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Unconventional Fluorescent and Multi-responsive Polyethyleneimine with LCST and UCST Behavior:Synthesis,Characterization and Biological Applications

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Chinese Journal of Polymer Science 2024年第6期42卷 826-837页

作者： Feng-Ming Yin Li-Li Wu Shu-Sheng Li Xiao-Na Pan Xiao-Li Zhu Xu-Bao Jiang xiang zheng kong College of Chemistry and Chemical Engineering University of JinanJinan250022China Shandong Institute for Product Quality Inspection Jinan250102China College of Chemical Engineering Tianjin UniversityTianjin300072China

Non-aromatic fluorescent and multi-responsive materials,exhibiting inherent fluorescence emission and controlled phase change,have garnered significant attention in recent ***,the underlying interaction between their fluorescent properties and phase transition remains *** this study,we synthesized a series of catalyst-free aza-Michael addition-based polyethyleneimine(RFPEI)materials by reacting polyethyleneimine(PEI)with N-isopropyl acrylamide(NIPAM).The resulting RFPEI was comprehensively characterized,and demonstrated dual-phase transition behavior(LCST and UCST)in water,which could be finely tuned by adjusting its composition or external factors such as ***,upon UV irradiation(365 nm),RFPEI exhibited strong fluorescence *** further investigated the effects of NIPAM grafting percentage to PEI,polymer concentration,and pH on the LCST/UCST and fluorescent properties of RFPEI aqueous ***,we showcased the great potential of RFPEI as a versatile tool for physiological cell imaging,trace detection,and controlled release of *** study presents a novel class of stimuli-responsive fluorescent materials with promising applications in the field of biomedicine.

关键词： Polyethyleneimine Multi-responsiveness Intrinsic fluorescence emission Cell imaging Controlled drug release

Fluorescence Behavior and Emission Mechanisms of Poly(ethylene succinamide)and Its Applications in Fe^(3+)Detection and Data Encryption

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高分子科学：英文版 2023年第1期41卷 129-142页

作者： Xubao Jiang Qinghui Wang Bin Li Shusheng Li xiang zheng kong College of Chemistry and Chemical Engineering University of JinanJinan250022China Québec Center for Functional Materials Department of ChemistryUniversitéde SherbrookeSherbrookeQCJ1K2R1Canada

Conventional fluorescent polymers are featured by large conjugation *** contrast,a new class of fluorescent polymers without any conjugations is gaining great interest in immerging *** is a typical member of the conjugation-free fluorescent ***,studies on their electrophotonic property are hardly available,although widely used in many ***,poly(ethylene succinamide),PA24,is synthesized;its chemical structure confirmed through multiple techniques(NMR,FTIR,XRD,etc.).PA24 is highly emissive as solid and in its solution at room temperature,and the emission is excitation and concentration dependant,with an unusual blue shift under excitation from 270 nm to 320 nm,a hardly observed phenomenon for all fluorescent *** similar emission behavior is also observed under cryogenic condition at 77 *** emission behavior is thoroughly studied;the ephemeral emission blue-shift is interpreted through Förster resonance energy *** on its structures,the emission mechanism is ascribed to cluster-triggered emission,elucidated from multianalyses(NMR,FTIR,UV absorbance and DLS).In presence of a dozen of competitive metal ions,PA24 emission at 450 nm is selectively quenched by Fe^(3+).PA24 is used as probe for Fe^(3+)and H_(2)O_(2) detections and in data ***,this work provides a novel face of polyamide with great potential applications as sensors in different fields.

关键词： Polyamide Fluorescent emission Cluster formation Ferric ion detection Data encryption

NMR Analysis to Identify Biuret Groups in Common Polyureas

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Chinese Journal of Polymer Science 2018年第10期36卷 1150-1156页

作者： Wei-Guang Qiu Fei-Long Zhang Xu-Bao Jiang xiang-zheng kong College of Chemistry and Chemical Engineering University of Jinan

