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A universal strategy for achieving dual cross-linked networks to obtain ultralong polymeric room temperature phosphorescence

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Science China Chemistry 2023年第4期66卷 1161-1168页

作者： Yifan Niu Yan Guan Chunye Long Chaofan Ren Jiwen Lu Chanjuan Jin Ping Wang Xinghe Fan He-Lou Xie Key Laboratory of Environment-friendly Chemistry and Application of Ministry of Education Key Laboratory of Polymeric Materials and Application Technology of Hunan Province and Key Laboratory of Advanced Functional Polymer Materials of Colleges and Universities of Hunan ProvinceCollege of ChemistryXiangtan UniversityXiangtan 411105China Beijing National Laboratory for Molecular Sciences Key Laboratory of Polymer Chemistry and Physics of Ministry of EducationCenter for Soft Matter Science and EngineeringCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China

Efficient polymeric room-temperature phosphorescence(PRTP)with excellent processability and flexibility is highly desirable but still faces formidable challenge.Herein,a general strategy is developed for efficient PRTP through photo-polymerization of phosphor monomers and N-isopropylacrylamide(NIPAM)spontaneously without a crosslinker.Remarkably ultralong lifetime of 3.54 s with afterglow duration time of 25 s and decent phosphorescent quantum efficiency of 13%are achieved.This efficient PRTP has been demonstrated to be derived from the synergistic effect of the covalent and hydrogen bonds networks formed through photo-polymerization of NIPAM.The electron paramagnetic resonance(EPR)spectra confirmed that methyl radicals are generated under the irradiation of ultraviolet light and promote the formation of covalent cross-linking networks.This strategy has also been proved to be generalizable to several other phosphor monomers.Interestingly,the polymer films display ultrahigh temperature resistance with long afterglows even at 140℃ and unexampled ultralong lifetime of 2.45 s in aqueous solutions.This work provides a simple and feasible avenue to obtain efficient PRTP.

关键词： universal strategy ultralong polymeric room temperature phosphorescence dual cross-linked networks photopolymerization crosslinker

The role of galectin-4 in physiology and diseases

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Protein & Cell 2016年第5期7卷 314-324页

作者： Zhan-Qi Cao Xiu-Li Guo Department of Pharmacology School of Pharmaceutical Sciences Shandong University Jinan 50012 China

Galectin-4, a tandem repeat member of the β-galactoside-binding proteins, possesses two carbohydraterecognition domains （CRD） in a single peptide chain. This lectin is mostly expressed in epithelial cells of the intestinal tract and secreted to the extracellular. The two domains have 40% similarity in amino acid sequence, but distinctly binding to various ligands. Just because the two domains bind to different ligands simultaneously, galectin-4 can be a crosslinker and crucial regulator in a large number of biological processes. Recent evidence shows that galectin-4 plays an important role in lipid raft stabilization, protein apical trafficking, cell adhesion, wound healing, intestinal inflammation, tumor progression, etc. This article reviews the physiological and pathological features of galectin-4 and its important role in such processes.

关键词： galectin-4 lipid raft crosslinker intestinalinflammation tumor progression

Improved method for synthesis of low molecular weight protamine–siRNA conjugate

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Acta Pharmaceutica Sinica B 2018年第1期8卷 116-126页

作者： Zhili Yu Junxiao Ye Xing Pei Lu Sun Ergang Liu Jianxin Wang Yongzhuo Huang Seung Jin Lee Huining He Tianjin Key Laboratory on Technologies Enabling Development of Clinical Therapeutics and Diagnostics School of PharmacyTianjin Medical University College of Pharmacy Tsinghua University Collaborative Innovation Center of Chemical Science and Chemical Engineering and Technology Tianjin University Key Laboratory of Smart Drug Delivery Ministry of Education & PLA Department of Pharmaceutics School of Pharmacy Fudan University Ministry of Education & PLA Shanghai Institute of Materia Medica Chinese Academy of Sciences Department of Pharmacy Ewha Womans University Seodaemun-gu

