JOURNAL OF APPLIED POLYMER SCIENCE
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2021
·Vol. 139
·期 16
·51988
·
IF 3.125
Ye-xi Zhou,Qing-xia Yuan,Shu-ling Gong
The high molecular weight polyacrylate self-emulsifying emulsion with 20% hydroxyl monomer and 50% solid content was prepared. Waterborne polyester was used to modify the acrylate resin. Besides acrylic acid (AA) and methacrylic acid (MAA), poly(ethylene glycol) methyl ether methacrylate (PEGMEMA) was also used as functional monomer to stabilize the polymerization process and improve the properties of the emulsion. The effects of the amount of waterborne polyester (WP), ammonium persulfate (APS), poly(ethylene glycol) methyl ether methacrylate (PEGMEMA), methacrylic acid (MAA)/acrylic acid (AA) monomer ratio, butyl acrylate (BA)/styrene (St) monomer ratio on the molecular weight, particle size, viscosity, storage stability, and cured film properties of the polyacrylate emulsion were investigated. The average molecular weight of the modified polyacrylate was up to about 2.5 × 10 4 g mol −1 . The emulsion remained stable after 6 months at room temperature. Transmission electron microscope (TEM) images showed that the latex particles had core-shell structure. The films cured with melamine formaldehyde (MF) resin showed excellent water resistance, adhesion, and hardness.
研究领域:
材料科学
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高分子化学
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产品关联
DOI
高影响因子
PROGRESS IN ORGANIC COATINGS
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2020
·
IF 4.469
Yang Xu,Jing Luo,Xiaoya Liu,Ren Liu
Epoxy acrylate resins modified by polyurethane with excellent mechanical properties play a crucial role in UV-curable coatings, but the high viscosity limits their further applications in 3D printing, electronic packaging material. In this work, a series of polyurethane modified epoxy acrylate resins containing various ε-caprolactone unit content were successfully synthesized to reduce the viscosity of polyurethane modified epoxy acrylate resins. The chemical structure and molecular weight of the prepared resins were characterized by Fourier transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance spectroscopy ( 1 H NMR) and gel permeation chromatography (GPC), respectively. The influences of ε-caprolactone unit on the viscosity of resins and double bond conversion of cured films were studied. The dynamic thermomechanical properties, mechanical properties, thermal stability and basic properties of UV curable coatings were also evaluated. The results show that the viscosity of resins is reduced by two orders of magnitude. As the ε-caprolactone unit content increased, the adhesive force increased from 0B to 5B according to ASTM D3359, while the glass transition temperatures (Tg) of films and pencil hardness were slightly lower than those of the conventional polyurethane modified epoxy acrylate resins. In summary the introduction of ε-caprolactone unit in the side chain enables the preparation of polyurethane modified epoxy acrylate resin with ultralow viscosity as well as a more comprehensive adhesive and impact force performance.
研究领域:
材料科学
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化学工程
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产品关联
DOI
高影响因子
ACS Applied Energy Materials
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2022
·
IF 6.959
Pengfei Lv,Song Xie,Qiang Sun,Xiantao Chen,Yuanhua He
A flame-retardant solid polymer electrolyte (FR-SPE) membrane was successfully designed through UV-curing flame-retardant polyurethane acrylate (PUA) oligomers, succinonitrile, aluminum oxide (Al2O3), and lithium salt. The flame retardant PUA is formed by grafting reactive flame-retardant 9,10-dihydro-9-oxa-10-phenanthrene-10-oxide (DOPO) on the main chain of the oligomer. The cross-linked PUA ensures excellent mechanical properties and high flame retardancy of FR-SPE. Moreover, the flame retardancy of the FR-SPE can reach the V-0 level of the UL-94 test when the grafting rate of DOPO on PUA reached 39%, and the obtained FR-SPE achieves a high ionic conductivity of 2.66 × 10–4 S cm–1 at room temperature, a wide electrochemical stability window of 5 V, and a high lithium-ion transfer number of 0.55. Moreover, FR-SPE shows a stable lithium plating/stripping response for over 600 h under a constant current density of 0.1 mA cm–2. Meanwhile, the cell of LiFePO4/FR-SPE/Li4Ti5O12 has excellent cycling stability (144.6 mA h g–1 at 0.2 C after 100 cycles) and rate capability (107.4 mA h g–1 at 5 C). In addition, the electrolyte has no adverse effect on the cycle performance of batteries with graphite electrodes. Thus, such cross-linked flame-retardant SPEs are argued to provide an effective method for more broadly enhancing lithium battery safety and performance.