Polyureas （PU） are well known as a class of high impact engineering materials, and widely used also in emerging advanced applications. As a general observation, most of them are only soluble in a very limited number of highly protonic solvents, which makes their chemical structure analysis a great challenge. Besides the presence of abundant hydrogen bonding, the poor solubility of PU in common organic solvents is often ascribed to the formation of biuret crosslinking in their molecular chains. To clarify the presence of biuret groups in PU has been of great interest. To this end, two samples, based on hexamethylene diisocyanate （HDI） and toluene diisocyanate （TDI） respectively, were synthesized by precipitation polymerization of each of these diisocyanates in water-acetone at 30℃. Their chemical structures were analyzed by high resolution magic angle spinning （HR-MAS） NMR, and through comparison of their NMR spectra with those of specially prepared biuret-containing polyurea oligomers, it was concluded that biuret group was absent in all the PU prepared at 30 ℃. In addition, this NMR analysis was also applied to a PU obtained by copolymerization of TDI with ethylene diamine （EDA） and water at 65 ℃ in EDA aqueous solution. It was confirmed that biuret unit was also absent in this PU and that EDA was more active than water towards TDI. The presence of EDA was crucial to the formation of uniform PU microspheres. This study provides therefore a reliable method for the analysis of PU chemical structure.

关键词： Diisocyanate Polyurea Chemical structure Biuret NMR spectroscopy

Effects of cosolvent on formation and morphology of microspheres in precipitation polymerization of divinylbenzene in supercritical carbon dioxide

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Chinese Chemical Letters 2011年第4期22卷 489-492页

作者： Chun Sheng LiJing Cui Liang Xiao Li Zhu xiang zheng kong Key Laboratory of Fluorine Chemistry and Chemical Materials of Shandong Province College of Chemistry and Chemical Engineering University of Jinan Jinan 250022 China

Precipitation polymerizations of divinylbenzene（DVB） in pure supercritical carbon dioxide,and parallel runs with presence of a cosolvent were carried *** results showed that use of acetone as the cosolvent contributed greatly to the formation of the monodisperse *** microspheres,with obviously higher uniformity than reported up to date,were achieved using 6-7 mL of acetone in a reactor of 50 mL with DVB concentration of 0.4 mol/L under 16 MPa,a much lower pressure than previously reported without use of cosolvent.

关键词： Polydivinylbenzene microspheres Precipitation polymerization Supercritical carbon dioxide Cosolvent

A novel associative latex thickener using ethoxylated behenyl methacrylate as functional monomer

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Chinese Chemical Letters 2010年第5期21卷 616-619页

作者： xiang zheng kong Chen Wang Xu Bao Jiang Xiao Li Zhu College of Chemistry and Chemical Engineering University of JinanJinan 250022China

Alkali-soluble associative latex thickeners modified with hydrophobic long chain alkyl groups were prepared using common acrylics and varying amount of a functional monomer,ethoxylated behenyl methacrylate(BEM),through emulsion *** was found that the size of the emulsion particle became larger with addition of *** light transmittance of the thickener latex sharply increased with pH varied from 6 to *** associative latex thickener manifested a higher viscosity when solids in the latex thickeners were kept at 0.5 wt%or higher,and the optimal amount of BEM was found to be around 2.5 wt%,or 0.16 mol%.All thickener latexes modified with BEM have better shearing resistance than the BEM-free thickener.

关键词： Associative thickener Functional monomer Ethoxylated behenyl methacrylate Viscosity

Characterization and photocatalytic properties of silver and silver chloride doped TiO_2 hollow nanoparticles

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Chinese Chemical Letters 2012年第12期23卷 1399-1402页

作者： Ping Li Ji xiang zheng kong Jin Gang Wang Xiao Li Zhu College of Chemistry and Chemical Engineering University of Jinan

Using polystyrene （PSt） particles as template, PSt/TiO2 composite particles with AgCl incorporation were prepared through hydrolysis of tetrabutyl titanate in the presence of AgNO3 and NaCl. AgCl doped TiO2 hollow particles were successfully prepared with the PSt/TiO2 composite microspheres pretreated at 180 ℃ followed by calcination. The morphology of PSt/TiO2 particles and the crystal structures of the AgCl doped TiO2 hollow particles were characterized. The photocatalytic activity of the doped TiO2 hollow particles in degradation of Rhodamine B was tested under UV and visible lights and compared to that with Ag doped TiO2 particles. The results showed that TiO2 hollow particles, either doped with Ag or AgCl, demonstrated higher photocatalytic activity than the pure TiO2 particles. This enhancement in photocatalytic activity was more significant with AgCl doped TiO2 than that with Ag doped, and more distinct when the degradation was done under visible light than that under UV light.

