Article
Materials Science, Multidisciplinary
Riesca Ayu Kusuma Wardhani, Indah Primadona, Andri Hardiansyah
Summary: In this study, electrospun alpha-mangosteen-chitosan-polyethylene oxide (PEO) nanofibers were produced and evaluated for potential biomedical applications.
MATERIALS RESEARCH EXPRESS
(2022)
Article
Chemistry, Multidisciplinary
Meaghan A. Bruening, Shuoyan Xiong, Theodor Agapie
Summary: Linear a-olefins are efficiently prepared from ethylene in the Shell higher olefin process (SHOP), while a general process for the preparation of a range of α,β-dienes is lacking. Here, we report a two-step method that generates industrially relevant α,β-dienes. We demonstrate the generation of a distribution of α,β-dienes in the C10-C20 range through the ethenolysis of copolymers obtained by the copolymerization of ethylene and butadiene.
ACS SUSTAINABLE CHEMISTRY & ENGINEERING
(2023)
Article
Chemistry, Physical
Xiao-Cheng Liu, Cong Wei, Yishang Wu, Yanyan Fang, Wen-Qiang Li, Rong-Rong Ding, Gongming Wang, Yang Mu
Summary: This study demonstrates that enhancing CO2 reduction catalysts through noncovalent interactions can improve the selectivity and activity of SnO catalysts, leading to efficient formate production. Moreover, the introduction of hydroxyl groups can be a general strategy for CO2 hydrogenation on various metal oxides.
Article
Polymer Science
Alexander Kleine, Ulrich S. Schubert, Michael Jaeger
Summary: This study investigates the preparation of poly(N-alkyl-3,6-carbazole)s with defined alpha-/omega-end groups using a commercial Buchwald-type pre-catalyst. It is found that an excess of monofunctional aryl halide favors the Suzuki-Miyaura catalyst-transfer polymerization (SCTP) mechanism, resulting in heterotelechelic polymers with defined molar masses, narrow dispersities, and high chemical yields.
Article
Polymer Science
Neel J. Shah, Sajjad Dadashi-Silab, Michael D. Galluzzo, Saheli Chakraborty, Whitney S. Loo, Krzysztof Matyjaszewski, Nitash P. Balsara
Summary: The study investigated the impact of salt addition on a diblock copolymer system with a negative Flory-Huggins interaction parameter, chi. It was found that ordered phases only appear under specific conditions, as predicted by ionic self-consistent field theory.
Article
Chemistry, Multidisciplinary
Marcel Buerger, Nadine Ehrhardt, Thomas Barber, Liam T. Ball, Jan C. Namyslo, Peter G. Jones, Daniel B. Werz
Summary: A phosphine-catalyzed oligomerization of arynes using selenocyanates has been developed to access alpha, omega-bisfunctionalized oligo(ortho-arylenes). The use of JohnPhos as a bulky phosphine catalyst is crucial for this reaction to occur. Various optimized conditions have been established to predominantly form dimers, but also higher oligomers, up to octamers, depending on the electronic properties of the electrophilic reaction partner. Mechanistic studies show that the cascade reaction starts with cyanide attack and rules out aryne insertion into n-mers leading to (n+1)-mers.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Chemistry, Physical
Steven W. Rick
Summary: A thermal responsive block copolymer made up of ethylene oxide (EO) and propylene oxide (PO) blocks was simulated at different temperatures, showing aggregation behavior in dilute solution that is stabilized by hydrophobic contact of propylene oxide methyl groups. The study compared the aggregation tendency of different polymers in solution and highlighted the importance of hydrophobic interactions in the aggregation process.
JOURNAL OF PHYSICAL CHEMISTRY B
(2021)
Article
Polymer Science
Janaya D. Sachs, Ian A. Tonks
Summary: The Pd-catalyzed carbonylative polymerization of alpha,omega-enol ethers has been reported, allowing the modification of polymer properties by varying the length of the diol fragment in the monomers. This polymerization strategy has been extended to include rigid and bioderived diol moieties, expanding the range of structures and properties accessible.
Article
Environmental Sciences
Esmaeel Sharifi, Rezvan Jamaledin, Fatemeh Familsattarian, Fereshteh Nejaddehbashi, Mitra Bagheri, Mohammad Chehelgerdi, Ehsan Nazarzadeh Zare, Omid Akhavan
Summary: This research evaluated the potential of bioactive chitosan@poly (ethylene oxide)@CuFe2O4 (CS@PEO@CF) nanofibers in wound healing. The nanoparticles showed antibacterial and antioxidant properties and did not adversely affect fibroblast cell viability. The nanofibrous mats promoted cell migration and growth at the wound edge, leading to enhanced wound healing and regeneration of sebaceous glands and hair follicles within the skin.