研究领域:
材料科学
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能源存储与转换
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产品关联
DOI
高影响因子
Journal of Coatings Technology and Research
·
2023
·Vol. 20
·期 5
·1569-1578
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IF 2.3
Ding Zhu,Chen Jiahui,He Zonglin,Wang Chaozhi,Li Hualin,Huang Zhenhong,Liu Baohua,Song Lina
A series of two-component UV-curable waterborne CO 2 -based polyurethane dispersions (UV-PUDs) with excellent flexibility and mechanical strength were synthesized from poly(propylene carbonate) diol (PPCD), isophorone diisocyanate (IPDI), 2,2-bis(hydroxymethyl) propionic acid (DMPA), 2-hydroxyethyl acrylate (HEA), pentaerythritol triacrylate (PETA) and 1,4-butanediol (BDO). One component was UV-curable waterborne polyurethane terminated by HEA and PETA (molar ratio 1:1), and the other component was linear waterborne polyurethane. The content of the UV-curable component in UV-PUD was 15%, 30%, 45%, 60%, and 100% (weight content). The obtained cured films exhibited superior flexibility without loss of tensile strength, accompanied by excellent acid and alkali resistance. In particular, the dried UV-PUD films without curing showed good mechanical properties.
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
Polymers
·
2024
·Vol. 16
·期 21
·3045
·
IF 4.7
Hairui Wang,Lan Cao,Xiaolei Wang,Xiurui Lang,Wenwen Cong,Long Han,Hongyu Zhang,Huibin Zhou,Jujie Sun,Chengzhong Zong
Polyurethane (PU) plays a critical role in elastomers, adhesives, and self-healing materials. We selected the most commonly used aromatic isocyanates, 4,4′-methylene diphenyl diisocyanate (MDI) and tolylene-2,4-diisocyanate (TDI), and the most commonly used aliphatic isocyanates, hexamethylene diisocyanate (HDI), isophorone diisocyanate (IPDI), and dicyclohexylmethane-4,4′-diisocyanate (HMDI), as raw materials, combined with polytetramethylene ether glycol (PTMG) and 1,4-butanediol (BDO) to successfully synthesize five PU materials. The effects of isocyanate structure on polymerization rate, hydrogen bonding, thermal properties, phase separation, wettability, self-healing performance, adhesion, and mechanical properties were systematically investigated. The results show that isocyanates with higher symmetry facilitate hydrogen bonding, but excessive flexibility and crystallinity may inhibit its formation. MDI-based PU exhibits the highest hydrogen bonding index (HBI) of 4.10, along with the most distinct phase separation and the highest tensile strength of 23.4 MPa. HMDI-based PU demonstrates the best adhesion properties, with the highest lap shear strength of 7.9 MPa, and also exhibits excellent scratch healing ability. IPDI-based PU shows good self-healing performance, recovering 88.7% of its original tensile strength and 90.6% of its original lap shear strength after heating at 80 °C for 24 h. Furthermore, all the samples can be reprocessed by melt or solution methods, showing excellent recyclability.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
PROGRESS IN ORGANIC COATINGS
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2015
·
IF 2.358
Jie Yi,Congshu Huang,Haiyan Zhuang,Hui Gong,Chuyi Zhang,Runtao Ren,Yupu Ma
The star-shaped polyester polyols based on initiators (trimethylolpropane or pentaerythritol) and ɛ-caprolactone were prepared by polycondensation reaction. The degradable polyurethane (PU) films were prepared by mixing star-shaped polyester polyols and crosslinker agent (hexamethylene diisocyanate trimer). The hydrolytic degradation and water absorption experiments demonstrated that the PU films could erode in artificial sea water, which were controlled by varying the ratios of ɛ-caprolactone/trimethylolpropane and the arm number of star-shaped polyester polyols. The mechanical properties of PU films and coatings increased with decreasing the ratios of ɛ-caprolactone/trimethylolpropane and increasing the arm number of star-shaped polyester polyols. The surfaces of PU films and coatings kept eroding, which were revealed by scanning electron microscopy. The copper ion release rates from PU coatings reached steady state at about 31 days. The marine field tests of PU coatings demonstrated that the degradable PU coatings based on star-shaped polyester polyols were effective coatings for marine antifouling.