关键词： TiO2 hollow particles AgCl doping Photocatalysis Light absorption shifting Rhodamine B degradation

Microencapsulation of dodecyl acetate by complex coacervation of whey protein with acacia gum and its release behavior

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Chinese Chemical Letters 2012年第7期23卷 847-850页

作者： You Tong Yu Li Na Liu Xiao Li Zhu xiang zheng kong College of Chemistry and Chemical Engineering University of JinanJinan 250022China

Complex coacervation of whey protein（WP） with acacia gum（AG） was carried out in water with the presence of dodecyl acetate （DA）,a component of insect sex pheromones,in order to obtain microcapsules with DA as the core material and WP-AG coacervate as the wall *** variations in wall/core ratios,concentrations of the wall materials in capsule preparations,DA encapsulation was optimized,which showed a high DA encapsulation was achieved when coacervation was conducted at pH 3.5 with wall/core mass ratio at 3 combined with concentration of wall materials at 1.0 wt%.Morphology and the structure of DA loaded microcapsules were examined by scanning electron microscope,which showed the microcapsules were of core/shell structure with DA encapsulated in the inner of the *** release was examined and the behavior of the release was discussed.

关键词： Whey protein Acacia gum Complex coacervation Insect pheromone encapsulation Controlled release

A novel and simple pathway to synthesis of porous polyurea absorbent and its tests on dye adsorption and desorption

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Chinese Chemical Letters 2013年第4期24卷 287-290页

作者： Shu-Sheng Li xiang-zheng kong Xu-Bao Jiang Xiao-Li Zhu College of Chemistry and Chemical Engineering University of Jinan

A novel one-step protocol for the preparation of porous polyurea material （PPU） through precipitation polymerization of toluene diisocynate （TDI） is presented. The process is based on step polymerization of one single monomer, TDI, with water in water-acetone mixed solvent. PPU is obtained without need for any porogen or additives, and no any chemical modification on the outcome polymer is necessary. The morphology, pore size and size distribution of PPU are characterized by scanning electron microscope and BET nitrogen adsorption. Taking acid fuchsine （AF） and Congo Red as dye examples in wastewaters, their adsorption on, desorption from PPU and the reusability of PPU were tested. Experimental conditions for AF adsorption were optimized with regard to pH, adsorption time, AF concentration and amount of PPU. Results demonstrate that the as-prepared PPU is of high performance in dyes adsorption and recycled use. This work presents therefore a novel and attractive candidate for removal of anionic dyes from wastewaters.

关键词： Precipitation polymerizationPorous polyureaDye removalIsothermal adsorption

A facile preparation and electrochemical properties of nickel based compound-graphene sheet composites for supercapacitors

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Chinese Chemical Letters 2015年第5期26卷 522-528页

作者： Li-Bin Zhang Sheng-Rong Yang Jin-Qing Wang Ye Xu xiang-zheng kong State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of Sciences Graduate University of Chinese Academy of Sciences College of Chemistry and Chemical Engineering University of Jinan

Composites of a nickel based compound incorporated with graphene sheets （NiBC-GS） are prepared by a simple flocculation, using hydrazine hydrate as flocculant and reductant, from a homogeneous intermixture of nickel dichloride and graphene oxide dispersed in N,N-dimethylformamide. Morphology, microstructure and thermal stability of the obtained products were characterized by field-emission scanning electron microscopy, X-ray diffraction and thermal gravimetric analysis. Furthermore, the electrochemical properties of NiBC-GS, as electrode materials for supercapacitors, were studied by cyclic voltammetry and galvanostatic charge]discharge in 2 mol L 1 KOH solution. It was determined that for NiBC-GS annealed at 250 ~C, a high specific capacitance of 2394 F g 1 was achieved at a current density of 1 A g^-1, with 78% of the value （i.e., 1864 F g^-1） retained after 5000 times of repeated galvanostatic charge/discharge cycling. The high specific capacitance and available charge/discharge stability indicate the synthesized NiBC-GS250 composite is a good candidate as a novel electrode material for supercapacitors.

关键词： Nickel based compound Graphene Electrochemical performance Supercapacitors