tr-Ex were all slightly higher than those with Te-Ex, indicating that the extraction efficiency of Tr-Ex improved by ∼4.10% compared with that of Te-Ex. It was confirmed that Tr-Ex method has excellent accuracy compared with as the Te-Ex method and better extraction effect than the Te-Ex method; maybe possibly dipole–dipole interaction between trichloroethylene and oligomer molecules was responsible for the better effect. This quantitative characterization method has potential application in industrial online measurement of surface oligomers on PET fibers, films and related materials.
研究领域:
高分子科学
·
材料工程
·
分析化学
·
工业化学
✓ 已验证
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2021
·
IF 3.764
Yingchao Cai,Chunmei Li,Yumin Yang,Haonan Li,Yuhang Wang,Qiuyu Zhang
Owing to excessive energy consumption and environmental deterioration, thermosets with permanent covalent crosslinks have encountered unprecedented challenge in the sustainable development. An effective method to address this intractable problem is to construct covalent adaptive networks that contain dynamic covalent bonds. Herein, self-healable and reprocessable cross-linked poly(urea-urethane) elastomers with high mechanical performance were simply developed by introducing dynamic oxime–carbamate bonds (POUUs). The studies on nuclear magnetic resonance indicated that the sufficient exchange rather than the reversible dissociation of oxime–carbamate bonds was the key to network arrangement at elevated temperatures. Due to the incorporation of strong polar urea bonds, POUUs showed excellent mechanical performance with a tensile strength of 27.8 MPa and toughness of 52.5 MJ m–3. The good self-healing ability of POUUs was demonstrated by the disappearance of scratches at 80 °C after 15 h. All POUUs were easily remolded (130 °C, 5 MPa) into transparent films with a maximum recovery efficiency of 80%. Furthermore, complete dissolution in N,N-dimethylformamide was achieved at 100 °C after 4 h, exhibiting high recyclability of the cross-linked POUUs.
研究领域:
高分子科学
·
材料工程
·
化学合成
·
可持续发展
·
力学性能研究
✓ 已验证
DOI
高影响因子
JOURNAL OF CHROMATOGRAPHY B-ANALYTICAL TECHNOLOGIES IN THE BIOMEDICAL AND LIFE SCIENCES
·
2011
·
IF 2.971
Wei Liu,Jurui Qi,Linna Yan,Qiong Jia,Cong Yu
This paper presents a study of the synthesis of a polymer monolith column and its application to the analysis of PAHs in smoked meat products. A poly(butyl methacrylate-co-ethylene glycol dimethacrylate) monolith capillary has been successfully prepared with in situ polymerization method. The polymer monolith microextraction combined with HPLC determinations is employed for the analysis of naphthalene , biphenyl , phenanthrene , and anthracene . Various parameters affecting the extraction efficiency have been investigated and optimized. Under the optimum experimental conditions, the method provides an acceptable linearity (2–10,000 μg/L), low limits of detection (1.4–2.0 μg/L), and good precision (intraday relative standard deviations < 4.1%, interday relative standard deviations < 5.7%). When applied to the determination of the four PAHs in smoked meat samples, recoveries are obtained in the range of 86.6–101.5%.
研究领域:
分析化学
·
食品科学
·
环境科学
✓ 已验证
DOI
高影响因子
Materials Chemistry Frontiers
·
2021
·Vol. 5
·期 14
·5371-5381
·
IF 6.482
Qianyun Zhong,Xingxing Chen,Yuxuan Yang,Chenhui Cui,Li Ma,Zhen Li,Qiang Zhang,Xiaoming Chen,Yilong Cheng,Yanfeng Zhang
Transparent and degradable polyurethane elastomers with high strength and toughness are in demand for various applications, such as tissue engineering and flexible electronics. However, designing specific chemical structures is challenging, and thus fabricating novel elastomers is sometimes unattainable. An effective approach to develop elastomers is through the introduction of sacrificial bonds, e.g. hydrogen bonds, to enhance their mechanical properties and toughness, which provide hidden lengths and hierarchical structures for energy dissipation. This study introduced a facile and efficient strategy by employing imidazolidinyl urea (IU) as a multiple hydrogen-bonding motif to fabricate transparent and degradable polyurethane elastomers (PHI) with superior breaking strength and excellent toughness. The resultant breaking strength and toughness reached up to 24.9 MPa and 168.2 MJ m−3, respectively. Additionally, the breaking strength increased to 49.9 MPa after the sample was pre-stretched to 600% strain due to strain-induced crystallization (SIC). Moreover, the PHI film with degradability and good biocompatibility showed potential application in post-operative anti-adhesion.
