查找使用阿拉丁产品的科研文献

Effect of Sodium Salicylate on Improving the Lubricating Properties of [C18imC9]Br Wormlike Micelles in Glycerol/Propylene Glycol at Low Temperatures

Yimin Hu,Jing Sun,Zixian Cai,Meiling Lei,Yu Chen,Shaoan Lei,Huijiao Cao,Xia Guo

The formation of long cylindrical wormlike micelles at low temperatures (near 0 °C) is relatively rare. In this work, the effect of different salts on the viscoelasticity of the formed wormlike micelles by the ionic liquid surfactant (1-octadecyl-3-nonyl imidazolium bromide, [C18imC9]Br) and glycerol/1,2-propanediol mixture at low temperature was studied. The rheological measurements revealed that only sodium salicylate (NaSal) can increase the viscoelasticity of [C18imC9]Br wormlike micelles by up to 15 times and the existence of temperature range. When the [C18imC9]Br concentration is fixed, the viscoelasticity of the [C18imC9]Br/NaSal wormlike micelles increases and then decreases with the increase of NaSal concentration. Tribological results show that the [C18imC9]Br/NaSal wormlike micelles have excellent friction reduction and antiwear properties for steel/steel contact at 6.00 °C. The friction coefficient and wear volume of [C18imC9]Br/NaSal wormlike micelles first decrease and then increase with the increase of the NaSal concentration. In addition, their tribological properties are significantly better than those of pure [C18imC9]Br wormlike micelles under the same conditions. The lubrication effect of [C18imC9]Br/NaSal wormlike micelles at low temperatures is improved due to the adhesion of [C18imC9]Br/NaSal wormlike micelles and the protective film formed by the tribochemical reaction.

Folic acid-functionalized drug delivery platform of resveratrol based on Pluronic 127/D-α-tocopheryl polyethylene glycol 1000 succinate mixed micelles

Jifu Hao,Tiantian Tong,Kai Jin,Qiannan Zhuang,Te Han,Yanping Bi,Jianzhu Wang,Xiaodan Wang

A folic acid (FA)-functionalized drug vehicle platform based on Pluronic 127 (P127)/D-α-tocopheryl polyethylene glycol 1000 succinate (TPGS) mixed micelles was orchestrated for an effective delivery of the model drug resveratrol in order to address the problem of poor water solubility and rapid metabolism of resveratrol and improve its targeted accumulation at tumor site. The FA-decorated mixed micelles were prepared using thin-film hydration method and optimized by central composite design approach. The micelles were also characterized in terms of size and morphology, drug entrapment efficiency and in vitro release profile. In addition, the cytotoxicity and cell uptake of the micelles were evaluated in folate receptor-overexpressing MCF-7 cell line. In vivo pharmacokinetic and biodistribution studies were also performed. The average size of the micelles was ~20 nm with a spherical shape and high encapsulation efficiency (99.67%). The results of fluorescence microscopy confirmed the targeting capability of FA-conjugated micelles in MCF-7 cells. FA-modified micelles exhibited superior pharmacokinetics in comparison with that of solution. Further, the low accumulation of resveratrol-loaded FA micelles formulation in the heart and kidney avoided toxicity of these vital organs. It could be concluded that folate-modified P127/TPGS mixed micelles might serve as a potential delivery platform for resveratrol.

Microstructurally tunable pickering emulsions stabilized by poly(ethylene glycol)-b-poly(ε-caprolactone) diblock biodegradable copolymer micelles with predesigned polymer architecture

Chao Lin,Pengju Pan,Guorong Shan,Miao Du

Poly(ethylene glycol)- b -poly( ε -caprolactone) diblock copolymers ( PEG- b -PCL) with predesigned hydrophilic/hydrophobic block length ratios have been synthesized and self-assembled to form micelles, then used to emulsify medium-chain triglycerides with an aqueous phase. The morphologies and sizes of PEG- b -PCL copolymer micelles have been characterized by transmission electron microscopy and dynamic light scattering. Interfacial tension testing between micellar dispersions and oil, combined with water contact angle measurements, have been performed to assess the ability of these micelles to adjust interfacial tension and micellar hydrophobicity, respectively. Relationship between the wettability of PEG- b -PCL copolymer micelles and their emulsification properties has been proved through phase diagram, optical microscopic observation, droplet sizes evolution and phase separation behavior of Pickering emulsion samples. Results show that both oil-in-water and water-in-oil Pickering emulsions, as well as water-in-oil-in-water (W/O/W) double-Pickering emulsions, may be controllably prepared through one-step homogenization. Double microstructure of W/O/W Pickering emulsion has proved to be extremely stable during long-term storage.

