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Polyolefin containing multi-block polymers and upcycling of mixed plastics

science China chemistry 2025年第6期68卷 2589-2594页

作者： Wu Li Daohong Liao Yougui Li Guifu Si Changle Chen School of Chemistry and Chemical Engineering Hefei University of Technology Key Laboratory of Precision and Intelligent Chemistry Department of Polymer Science and Engineering University of Science and Technology of China

A significant challenge in the recycling of plastics is the separation of various polymers. Mechanical recycling represents one of the most straightforward and cost-effective approaches to mitigate the escalating issue of plastic pollution. Unfortunately, the inevitable presence of mixed plastics in the waste stream and their phase separation always result in suboptimal properties for mechanically recycled materials. Multi-block copolymers(MBCPs) compatibilization represents an efficient strategy to address this issue and for upcycling of mixed plastics. The key to the implementation of this strategy lies in the efficient syntheses and structural modifications of diverse MBCPs. Especially, very few synthetic routes have been reported for the synthesis of MBCPs containing polyolefin blocks. In this contribution, we present a cyclic-acyclic monomers metathesis polymerization(CAMMP)mediated strategy for the preparation of polyolefin containing MBCPs using commercially available or easily accessible telechelic diol polymers. These polyolefins containing MBCPs can efficiently serve as compatibilizer additives for the upcycling of mixtures of polyolefins and other plastics. The combination of great variety of telechelic diol polymers with the ease of microstructure modification during CAMMP synthesis makes this strategy attractive for future investigations and potential practical applications.

关键词： polyolefin polymer synthesis copolymer upcycling compatibilization

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Polyelectrolyte Complexes and Coacervates Formed by De novo-Designed Peptides and Oligonucleotide

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Chinese Journal of polymer science 2024年第9期42卷 1333-1340,I0007页

作者： Tian-Hao Ren De-Hai Liang Beijing National Laboratory for Molecular Sciences Department of Polymer Science and Engineering and the Key Laboratory of Polymer Chemistry and Physics of the Ministry of EducationCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing100871China

The liquid-liquid phase separation of biopolymers in living cells contains multiple interactions and occurs in a dynamic *** the regulation mechanism is still a *** this work,we designed a series of peptides(XXLY)_(6)SSSGSS and studied their complexation and coacervation behavior with single-stranded ***“X”and“Y”are varied to combine known amounts of charged and non-charged amino acids,together with the introduction of secondary structures and pH *** show that the electrostatic interaction,which is described as charge density,controls both the strength of complexation and the degree of chain relaxation,and thus determines the growth and size of the *** hydrophobic interaction is prominent when the charges are ***,the secondary structures of peptides exhibit profound effect on the morphology of the phases,such as solid phase to liquid phase *** study gains insight into the phase separation under physiological *** is also helpful to create coacervates with desirable structures and functions.

关键词： Polyelectrolyte complex Coacervate Peptides Secondary structure Electrostatic interaction

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Photoswitchable Spiropyridine Enabled Photoactuation of polymeric Hydrogels under Physiological pH Conditions

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Chinese Journal of polymer science 2024年第10期42卷 1602-1609,I0015页

作者： Cong Liao Meng-Qi Du Chuang Li Key Laboratory of Precision and Intelligent Chemistry Department of Polymer Science and EngineeringUniversity of Science and Technology of ChinaAnhui230026China

The incorporation of molecular switches into polymer networks has been a powerful approach for the development of functional polymer materials that display macroscopic actuation and function enabled directly by molecular ***,such materials sometimes require harsh conditions to perform their functions,and the design of new molecular photoswitches that can function under physiological conditions is highly ***,we report the design and synthesis of a spiropyridine-based photoswitchable hydrogel that exhibits light-driven actuation at physiological *** to its high p Ka,spiropyridine maintains its ring-open protonated form at neutral pH,and the resulting hydrogel remains in a swollen *** irradiation with visible light,the ring closure of spiropyridine leads to a decrease in the charge and a reduction in the volume of the *** contracted gel could spontaneously recover to its expanding state in the dark,and this process is highly dynamic and reversible when the light is switched on and ***,the hydrogel shows switchable fluorescence in response to visible *** deformation is observed in the hydrogel thin films upon irradiation from one ***,the independence of this spiropyridine hydrogel from the acidic environment makes it biotolerant and shows excellent *** biocompatible spiropyridine hydrogel might have important biorelated applications in the future.

