Article
Chemistry, Multidisciplinary
Z. N. Nysenko, E. E. Said-Galiev, G. G. Nikiforova, M. Buzin, A. A. Glazkov, M. M. Il'in, G. A. Belyaev, V. V. Rusak, A. M. Sakharov
Summary: High-molecular-weight polymers with varying contents of propylene carbonate (PC) and trimethylene carbonate (TMC) units were synthesized by coordination anionic copolymerization in supercritical carbon dioxide. The terpolymerization products were characterized and their thermal behavior was studied.
RUSSIAN CHEMICAL BULLETIN
(2022)
Article
Polymer Science
Wenjie Mo, Chunwei Zhuo, Shunjie Liu, Xianhong Wang, Fosong Wang
Summary: This study presents a facile strategy to transform brittle plastic PCHC into an elastomer by introducing Cu-S dynamic reversible bonds and performing CO2/CHO/vinyl cyclohexene oxide terpolymerization, followed by thiol-ene click chemistry and Cu-S coordination postfunctionalization. The resulting thermoplastic elastomers exhibit good elastic recovery and adjustable mechanical properties.
Article
Polymer Science
Yi-Le Zhang, Wen-Zhen Wang, Li Wang, Lei-Lei Li, Kai-Yue Zhang, Sai-Di Zhao
Summary: This study presents a thermoplastic PPC with cross-linked networks synthesized by copolymerization, showing excellent thermal and mechanical properties as well as dimensional stability.
Article
Chemistry, Inorganic & Nuclear
Yongmoon Yang, Jong Doo Lee, Yeong Hyun Seo, Ju-Hyung Chae, Sohee Bang, Yeon-Joo Cheong, Bun Yeoul Lee, In-Hwan Lee, Seung Uk Son, Hye-Young Jang
Summary: This study presents a new approach to enhance the catalytic activity in CO2 polymerization by using two-dimensional (2D) ZnGA. A porous granular Co-modified ZnGA (Co-ZnGA) was prepared by treating morphology-controlled 2D ZnGA with H3Co(CN)(6). Co-ZnGA exhibited significant catalytic activity in copolymerization of various epoxides and CO2.
DALTON TRANSACTIONS
(2022)
Article
Polymer Science
Chao Chen, Yves Gnanou, Xiaoshuang Feng
Summary: This research describes the design and synthesis of organoboron catalysts for the alternating ring-opening copolymerization (ROCOP) of CO2 with cyclic ethers. The performance of these catalysts was assessed by considering various parameters, such as the type of boron center, the distance between the boron center and the ammonium cation, and the size of the substituents of the cation. Among all the boron-based catalysts, borinane-based catalyst 5 showed the highest productivity in the copolymerization of CO2 and epoxides. Additionally, catalyst 5 could be easily recycled and used as a difunctional initiator. Density Functional Theory computation provided insights into the mechanism of the bifunctional catalyst-mediated CO2 copolymerization and highlighted the importance of the type of boron centers in the overall performance.
Article
Materials Science, Multidisciplinary
Wenzhen Wang, Xiangmin Zhang, Weiwei Han, Jian Huang, Yile Zhang, Chen Zhao, Leilei Li
Summary: A functional monomer chlorendic anhydride (CA) was successfully added to the polymerization reaction between CO2 and propylene oxide (PO) to create a terpolymer plastic polycarbonates (PPCCA), which exhibited improved thermal properties, mechanical properties, dimensional stability, high degradation, and flame retardancy (FR) properties compared to conventional poly(propylene carbonate) (PPC). The addition of 5 mol% CA led to increased degradation temperatures and strength, decreased elongation at break, reduced hot-set elongation and permanent deformation, and improved flame retardancy.
MATERIALS TODAY COMMUNICATIONS
(2023)
Article
Polymer Science
Jiraya Kiriratnikom, Jiafang Guo, Xiaohan Cao, Munir Ullah Khan, Chengjian Zhang, Xinghong Zhang
Summary: This study presents a facile method to improve the optical properties of polycarbonate by introducing sulfur atoms into its chains. The one-pot/one-step synthesis of sulfur-containing polycarbonate was achieved using propylene oxide, carbon dioxide, and carbonyl sulfide, with the catalytic effect of a metal-free Lewis acid-base pair. The obtained terpolymers exhibit high molecular weight, narrow dispersity, and adjustable gradient sequence of thiocarbonate units by varying the feed ratio of carbonyl sulfide.