研究领域:
材料科学
·
生物医学工程
·
高分子化学
✓ 已验证
DOI
高影响因子
Polymer Crystallization
·
2020
·Vol. 3
·期 3
·e10130
·
IF 0
Dachuan Ding,Jingjin Luo,Jie Wang,Zixin Yu,Yuanfu Tian,Jinqiang Tan,Zhiyuan Song,Qian Tao,Tao Hu,Chonggang Wu
Ionized polyamide (PA)-66 was successfully prepared at room-temperature using HCl (0.31 mol%) and CaCl 2 (2.3 mol%), respectively. The PA-66 ionenes, compared with the non-ionized PA-66, are used as a nucleator along with cholesteryl nonanoate (CN) as an active plasticizer to improve poly(bisphenol-A carbonate) (PC) crystallization. The results show the PA-66-HCl heterogeneously nucleates PC more effectively than the PA-66-CaCl 2 . The possible rationale is that the strong ion-dipole interactions (IDIs) of the PA-66-HCl remarkably boost the PC/PA-66-HCl interfacial compatibility, which results in the formation of considerably finer and denser PA-66-HCl crystals with significantly enhanced nucleation efficiency. However, owing to its higher ion content, the PA-66-CaCl 2 seems to have much stronger IDIs with PC that the resulting compatibility (i.e., thicker amorphous interlayers) dramatically inhibits PC crystallization.
研究领域:
材料科学
·
高分子化学
✓ 已验证
DOI
JOURNAL OF ENZYME INHIBITION AND MEDICINAL CHEMISTRY
·
2019
·
IF 4.027
Yu-Heng Hu,Jie Yang,Yun Zhang,Ke-Chun Liu,Teng Liu,Jie Sun,Xiao-Jing Wang
The work is focused on the design of drugs that prevent and treat Alzheimer’s disease (AD) and its complications. A series of 3–(4-aminophenyl)-coumarin derivatives designed, synthesised, fully characterised and evaluated in vitro/vivo. The biological assay experiments showed that some compounds displayed a clearly selective inhibition for acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE). Among all compounds, compound 4m exhibited the highest AChE inhibition with an IC50 value of 0.091 ± 0.011 µM and compound 4k exhibited the highest BuChE inhibition with an IC50 value of 0.559 ± 0.017 µM. A zebrafish behaviour analyser (Zebrobox) was used to determine the behavioural effects of the active compound on the movement distance of the aluminium chloride-induced zebrafish. Compound 4m offered a potential drug design concept for the development of therapeutic or preventive agents for AD and its complications.
研究领域:
药理学
·
神经科学
·
药物设计
✓ 已验证
DOI
PubMed
高影响因子
MOLECULES
·
2019
·Vol. 24
·期 7
·1311
·
IF 3.06
Ming-Jie Chu,Wei Wang,Zi-Li Ren,Hao Liu,Xiang Cheng,Kai Mo,Li Wang,Feng Tang,Xian-Hai Lv
To develop new antibacterial agents, a series of novel triazole-containing pyrazole ester derivatives were designed and synthesized and their biological activities were evaluated as potential topoisomerase II inhibitors. Compound4dexhibited the most potent antibacterial activity with Minimum inhibitory concentration (MIC) alues of 4 µg/mL, 2 µg/mL, 4 µg/mL, and 0.5 µg/mL againstStaphylococcus aureus,Listeria monocytogenes,Escherichia coli, andSalmonella gallinarum, respectively. The in vivo enzyme inhibition assay4ddisplayed the most potent topoisomerase II (IC50= 13.5 µg/mL) and topoisomerase IV (IC50= 24.2 µg/mL) inhibitory activity. Molecular docking was performed to position compound4dinto the topoisomerase II active site to determine the probable binding conformation. In summary, compound4dmay serve as potential topoisomerase II inhibitor.Keywords:pyrazole;triazole;ester;antibacterial;topoisomerase II inhibitor
研究领域:
药理学
·
微生物学
·
药物化学
✓ 已验证
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）