研究领域:
材料科学
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海洋生物学
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化学工程
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DOI
高影响因子
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
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2021
·Vol. 22
·期 16
·8668
·
IF 5.924
Jie Li,Shiyi Wang,Huayin Li,Yuan Tan,Yunjie Ding
The synthesis of ester compounds is one of the most important chemical processes. In this work, Zn-Mg-Al mixed oxides with different Zn2+/Mg2+molar ratios were prepared via co-precipitation method and supported gold nanoclusters to study the direct oxidative esterification of aldehyde and alcohol in the presence of molecular oxygen. Various characterization techniques such as N2-physical adsorption, X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and CO2temperature programmed desorption (TPD) were utilized to analyze the structural and electronic properties. Based on the results, the presence of small amounts of Zn2+ions (~5 wt.%) provoked a remarkable modification of the binary Mg-Al system, which enhanced the interaction between gold with the support and reduced the particle size of gold. For oxidative esterification reaction, the Au25/Zn0.05MgAl-400 catalyst showed the best performance, with the highest turnover frequency (TOF) of 1933 h−1. The active center was believed to be located at the interface between metallic gold with the support, where basic sites contribute a lot to transformation of the substrate.Keywords:gold catalyst;cluster;hydrotalcite;oxidative esterification;methyl isobutyrate
研究领域:
化学工程
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催化材料
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DOI
PubMed
高影响因子
Current Research in Food Science
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2022
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IF 6.269
Zihao Wang,Ayuan Xiong,Yougui Yu,Qing Zheng
The development of low-alcohol liquor (Baijiu) can represent a tool to solve the problems of excessive alcohol intake. However, low-alcohol liquor has an insufficient ester aroma and a bland taste due to the alcohol dilution process. This study proposes an electrochemical catalysis technology to catalyze the esterification reaction between the acid and alcohol in liquor, thereby enhancing the ester aroma of low-alcohol liquor. In the electrochemical conversion process, the gold electrode with a certain potential promotes the formation of carbocation intermediate from corresponding carboxylic acid, thereby improving the esterification reaction efficiency. The key finding is that the total ester content of liquor treated using this technology is increased by more than 20%, and a strong ester aroma is attained. This study clarifies the electrocatalytic mechanism of the esterification reaction in liquor, and provides a new idea for making low-alcohol liquor become more attractive for aroma and taste aspects trying to obtain an alternative product contributing to the public health.
研究领域:
食品科学
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化学工程
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生物催化
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DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2025
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IF 11.3
Yidong Zhou,Zhijian Ke,Jiazhuo Zhang,Wenbin Chang,Yarong Cui,Yimiao Chen,Yirui Huang,Chunli Xia,Wenjia Zhong,Zifa Deng,Dayong Jin
Microorganisms are constantly evolving to resist the toxicity of artificial antibiotics and preservatives released into the environment. Parabens, a group of alkyl and aryl esters of p -hydroxybenzoate, are a class of widely used antimicrobial preservatives, particularly effective against Gram-positive bacteria and fungi. Previous studies have reported the degradation of parabens by numerous Gram-negative strains and activated sludge, with degradation processes often involving transesterification. However, the physiological significance of transesterification has received little attention. Here, a Gram-positive bacterium, Microbacterium sp. S1037 was isolated and characterized for its ability to degrade eight parabens and completely mineralize them through p -hydroxybenzoate and protocatechuate ( β -ketoadipate pathway). Moreover, strain S1037 also possesses the ability of paraben-transesterification. Alcohols compete with water molecules for the active center of enzymes, accelerating the transesterification of parabens and inhibiting hydrolysis. Considering that the fate of the transesterification product is still hydrolysis, we speculated and proved that such a “superfluous” mechanism is a detoxification strategy, and could be used in the bioremediation of parabens in wastewater. Microbial transesterification of parabens has been reported worldwide, and we speculated that it might be a common detoxification choice in the evolution of microorganisms worldwide.