A photo-degradable injectable self-healing hydrogel based on star poly(ethylene glycol)-b-polypeptide as a potential pharmaceuticals delivery carrier

Dinglei Zhao,Quan Tang,Qiang Zhou,Kang Peng,Haiyang Yang,Xingyuan Zhang

As one of the most promising biomaterials, injectable self-healing hydrogels have found broad applications in a number of fields such as local drug delivery. However, controlled release of drugs in hydrogels is still difficult to realize up to now. Here, we report a novel photo-degradable injectable self-healing hydrogel based on the hydrophobic interaction of a biocompatible four-arms star polymer, poly(ethylene glycol)-b-poly(γ-o-nitrobenzyl-L-glutamate). The hydrophobic interaction between poly(γ-o-nitrobenzyl-L-glutamate) not only connects poly(ethylene glycol)-b-poly(γ-o-nitrobenzyl-L-glutamate) together with a crosslink but also provides a hydrophobic domain to encapsulate hydrophobic pharmaceuticals such as doxorubicin (DOX). Due to the dynamic character of the hydrophobic interaction, the hydrogel exhibits excellent injectable and self-healing ability. In particular, the photolabile o-nitribenzyl ester group is cleaved under UV irradiation. As a result, the hydrophobic domain transforms into the hydrophilic one and the embedded DOX is released effectively. An increasing release ratio of DOX dramatically enhances the apoptosis ratio of HeLa cells. We expect these attractive properties may be beneficial to practical applications of the hydrogel as an effective local drug delivery means in a truly physiological environment.

A Dual-sensitive Hydrogel Based on Poly(Lactide-co-Glycolide)-Polyethylene Glycol-Poly(Lactide-co-Glycolide) Block Copolymers for 3D Printing

Yang Zhou,Yuecheng Cui,Li-Qun Wang

The thermo-sensitive hydrogel formed by triblock copolymers of polyethylene glycols and aliphatic polyesters serves as a promising candidate for bioink due to its excellent biodegradability and biocompatibility. However, the thermo-crosslinking alone cannot achieve a robust hydrogel to support the 3D printed constructs without collapse. Herein, a photo-crosslinkable group was introduced into the triblock copolymers to achieve a dual-sensitive hydrogel. A triblock copolymer poly(lactide-co-glycolide)-polyethylene glycol-poly(lactide-co-glycolide) decorated with acrylate group in the chain end was prepared. The obtained aqueous solutions of the copolymers could transform into hydrogels with excellent shear thinning properties and rapid elastic recovery properties spontaneously on the increase of temperature. The resulted thermogels also allowed for photo-crosslinking by exposure to ultraviolet radiation, with storage modulus dramatically increased to stable the printed constructs. Through a two-step crosslinking strategy, complicated tissue-like constructs with high shape fidelity can be printed using the dual-sensitive inks. Moreover, the mechanical strength, swelling ratio, and printability of the hydrogels can be tuned by varying the substitution rate of the acrylate group without compromising the inks’ extrudability. We expect that the dual-sensitive hydrogels may be used as bioinks to print large constructs for applications in tissue engineering.

Idarubicin-loaded methoxy poly(ethylene glycol)-b-poly(l-lactide-co-glycolide) nanoparticles for enhancing cellular uptake and promoting antileukemia activity

Bin Liang,Na Li,Shuofei Zhang,Aihua Qi,Jianhua Feng,Weiwei Jing,Changcan Shi,Zhaipu Ma,Shenmeng Gao

Hydrogen-bond engineering of polyethylene glycol/aramid nanofiber separators via phase transition for high-safety and high-energy lithium-sulfur batteries

Guanhao Qi,Jiahao Ma,Chengye Mao,Yanan Sun,Zhenli Li,Yang Hao,Shanshan Gao,Xiaoming Song,Fushan Chen

High performance and safety are essential prerequisites for the large-scale application of future energy storage systems. Lithium-sulfur (Li-S) batteries have garnered significant attention from the scientific community due to their high energy density and cost-effectiveness. However, challenges such as the polysulfide shuttle effect, thermal instability of commercial separators, and insufficient mechanical strength continue to hinder the commercialization of Li-S batteries. This paper presents a fabrication process for a hydrogen-bond-based polyethylene glycol (PEG)-modified aramid nanofiber (ANF) composite separator (PEG/ANF separator). The inherent properties of aramid nanofibers combined with PEG's unique flexible ether chain structure endow this separator with exceptional thermal stability (no dimensional shrinkage even at 200 °C), while also suppressing polysulfide shuttle effects and lithium dendrite growth. Results demonstrate that the PEG/ANFs separator exhibits an initial discharge specific capacity of up to 876.6 mAh·g −1 and maintains an average coulombic efficiency of 99.575 % after 300 cycles at 0.1C. This approach provides a scalable solution for designing highly safe and reliable energy storage devices.