ENVIRONMENTAL RESEARCH
(2023)
Article
Chemistry, Physical
Le-Cheng Wang, Xiao-Feng Wu
Summary: In this study, we have developed an unprecedented and general method for the direct synthesis of various alpha-amino acid derivatives by activating inert C-H bonds. By introducing an appropriate electron-withdrawing group, we successfully modulated the nucleophilicity and polarity of the reaction, resulting in a broad substrate scope and excellent tolerance of sensitive functional groups in this catalytic strategy.
JOURNAL OF CATALYSIS
(2023)
Article
Polymer Science
Congzhi Zhu, Aaron A. Burkey, Cameron P. Adams, Diego Uruchurtu Patino, Nathaniel A. Lynd
Summary: Orthoester-containing copolymers are degradable under mild acidic conditions, making them suitable for applications in drug delivery, photolithography, and disposable plastics with environmental remediation. These copolymers combine the degradation properties of polyorthoesters with the structural diversity of polyethers.
Article
Chemistry, Multidisciplinary
Peng Zhou, Zixian Li, Yanzhi Lu, Jie Kong, Jun Ling
Summary: The study demonstrates that the triblock PAA-NHO-PTHF-ONH-PAA has high molecular weight and narrow dispersity, suitable for applications as polyether-poly(amino acid)s block copolymers. Due to the presence of oxygen amide groups in the backbone, these copolymers are cleavable under acidic conditions, showing potential in smart biomedicine and engineering.
CHINESE JOURNAL OF CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
Minghao Feng, Roberto Tinelli, Ricardo Meyrelles, Leticia Gonzalez, Boris Maryasin, Nuno Maulide
Summary: This study reports a practical method for the synthesis of alpha-amino acid derivatives via direct hydrative amination of activated alkynes using sulfinamides as the nitrogen source under mild conditions. Computational studies suggest that the reaction is enabled by a new type of sulfonium [2,3]-sigmatropic rearrangement.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Polymer Science
Zhao-Xuan Liu, Tie-Qi Xu
Summary: Through a fundamental structure/property study, the effects of steric hindrance/electronic properties of the monomer, spacer length between sulfur atom and olefin group, and stereoselectivity of the polymerization process on the crystalline performance of sulfur-functionalized poly(alpha-olefin) were revealed. The first crystalline sulfur-functionalized poly(alpha-olefin) was reported, which formed crystalline materials with a high melting point.
Article
Polymer Science
Xiangning Wen, Yunlan Su, Shaofan Li, Weilong Ju, Dujin Wang
Summary: The study demonstrated that PEG-g-SiO2 can significantly increase the crystallinity and crystallization temperature of PEO matrix, affecting the crystalline morphology and rate of PEO. The good dispersion of PEG-g-SiO2 in the PEO matrix contributes to enhancing the primary nucleation rate.
Article
Polymer Science
Guisheng Jiao, Taisen Zuo, Changli Ma, Zehua Han, Junrong Zhang, Ye Chen, Junpeng Zhao, He Cheng, Charles C. Han
Article
Chemistry, Multidisciplinary
Yening Xia, Georg M. Scheutz, Charles P. Easterling, Junpeng Zhao, Brent S. Sumerlin
Summary: This study introduces a method for synthesizing well-defined polyacrylamido-b-polyether block copolymers by combining photoiniferter polymerization and organocatalytic ring-opening polymerization. The compatibility between the two polymerization systems is demonstrated, allowing for the tailored synthesis of block copolymers from chemically distinct monomers.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Polymer Science
Tao Lai, Pengfei Zhang, Junpeng Zhao, Guangzhao Zhang
Summary: The study discovered a novel copolymerization method for synthesizing a nearly unexplored sulfur-containing polymer PTC, controlled by a simple catalyst resulting in high quality products. The method also demonstrates selectivity towards different reactants, offering a new strategy for preparing tailor-made polymers.
Article
Chemistry, Analytical
Blaz Zdovc, Heng Li, Junpeng Zhao, David Pahovnik, Ema Z. Agar
Summary: The influence of microstructure on the chromatographic behavior of gradient copolymers and block copolymers was studied using gradient liquid adsorption chromatography and liquid chromatography at critical conditions. The results indicate that in addition to chemical composition and molar mass, microstructure also plays an important role in the elution behavior of gradient copolymers.