关键词： Spiropyridine photowitch polymer hydrogel Photoactuation Physiological pH Biocompatibility

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Dual-functional poly(2-methyl-2-oxazoline)/poly(2-(dimethylamine)ethyl methacrylate)mixed brushes with switchable protein adsorption and antibacterial properties

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Chinese Journal of Chemical engineering 2024年第2期66卷 19-30页

作者： Kang He Liangyu Zhu Yanmei Wang CAS Key Laboratory of Soft Matter Chemistry Department of Polymer Science and EngineeringUniversity of Science and Technology of ChinaHefei 230026China

Herein,binary mixed brushes consisting of poly(2-methyl-2-oxazoline)(PMOXA)and poly(2-(dimethylamine)ethyl methacrylate)(PDMAEMA)with different chain lengths were fabricated by successive grafting of NH_(2)-terminated PMOXA and SH-terminated PDMAEMA onto polydopamine-anchored *** mixed-brush coating was characterized by variable-angle spectroscopic ellipsometry,X-ray photoelectron spectroscopy,Fourier transform infrared spectroscopy,zeta potential measurements,water contact angle,and atomic force *** mixed brushes showed tunable surface charge,wettability,and surface roughness,depending on the degree of PDMAEMA swelling under varying pH and ionic strength(Ⅰ).Then the adsorption behaviors of pepsin,bovine serum albumin(BSA),γ-globulin,and lysozyme,four very different proteins with regard to isoelectric point,on the mixed brushes coating were studied by using fluorescence microscopy and surface plasmon *** the chain length of PDMAEMA was about twice as long as PMOXA,the mixed brushes not only had high adsorption capacity for pepsin,BSA,and y-globulin but also had a desorption efficiency of 86.9%,87.1%,and 93.5%,*** is explained that electrostatic attraction between the protonated PDMAEMA and positively charged acidic proteins(pepsin and BSA,whose isoelectric points were below the pK_(a) of PDMAEMA)would drive the intensive adsorption(at pH 3,I=10^(-3)mol·L^(-1)for pepsin,and pH 5,I=10^(-5)mol·L^(-1)for BSA),while desorption was dominated by the hydrophilic PMOXA when PDMAEMA was shrinking(at pH 7,I=10^(-1)mol·L^(-1)for pepsin,and pH 9,I=10^(-1)mol·L^(-1)for BSA).Furthermore,the isoelectric precipitation led to the adsorption of neutral protein(γ-globulin,whose isoelectric point was near the pK_a of PDMAEMA)at pH 7,I=10^(-5)mol·L^(-1),while electrostatic repulsion and antifouling PMOXA triggered the desorption of y-globulin at pH 3,I-10^(-1)mol·L^(-1).However,alkaline protein(lysozyme,whose isoelectric point was higher than

关键词： Switchable conformation transition Controllable protein adsorption Mixed brushes Isoelectric point Antibacterial surface

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Synthesis of Sulfur/Selenium-containing Polyester with Recyclability and Controllable Hydrophilicity and Glass Transition Temperature

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Chinese Journal of polymer science 2023年第12期41卷 1836-1845,I0004,I0005页

作者： Wen-Jing Li Xiang-Qiang Pan Jian Zhu Zheng-Biao Zhang Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application Department of Polymer Science and EngineeringCollege of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhou 215123China

We present a ring-opening polymerization of bridged cyclic lactone utilizing alcohol as the initiator and organic base as the *** γ-butyrolactone monomers(PhSGBL and PhSeGBL)were synthesized efficiently from commercially available 3-cyclohexene-1-carboxylic *** to the ring strain of the bridged structure,ring-opening polymerization of this type of γ-butyrolactone derivative was successfully carried out under mild conditions,e.g.,using ethylene glycol as the initiator and a commercial catalyst[1,5,7-triazabicyclo[4.4.0 dec-5-ene(TBD)]]as the catalyst at 30℃.The obtained polymer could be degraded to its monomer for recycling in the presence of ZnCl_(2) as a *** and PhSeGBL could also be copolymerized with ε-caprolactone to tune the glass transition ***,the hydrophilicity of the obtained sulfur-containing polymers could be adjusted by selectively oxidizing the thioether side group to sulfone/sulfoxide,which offered a way to tune the hydrophilicity of *** the other hand,the obtained selenium-containing compound could be degraded in the presence of m-CPBA(3-chloroperbenzoic acid),which offered potential application in sustained drug release.