Smart control of cotton fabric comfort by cross-linking thermo-responsive poly(2-(2-methoxyethoxy) ethoxyethyl methacrylate-co-ethylene glycol methacrylate)

Yangyi Chen,Jie An,Qi Zhong,Peter Müller-Buschbaum,Jiping Wang

The smart control of cotton fabric comfort by cross-linking thermo-responsive random copolymer is investigated. The monomers 2-(2-methoxyethoxy) ethoxyethyl methacrylate (MEO2MA) and ethylene glycol methacrylate (EGMA) with a molar ratio of 17:3 are selected to synthesize the thermo-responsive random copolymer poly(2-(2-methoxyethoxy) ethoxyethyl methacrylate-co-ethylene glycol methacrylate), abbreviated as P(MEO2MA-co-EGMA). By using citric acid as a cross-linking agent, the obtained P(MEO2MA-co-EGMA) is successfully immobilized onto cotton fabrics. Smart control is achieved from the thermo-responsive behavior of the copolymer. Cross-linked P(MEO2MA-co-EGMA) will collapse when the ambient temperature exceeds its transition temperature. Therefore, the formerly compact P(MEO2MA-co-EGMA) layer will switch to a porous structure, and the air/moisture permeability of the textiles is enhanced. As the comfort of the textiles is closely related to the air/moisture permeability, a smart control of the cotton fabric comfort can be realized. In addition, the softness of cotton fabrics with and without thermo-responsive polymers does not show a prominent change, even when the applied solution concentration is as high as 16% (wt%). On the contrary, the stiffness of the cotton fabric coated with poly(N-isopropylacrylamide) (PNIPAM) is significantly higher than the original cotton fabric, indicating that homo PNIPAM is less suitable for textiles used in daily lives. Moreover, the whiteness and mechanical properties are studied and stay unchanged after cross-linking. As a consequence, the introduction of P(MEO2MA-co-EGMA) into textiles can provide textiles with smart control of cotton comfort, and it will not influence the wearabilities of the textiles.

Simultaneous Extraction of Both Basic and Non-basic N-Compounds from Oil via Triethylene Glycol–Metal Complex Solvent: Performance and Behavior

Yafen Dai,Linzi Shi,Dan Liu,Xiaolei Li,Hanlin Cheng,Kezhuo Zhang,Jiajun Gao

Simultaneous extraction of basic and non-basic N-compounds from oil is still a big challenge. Triethylene glycol (TEG) encounters very weak Brønsted acidity. Its N-distribution coefficient [DN, (mmol·gEx–1)/(mmol·gOil–1)] for the basic was below 7.0. In this work, metals dissolved in TEG can improve the Lewis acidity of the extractant and bring about the simultaneous removal. For example, DN of TEG–Ag(I) can increase to 40.5 for quinoline and 57.9 for pyridine, respectively. For the non-basic, it still remained higher than 70.0. The promoted performance was ascribed to the improvement of extractive behavior of the basic. From TEG to TEG–Ag(I), first, the distribution of equilibrium N-concentrations between two phases was significantly changed from the straight line to the non-linear curve with the plateau. Second, the interaction type inside the system was optimized. The Ag(I)-based complexation coupled with the TEG-based H-bonding was identified. Third, the interaction intensity was increased as well. Ag(I) contributed much to reduction of Gibbs free energy change for the basic. Therefore, enhancing Lewis acidity of the extractant was a feasible way for the extraction of the N-compounds.