RNAi technology has aroused wide public interest due to its high efficiency and specificity to treat multiple types of diseases. However, the effective delivery of siRNA remains a challenge due to its large molecular weight and strong anionic charge. Considering their remarkable functions in vivo and features that are often desired in drug delivery carriers, biomimetic systems for siRNA delivery become an effective and promising strategy. Based on this, covalent attachment of synthetic cell penetrating peptides(CPP) to siRNA has become of great interest. We developed a monomeric covalent conjugate of low molecular weight protamine(LMWP, a well-established CPP) and siRNA via a cytosol-cleavable disulfide linkage using PEG as a crosslinker. Results showed that the conjugates didn't generate coagulation, and exhibited much better RNAi potency and intracellular delivery compared with the conventional charge-complexed CPP/siRNA aggregates. Three different synthetic and purification methods were compared in order to optimize synthesis efficiency and product yield. The methodology using hetero-bifunctional NHS–PEG–OPSS as a crosslinker to synthesize LMWP–siRNA simplified the synthesis and purification process and produced the highest yield. These results pave the way towards siRNA biomimetic delivery and future clinical translation.

关键词： Cell penetrating peptide siRNA Conjugate Conjugation yield Biomimetic delivery crosslinker

New insights into hydraulic fracturing fluids used for hightemperature wells

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Petroleum 2021年第1期7卷 70-79页

作者： Tariq Almubarak Leiming Li Jun Hong Ng Hisham Nasr-El-Din Mohammed AlKhaldi Texas A&M University USA Aramco Services Company Saudi Arabia Saudi Aramco EXPEC ARC Saudi Arabia

Current interest in deep,low-permeability formations(<10 md)demands accelerated development of high-temperature hydraulic fracturing technologies.Conventional guar systems break down above 300°F and require higher po... 详细信息

Current interest in deep,low-permeability formations(crosslinkers,crosslinker delay additives,and pH buffers were examined in this work.Hydrated polymer solutions were crosslinked with a metallic crosslinker between 200 and 400°F.Viscosity measurements were carried out in a highpressure/high-temperature(HP/HT)rheometer to evaluate rheology and thermal stability.Results show that adding a synthetic polymer and a crosslinker with the slowest reaction rate improves the fracturing fluid thermal stability.Of the three other additives tested,oxygen scavengers showed the greatest enhancement to thermal stability while pH buffers showed the least.Through the addition of high-temperature stabilizing additives,the fracturing fluid in this work was able to maintain a stable performance at temperatures up to 400°F.Maintaining the thermal stability of fracturing fluids at a lower polymer loading remains a challenge in the industry.This work proposes techniques that can be used to enhance the thermal stability of fracturing fluids.Deeper knowledge about these different techniques will allow for better additive development and application in the field.

关键词： Oxygen scavenger crosslinker crosslinker delay Shear tolerance High temperature Synthetic polymer CMHPG Buffers

Synthesis and application of novel degradable crosslinkers

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Chinese Chemical Letters 2011年第3期22卷 374-377页

作者： Xin Ce Sui Zhi Feng Fu Yan Shi State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Beijing 100029 China

A novel divinyl ether was synthesized by a convenient method with high yield.Then the divinyl ether was combined with 2- hydroxyethyl methacrylate and acrylic acid,respectively,generating difunctional polymeric crosslinkers with（hemi）acetal structure that was labile in acid.The chemical structures of the divinyl ether and crosslinkers were confirmed by ~1H NMR and elemental analysis.The crosslinkers were employed in free-radical polymerization to prepare polymer gel and gel particles. Due to the（hemi）acetal structure in the crosslinking segment,the polymer gel and particles exhibited degradable ability in strong acid.