关键词： Ring-opening polymerization Polyester Closed-loop recycling Selective oxidation

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Novel photoresponsive dinuclear nickel catalysts for ethylene (co)polymerization

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science China chemistry 2025年第2期68卷 714-722页

作者： Chenlong Nan Tong Pang Jiaxing Zhao Lijia Fan Chen Zou Xin-Qi Hao Mao-Ping Song Jun-Fang Gong Changle Chen Hui Jiang College of Chemistry Pingyuan LaboratoryZhengzhou UniversityZhengzhou 450001China CAS Key Laboratory of Soft Matter Chemistry Department of Polymer Science and EngineeringUniversity of Science and Technology of ChinaHefei 230026China

Compared with the conventional strategies of electronic and/or steric perturbation,catalytic olefin polymerization modulated by light irradiation or metal-metal cooperativity effect is a fascinating challenge that attracts considerable attention in the academic *** this context,we design a strategy that could employ both effects to influence the polymerization *** dinuclear salicylaldimine andα-imino-ketone nickel complexes bearing a stiff-stilbene bridge were prepared,which could transfer between(E)-isomers and(Z)-isomers under ultraviolet *** isomerization can tune the electronic,steric and metal-metal cooperativity effects of the nickel *** this way,the catalytic activity,as well as polymer microstructures including molecular weight and branching density can be modulated in ethylene polymerization and copolymerization *** strategy is generally applicable to other olefin polymerization catalytic systems and other types of transition metal mediated catalysis.

关键词： photoresponsive dinuclear catalyst nickel(II) polar monomer olefin copolymerization

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Cyclic-acyclic monomers metathesis polymerization to access photodegradable polydicyclopentadiene and polyethylene-like materials

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science China chemistry 2024年第4期67卷 1311-1315页

作者： Wu Li Daohong Liao Yougui Li Guifu Si Changle Chen School of Chemistry and Chemical Engineering Hefei University of TechnologyHefei 230009China Key Laboratory of Precision and Intelligent Chemistry Department of Polymer Science and EngineeringUniversity of Science and Technology of ChinaHefei 230026China

The development of degradable and recyclable polymers is an attractive strategy to tackle the post-consumption pollution issue of commercial ***-acyclic monomers metathesis polymerization(CAMMP)has been recently reported to produce degradable thermoset,thermoplastic and elastomeric polymers,and their degradability is enabled with addition of various *** this contribution,we demonstrate that the utilization of diene comonomers containing photodegradable moiety can give access to thermoset and thermoplastic materials bearing photo-degradation *** copolymerization of a series easily accessible diene comonomers bearing photodegradable ortho-nitrobenzyl moieties with dicyclopentadiene(DCPD)or cyclooctene(COE)leads to the formation of photodegradable p DCPD thermosets and p COE thermoplastic polymers with mechanical properties comparable to their non-degradable *** importantly,their photo-degradation properties can be efficiently tuned with the addition of ultraviolet absorber during in-situ polymerization.

关键词： metathesis polymerization photodegradable polydicyclopentadiene polyethylene-like materials

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A Self-Healing Elastomer with Extremely High Toughness Achieved by Acylsemicarbazide Hydrogen Bonding and Cu^(2+)-Neocuproine Coordination Interactions

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Chinese Journal of polymer science 2024年第10期42卷 1425-1434,I0007页

作者： Xiao-Ming An Yi-Ping Wang Tang-Song Zhu Chong Xing Xu-Dong Jia Qiu-Hong Zhang Key Laboratory of High Performance Polymer Material and Technology of MOE Department of Polymer Science and EngineeringSchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing210093China State Key Laboratory of Coordination Chemistry Nanjing UniversityNanjing210093China