Bio-based poly(butylene 2,5-furandicarboxylate)-b-poly(ethylene glycol) copolymers with adjustable degradation rate and mechanical properties: Synthesis and characterization

Han Hu,Ruoyu Zhang,Andreia Sousa,Yu Long,Wu Bin Ying,Jinggang Wang,Jin Zhu

Bio-based poly(butylene furandicarboxylate)-b-poly(ethylene glycol) copolymers are successfully synthesized through transesterification and melt polycondensation. The resulted polymers are characterized in terms of structural, thermal and mechanical properties. In addition, for the first time relevant hydrolytic degradation studies for the copolymers applications are systematically conducted in neutral and alkaline conditions. The PEG weight fraction ranges from 10% to 60%, as determined by 1 H NMR. Isothermal crystallization tests show that the copolymers own faster crystallization rate than that of PBF, with melting temperature higher than 120 °C. Water contact angle and water uptake characterizations show that the introduction of increasing amounts of PEG improves the hydrophilic character of the copolymers. Tensile tests clearly indicate that elongation at break drastically increase with PEG content, up to 5 times compared to PBF. From the Notched Izod impact tests, most samples are unbroken in the impact testing, showing excellent impact toughness. It is surprising to find that after water uptake, the PBF-PEGs still have acceptable mechanical properties. The weight loss during hydrolytic degradation is significant after 5 weeks for most of copolymers. With fast hydrolytic degradation rate and good mechanical properties, these copolymers own potential applications in areas like biomedical industry.

Preparation of Poly (Vinylimidazole-Co-Polyethylene Glycol Diacrylate) Cryogel and Its Application for Simultaneous Heavy Metal Removal and Oil–Water Separation

Hou Wangxu,Ma Feng,Li Junying,Tian Haoran,Chen Guangxu,Li Guixin,Jing Liling,Yang Pengfei

The environmental pollution caused by complicated wastewater, such as oily wastewater with various metal ions, is becoming more and more serious, which promotes the rapid development of separation materials and relevant methods. In this paper, poly (vinylimidazole-co-polyethylene glycol diacrylate) (V-co-P) cryogel was synthesized by poly (ethylene glycol) diacrylate and vinylimidazole as monomers via freeze-thawing method, followed by its characterization with SEM, FT-IR, and XPS. It was found that Cu(II) was chemically absorbed on poly (V-co-P) cryogels and the maximum adsorption capacity of the poly (V-co-P) cryogel was determined to be 51.57 mg g −1 . More importantly, the poly (V-co-P) cryogel can effectively separate various oil-in-water emulsions containing Cu(II) in one step, and the micron droplets in the emulsion disappeared completely. The efficiency of Cu(II) removal was determined to be more than 97.5%. Moreover, this cryogel could be reused without significant loss of separation performance after ten cycles. In general, the cryogel prepared by simple freezing polymerization shows both heavy metal removal capacity and oil–water separation ability, which offers considerable potential applications on the disposal of complicated wastewater in the environment.

A Conductive, Self-Healing Hybrid Hydrogel with Excellent Water-Retention and Thermal Stability by Introducing Ethylene Glycol as a Crystallization Inhibitor

Yiming Zhao,Yonggan Yan,Xin Cui,Xunwei Wu,Hui Wang,Jun Huang,Xiaoyong Qiu

The rapid development of flexible electronics motivates the design and synthesis of stable hydrogels that possess good stretchability and conductivity under harsh environment. The long-term durability of traditional hydrogels generally fails at high temperatures. In this work, a high-temperature-tolerant, self-healable hybrid hydrogel showing excellent water-locking and adhesive properties was developed through ultraviolet curing of acrylamide (AM) and hyper-branched polyethyleneimine (PEI) in highly salted ethylene glycol-water solution. Ethylene glycol was used as a crystallization inhibitor and greatly enhanced the solubility of sodium acetate (NaAc). The fabricated hydrogel can retain 75 % of its initial weight for 9 hours at 100 °C or 88 % of its initial weight for 77 hours at 15 % relative humidity (RH) environment. The dehydrated gel was flexible (tensile strain > 1700 %) and conductive after storing at high temperatures (e.g. 100 °C) for a long term. Moreover, the highly salted hydrogel showed remarkable water adsorbing ability in the air: it can recover to its original weight after losing water at high temperature or low humidity conditions. In addition, the separated hydrogel fragments could heal into a single piece in 30 s, and the hydrogel showed reversible adhesiveness to both organic (6.2 kPa for pigskin, 28 kPa for wood) and inorganic (111.9 kPa for glass, 135.5 kPa for iron) substances for at least 5 cycles. This work provides a facile way of obtaining multi-functional conductive hydrogels that can work at high temperatures, demonstrating long-term prospects in engineering applications.