研究领域:
微生物学
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环境科学
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生物化学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2025
·Vol. 142
·期 17
·e56781
·
IF 2.8
Yanru Chen,Linbo Wu
2,2,4,4-Tetramethyl-1,3-cyclobutanediol (CBDO) based copolyesters like poly(cyclohexane dimethylene-co-2,2,4,4-tetramethyl cyclobutylene terephthalate) (PCcBT) has high transparency, heat-resistance and safety and has been commercialized to replace bisphenol A polycarbonate in food contact applications. However, its synthesis and processing suffer from CBDO sublimation, composition deviation and relatively poor thermal stability. In order to obtain transparent heat-resistant CBDO-based copolyesters with improved synthesis robustness and thermal stability, poly(ethylene co-tetramethyl cyclobutene terephthalate (PEcBT)) copolyesters were synthesized from ethylene glycol (EG), CBDO, and terephthalic acid (TPA) via direct esterification route, and the structure–property was studied. It is found that the presence of EG effectively inhibited the sublimation of CBDO, and the resulting PEcBT copolyesters had reasonably good thermal stability so that the melt polycondensation proceeded smoothly without serious foaming. PEcBT copolyesters with intrinsic viscosity ([η]) over 0.60 dL/g were successfully synthesized at copolymer composition ( ϕ cBT ) up to 67 mol%. A quantitative relationship between T g and its influence factors is established. The copolyesters with ϕ cBT of 48–62 mol% displayed T g of 126°C–144°C, flexible tensile behavior, satisfactory tensile properties and reasonably good impact performance. Ternary PEPecBT copolyesters were also synthesized using 1,5-pentanediol as another diol comonomer to improve toughness of the materials.
研究领域:
材料科学
·
高分子化学
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产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2019
·
IF 6.97
Zhe Dong,Zengshe Liu,Jie Shi,Hu Tang,Xia Xiang,Fenghong Huang,Mingming Zheng
A sustainable and efficient reaction system for enzymatic oil modification is imperative for the food industry. Given the interfacial activation effect of lipase, the sufficient oil–water interface is vital for excellent catalytic activity of lipase. In the present study, a Pickering emulsion reaction system was prepared through directly using reactants as the oil phase and stabilized by mesoporous carbon spheres (MCS) after immobilization of lipase AYS (Candida rugosa, lipase@MCS). Lipase@MCS worked as both the emulsifier and catalyst. Each droplet in the Pickering emulsion was regarded as a microreactor with the reactants in the oil phase, and the removal of the product H2O “pushed” the reaction forward. Taking advantage of the adequate oil–water interface for “lid” opening of lipase and rapid mass transfer in MCS, the Pickering emulsion exhibited excellent enzymatic activity toward phytosterol esterification and transesterification, achieving 95.0% conversion after 1.5 h and catalytic efficiency (CE) of 6.8 mmol g–1 h–1 under nonequilibrium conditions. It is the best performance reported currently with the shortest reaction time, minimal amount of catalyst, and the highest CE (19-fold higher than free lipase one-phase reaction system). Immobilization of lipase on the MCS not only endowed the lipase with exceptional recyclability but also afforded a shield to protect the enzyme from deactivation in a harsh environment, as evidenced by the thermotolerance and recycling test results. This paper paves the way to advancing progress in enzyme-immobilized Pickering emulsion as a sustainable and high-efficiency platform for biocatalysis application.
研究领域:
生物化学
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食品科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
MATERIALS RESEARCH INNOVATIONS
·
2014
·
IF 0.473
J. J. Du,Y. Zuo,Q. Zou,B. Sun,M. B. Zhou,L. M. Li,Y. Man,Y. B. Li
Sponge-like polyurethane (PU) and composite have recently attracted attention in biomedical field as scaffolds for bone repair or tissue engineering research. In this study, castor oil was transesterified with glycerol to increase its functional hydroxyl groups and improve the mechanical properties of the resulting composite scaffolds. The glyceride of castor oil (GCO) was used to copolymerise with isophorone diisocyanate to generate PU, meanwhile blending with hydroxyapatite (HA) powder to prepare porous HA/PU composite scaffolds. The HA/glyceride based PU (GCPU) scaffolds were compared with pristine castor oil (PCO) based PU scaffolds (PCPU) by investigating the physicochemical properties and cytocompatibility using Fourier transform infrared, X-ray diffraction, SEM, mechanical testing and methylthiazolyldiphenyl-tetrazolium bromide assay. The results showed that the number of hydroxyl groups of GCO was nearly twice as high as that of PCO, which enhanced efficiently the crosslinking density of PU matrix. The compressive strength of HA/GCPU scaffold with 40 wt-%HA was ∼4·6 MPa, much higher than that (0·058 MPa) of HA/PCPU scaffolds. The in vitro biological results demonstrated that both GCPU and HA/GCPU scaffolds exhibited desirable cytocompatibility. The novel synthetic route is highly effective for the preparation of HA/GCPU porous scaffolds, which have good prospect in the repair of bone defects or for bone tissue engineering.
研究领域:
生物材料学
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组织工程学
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）