ANALYTICAL CHEMISTRY
(2022)
Article
Agriculture, Multidisciplinary
Jing Wu, Junpeng Zhao, Yubo Zhou, Chun Cui, Jucai Xu, Laihao Li, Yunzi Feng
Summary: A structure-based virtual screening was used to identify taste-active N-Lac-AAs, with N-L-Lac-L-Trp showing higher affinity for taste receptors. N-L-Lac-L-Trp was synthesized and its chemical structure was confirmed. Sensory evaluation revealed that N-L-Lac-L-Trp had a significant taste-masking effect on quinine, D-salicin, caffeine, and L-Trp, particularly L-Trp and caffeine.
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Qilei Song, Hong Qiu, Lijun Liu, Guangzhao Zhang, Frederic Peruch, Stephane Carlotti, Junpeng Zhao
Summary: One-step sequence-selective block copolymerization requires strict catalytic control of monomer activity and enchainment order, especially for A(n)B(m)-type block copolymers from simple binary monomer mixtures. In this study, ethylene oxide (EO) and N-sulfonyl aziridine (Az) form a valid pair with a bicomponent metal-free catalyst. The optimal Lewis acid/base ratio allows the two monomers to block-copolymerize strictly in a reverse order (EO-first) compared to the conventional anionic route (Az-first). The livingness of the copolymerization enables the one-pot synthesis of multiblock copolymers by adding mixed monomers in batches. Calculation results suggest that the Janus effect of Lewis acid on the two monomers is crucial for enlarging the activity difference and reversing the enchainment order.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Polymer Science
Huitong Luo, Yubo Zhou, Qingtao Li, Boru Zhang, Xiaodong Cao, Junpeng Zhao, Guangzhao Zhang
Summary: Recently, Lewis pairs composed of organobases and organoboranes have shown high catalytic activity for the synthesis of polyethers by ring-opening polymerization of epoxides. The unexpected chemoselectivity was attributed to the protonolysis of Et3B and the reversible interchange of acyloxyborane and borinic ester at the propagating chain ends, which suppressed the reaction between hydroxy species and epoxide while maintaining the catalytic activity for the reaction between carboxy species and epoxide. Additionally, the polyesters containing catalyst residues exhibited good cytocompatibility.
Article
Polymer Science
Lijun Liu, Junpeng Zhao, Guangzhao Zhang
Summary: In this study, a simple one-pot synthesis of α-thiol-ω-hydroxylpolyethers was reported, achieved through ring-opening polymerization (ROP) of epoxides using thiocarboxylic acid initiators followed by in situ aminolysis. The metal-free Lewis pair catalyst utilized in this method allowed for efficient and chemoselective polymerization, resulting in controlled molar mass, low dispersity, and high end-group fidelity. The stability of thioester during the ROP also allowed for the synthesis of α-thiol-ω-dihydroxyl (Y-shaped) PEO, which exhibited enhanced protein resistance behavior due to the intensified interaction with gold surfaces.
Article
Polymer Science
Shan Liu, Lijun Liu, Yubo Zhou, Ye Chen, Junpeng Zhao
Summary: In this study, linear polyglycerols were synthesized using commercial glycidyl butyrates, and the control over the molar mass and stereoregularity of the polymers was achieved. The copolymerization of glycidyl butyrates with other monomers resulted in copolyethers with different aqueous thermosensitivity.
Article
Chemistry, Analytical
Blaz Zdovc, Heng Li, Junpeng Zhao, David Pahovnik, Ema Z. Agar
Summary: This study investigates the influence of microstructure on the chromatographic behavior of copolymers. The results show that the elution volume of copolymers increases with the increasing strength of the gradient. This study highlights the importance of considering the effect of microstructure in addition to the chemical composition and molar mass when analyzing copolymers using liquid interaction chromatography methods.
ANALYTICAL CHEMISTRY
(2022)
Article
Polymer Science
Georg M. Scheutz, Justine Elgoyhen, Kyle C. Bentz, Yening Xia, Hao Sun, Junpeng Zhao, Daniel A. Savin, Brent S. Sumerlin
Summary: This study demonstrates the photoinduced intrachain crosslinking of coumarin-containing copolymers in various organic solvents, with solvophobicity-driven crosslinking kinetics and chain compaction facilitating the synthesis of single-chain nanoparticles.
Article
Chemistry, Multidisciplinary
Shan Liu, Lijun Liu, Ye Chen, Junpeng Zhao
CHEMICAL COMMUNICATIONS
(2020)