Elastomers with high mechanical toughness can guarantee their durability during service ***-healing ability,as well as recyclability,can also extend the life of materials and save the consuming cost of the *** efforts have been dedicated to promoting the mechanical toughness as well as the self-healing capability of elastomers at the same time,while it remains a challenge to balance the trade-off between the above properties in one *** we proposed a molecular design driven by dual interactions of acylsemicarbazide hydrogen bonding and Cu^(2+)-neocuproine coordination *** introducing the reversible multiple hydrogen bonds and strong coordination bonds,we successfully fabricated an extremely tough and self-healing *** elastomer can achieve an impressive top-notch toughness of 491 MJ/m^(3).Furthermore,it boasted rapid elastic restorability within 10 min and outstanding crack tolerance with high fracture energy(152.6kJ/m^(2)).Benefiting from the combination of dynamic interactions,the material was able to self-repair under 80℃conveniently and could be reprocessed to restore the exceptional mechanical properties.

关键词： Metal-ligand coordination Hydrogen bond Ultra-tough elastomer Self-healing

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Novel high-temperature thermochromic polydiacetylene material and its application as thermal indicator

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Chinese Chemical Letters 2024年第11期35卷 461-464页

作者： Zhiqing Ge Zuxiong Pan Shuo Yan Baoying Zhang Xiangyu Shen Mozhen Wang Xuewu Ge Key Laboratory of Precision and Intelligent Chemistry Department of Polymer Science and EngineeringUniversity of Science and Technology of ChinaHefei 230026China

The design and synthesis of organic high-temperature reversible thermochromic materials is one of the difficult issues in the field of organic chromic *** this paper,four diacetylene monomers named DBA-PCDA,TBA-PCDA,DBE-PCDA and TBE-PCDA,each containing multiple diacetylene units,were synthesized from 10,12-pentacosadiynoic acid(PCDA)through the amidation or esterification reactions,using 4,4'-diaminobiphenyl,1,3,5-tris(4-aminophenyl)benzene,4,4'-dihydroxybiphenyl,and 1,3,5-tris(4-hydroxyphenyl)benzene as bridging *** effects of functional groups that can form hydrogen bond andπ-πinteractions on the solid-state polymerization properties of monomers and the thermochromic properties of the corresponding PDAs were *** results show that only DBA-PCDA and TBAPCDA,which contain functional groups that can form hydrogen bonding interactions,can be polymerized under 254-nm UV *** corresponding poly(DBA-PCDA)exhibits reversible thermochromic property even heated up to 200℃,showing a potential application in the field of high-temperature thermal indicator above 100℃.This work provides a new perspective to the development of PDA with high-temperature reversible thermochromic property.

关键词： Polydiacetylene High-temperature thermochromism Melting behavior π-πinteractions

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The effect of chemically modified expandable graphite on flame-retardant properties of waterborne intumescent flame-retardant coating

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Journal of Industrial and engineering chemistry 2025年 149卷 366-373页

作者： Kim, Tae Young Park, Jin Hwan Kim, Oh Young Hwang, Seok-Ho Materials Chemistry & Engineering Laboratory Department of Polymer Science & Engineering Dankook University Gyeonggi-do Yongin16890 Korea Republic of

In this study, a modified expandable graphite material (mEG) with enhanced hydrophilic properties was successfully prepared with a natural graphite as the main raw material and polymeric 4,4′‐methylene diphenyl isocyanate (pMDI) as an interlinking agent, and polyethylene glycol (PEG) as surface modifier. X-ray diffraction (XRD) and volume expansion analyses verified the anion intercalation that produced the expandable graphite (EG). And the results of X-ray photoelectron spectroscopy (XPS) and thermogravimetric analysis (TGA) raveled that 6.9% of PEG was chemically anchored on the expandable graphite (EG) surface. The contact angle of mEG was 39.6°, indicating that the surface is more hydrophilic than that of the EG surface (79.7°). The intumescent flame-retardant (IFR) coatings exhibited a more satisfactory flame-retardant effect when a mEG was added into the acryl resin matrix because of the synergistic effect of the dispersibility of mEG in the acryl resin matrix, resulted in the limited oxygen index (LOI) from 23 to 26%. Moreover, the total heat release (THR) of the IFR coating with mEG significantly decreased compared with that of the pure coating. The enhanced flame retardancy was due to the well-dispersed mEG in the acryl resin matrix, which may cause continuous carbon layer in the later stages of combustion. © 2025

关键词： X ray photoelectron spectroscopy

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