关键词： Divinyl ether crosslinker Degradation

Development of Cardanol-Based Polyol via Click Chemistry and Crosslinking with Melamine Formaldehyde Resin for Coating Applications

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Journal of Renewable Materials 2018年第4期6卷 438-449页

作者： Kunal Wazarkar Anagha Sabnis Department of Polymer and Surface Engineering Institute of Chemical TechnologyNathalal Parekh MargMatunga(E)Mumbai 400019India

The research work presented in this article deals with the synthesis of cardanol-based polyol and its curing with hexabutoxymethyl melamine(HBMM)for application in coatings.Cardanol-based polyol was prepared via thiol-ene click reaction using thioglycerol.Unsaturation present in the long chain of cardanol was successfully utilized to synthesize polyol via thiol-ene coupling.The reaction was carried out between cardanol and thioglycerol in the presence of Irgacure 184(photoinitiator)and 1,8-Diazabicyclo[5.4.0]undec-7-ene(catalyst)under UV light for 12 h at 80°C.After completion of the reaction,one mole of thioglycerol was successfully added across the double bond of a fatty chain of cardanol and confirmed by Fourier transform infrared spectroscopy(FTIR)and proton nuclear magnetic resonance spectroscopy and hydroxyl and iodine values were determined.Furthermore,the polyol thus prepared was cured with commercial HBMM in various proportions,such as 1:0.6,1:0.8 and 1:1,on an equivalent basis.The coatings were then characterized for mechanical,chemical,optical,thermal and anticorrosive properties.It was observed that coatings exhibited excellent performance properties as compared to that of its acrylic counterpart.

关键词： CNSL click chemistry HBMM crosslinker anticorrosive sustainable

Polyamine-Polymeric Micelle Hybrid Hydrogel: Microscopic Properties of crosslinkers Affecting Macroscopic Rheological Properties of Hydrogel

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Journal of Biomaterials and Nanobiotechnology 2015年第1期6卷 36-44页

作者： Chikara Yoshida Tomoki Ito Ryosuke Anzai Kengo Fukuda Keita Kinoshita Seiichi Sonotaki Taku Takami Yoshihiko Murakami Department of Organic and Polymer Materials Chemistry Faculty of Engineering Tokyo University of Agriculture and Technology Tokyo Japan

We have developed a hybrid hydrogel that is formed from a crosslinkable polymeric micelle and a polyamine. Under optimal conditions, the hydrogel rapidly formed in one second after a crosslinkable polymeric micelle solution was mixed with a polyamine solution. We could change the hydrogel’s gelation properties, such as the storage modulus and gelation time by tuning the molecular weights of block copolymers and by tuning the pH of the dissolving-solvent of the hydrogel’s constituent components. Furthermore, we have clarified here that the structural difference among the micelles acting as crosslinkers can affect the gelation properties of the hydrogel. According to our findings, the hydrogel that was formed from the polymeric micelles possessing a highly packed (i.e., well-entangled or crosslinked) inner core exhibited a higher storage modulus than the hydrogel that was formed from the polymeric micelles possessing a lowly packed structure. Our results demonstrate that a microscopic structural difference among crosslinkers can induce a macroscopic change in the properties of the resulting hydrogels. For medical applications, the hydrogel proposed in the present paper can encapsulate the hydrophobic compounds in crosslinkers (polymeric micelles) so that the hydrogel can be available as the biomaterial for their sustained release.

关键词： Hydrogel Polymeric Micelle Self-Assembly crosslinker Block Copolymer

Effects of Swelling Processes on the Particle Morphology of Porous P(MMA-EGDMA) Particles via Seeded Two-step Swelling Method

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复旦学报（自然科学版） 2007年第5期46卷 792-页

作者： Yannan Cui, Chengyou Kan(Department of Chemical Engineering, Laboratory of Advanced Materials of Education Ministry, Tsinghua University, Beijing 10084, China) Department of Chemical Engineering Tsinghua University Key Laboratory of Advanced Materials of Education Ministry Beijing 10084

1 Results Porous functional polymer particles have been drawing great interest for their applications in many fields such as ion exchange,polymeric carrier,biomedicine,biochemistry,cosmetics,plastic pigments,and were first prepared by suspension polymerization in 1 950 s.Since 1990's,some approaches such as seeded emulsion polymerization method,dynamic monomer swelling method,activated swelling method and multi-step seeded method[1-4] have been used by many researchers to synthesize this kind of polymer...

关键词： porous morphology swelling process crosslinker PMMA