JOURNAL OF POLYMER SCIENCE
(2022)
Article
Polymer Science
Thomas M. McGuire, Ella F. Clark, Antoine Buchard
Summary: In this study, a D-xylose 3,5-anhydrosugar derivative was used as an oxetane co-monomer in the ring-opening copolymerization (ROCOP) with cyclic anhydrides to synthesize a family of seven novel sugar-derived polyesters with up to 100% renewable content. These polyesters are thermally robust and exhibit a broad range of glass-transition temperatures, allowing for further postpolymerization functionalization. The living character of the ROCOP process was also utilized to synthesize block copolymers through sequential co-monomer addition experiments.
Article
Chemistry, Multidisciplinary
Yan Yu, Bang Gao, Ye Liu, Xiao-Bing Lu
Summary: This study reports a highly efficient chemical recycling method to depolymerize CO2-based alicyclic polycarbonates into epoxide monomers. The method is solvent-free and exhibits excellent reactivity and high epoxide monomer selectivity.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Polymer Science
Jin-Chuang Yang, Jun Yang, Tie-Ying Zhang, Xin-Jun Li, Xiao-Bing Lu, Ye Liu
Summary: The development of biodegradable and recyclable polymers has partially solved the problem of realizing a sustainable plastics economy. This study focuses on toughening poly(3-hydroxybutyrate) (P3HB), a highly crystalline thermoplastic material, by reducing its crystallinity through catalytic carbonylative terpolymerization with different enantiopure epoxides. The properties of the resulting PHA copolymers can range from viscous oil to tough/ductile and brittle plastics, depending on the structure and stereochemistry of the epoxides used.
Article
Chemistry, Multidisciplinary
Guan-Wen Yang, Cheng-Kai Xu, Rui Xie, Yao-Yao Zhang, Xiao-Feng Zhu, Guang-Peng Wu
Summary: This study presents pinwheel-shaped organoboron catalysts for the copolymerization of epichlorohydrin and CO2, achieving high polymer selectivity and quantitative CO2 uptake under mild conditions. The produced poly(chloropropylene carbonate) exhibits the highest molecular weight and glass transition temperature reported to date. The metal-free catalyst shows robust performance and potential for advancing CO2-based polycarbonates.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Pharmacology & Pharmacy
Ekta Singh, Riyaz Ali M. Osmani, Rinti Banerjee, Amr Selim Abu Lila, Afrasim Moin, Khaled Almansour, Hany H. Arab, Hadil Faris Alotaibi, El-Sayed Khafagy
Summary: This study developed leflunomide-loaded nanoparticles as a local drug delivery system for the treatment of rheumatoid arthritis. The nanoparticles showed sustained drug release in simulated synovial fluid and demonstrated efficacy in reducing inflammation and immune responses without notable toxicity in animal models. These findings suggest that intra-articularly administered leflunomide nanoparticles could be a potential alternative to systemic drugs for the treatment of rheumatoid arthritis.
Article
Polymer Science
Victoria J. Barber, Meredith A. Borden, Jill W. Alty, Ly D. Tran, Hilmar Koerner, Luke A. Baldwin, Erik J. Alexanian, Frank A. Leibfarth
Summary: There is an increasing demand for degradable polymers in sustainable plastics and medical implants. To improve their usability, it is necessary to have a better understanding of degradation factors and develop new tools for modulation. In this study, poly(caprolactone) was modified through C-H xanthylation, resulting in changes in material properties and slower degradation. The interplay between molecular and materials characteristics was found to impact the degradation rate.
Article
Polymer Science
Jingjing Liu, Mingchen Jia, Yves Gnanou, Xiaoshuang Feng
Summary: This study presents the synthesis of CO2-based triblock copolymers with a central poly(ether carbonate) block surrounded by two polylactide blocks. By adjusting the CO2 pressure during copolymerization, the glass transition temperature of the central block can be fine-tuned, allowing the synthesis of poly(propylene oxide-co-propylene carbonate) with different carbonate versus ether contents. The resulting triblock copolymers exhibit improved ductility compared to the parent copolymers and outperform commercial polyolefins in terms of mechanical properties.
Article
Chemistry, Inorganic & Nuclear
Ts'epo R. Tumeli, Juanita L. van Wyk
Summary: A series of new ionic functionalized chromium and cobalt complexes derived from salicylaldimine ligands were synthesized and characterized. The complexes exhibited catalytic activity for the coupling of CO2 and propylene oxide, producing propylene carbonate as the coupling product without the need for a cocatalyst.
INORGANICA CHIMICA ACTA
(2021)
