Article
Polymer Science
Ting Shen, Xu-feng Ni, Jun Ling
Summary: Rare earth (RE) catalysts exhibit high catalytic activity in ring-opening polymerization, allowing for high molecular weight and polymerization rate and expanding the polymerization scope to traditionally non-polymerizable monomers. They also enable stereoselective polymerization and tailored polymer structures through slight modifications of ligands. The unique advantages of RE catalysts in controlling polymerization and structure are illustrated, along with a novel Janus polymerization mechanism providing a facile methodology to synthesize polymers with sophisticated chemical structures and topologies in one step. New catalysts and mechanisms of ring-opening polymerizations show potential in creating new materials.
ACTA POLYMERICA SINICA
(2021)
Article
Polymer Science
Monique J. Leite, Tamara Agner, Fabricio Machado, Brenno A. D. Neto, Pedro H. H. Araujo, Claudia Sayer
Summary: This study utilized an iron-containing imidazolium-based ionic liquid as a catalyst to efficiently catalyze the ring-opening polymerization of epsilon-caprolactone under mild reaction conditions, resulting in the synthesis of polycaprolactones with high yields and narrow molecular weight distributions.
JOURNAL OF POLYMER RESEARCH
(2022)
Article
Chemistry, Multidisciplinary
Maosheng Li, Shuai Zhang, Xiaoyong Zhang, Yanchao Wang, Jinlong Chen, Youhua Tao, Xianhong Wang
Summary: The study describes an effective unimolecular anion-binding organocatalysis for ring-opening polymerization of O-carboxyanhydrides (OCAs), achieving the synthesis of highly isotactic poly(phenyllactic acid) (Ph-PLA) through a dynamic cooperative anion-binding mechanism. This approach addresses the challenge of synthesizing high molecular weight stereoregular polyesters by facilitating efficient chain propagation and maintaining high selectivity for OCA ring-opening over side reactions.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Polymer Science
Rebecca Mohr, Manfred Wagner, Sirus Zarbakhsh, Holger Frey
Summary: The combination of hydrophobic PDMS blocks with hydrophilic polyether segments plays a key role for silicone surfactants in this study. Using DMC catalyst, direct copolymerization of cyclic siloxanes and epoxides is achieved, leading to the formation of gradient PPO-PDMS copolymers. Contact angle measurements show increased hydrophobicity and a glass transition of -95 degrees C for copolymers with 46% SiO content.
MACROMOLECULAR RAPID COMMUNICATIONS
(2021)
Review
Chemistry, Multidisciplinary
Bokun Li, Chenyang Hu, Xuan Pang, Xuesi Chen
Summary: This Review provides an overview of a redox-controlled switchable strategy for controlled synthesis of polymers. By developing valence-variable metal-based catalysts, high sequence-control and easy-handling in ring-opening (co)polymerizations can be achieved, resulting in polymer products with desired microstructures and practical performances.
CHEMISTRY-AN ASIAN JOURNAL
(2023)
Review
Chemistry, Applied
Farah Naz, Rahaman M. Abdur, Fatima Mumtaz, Mirella Elkadi, Francis Verpoort
Summary: This study reviews the application of heterogeneous catalysts in the ring-opening polymerization of cyclic esters, with a focus on metal-organic frameworks (MOFs) and supported catalysts. The importance of precise design and catalyst stability is emphasized in controlling polymerizations.
APPLIED ORGANOMETALLIC CHEMISTRY
(2023)
Article
Chemistry, Inorganic & Nuclear
Anand J. Gaston, Zoe Greindl, Carole A. Morrison, Jennifer A. Garden
Summary: This study describes four heterobimetallic (salen)Al catalysts and demonstrates that cooperative Al/Mg and Al/Zn combinations can significantly enhance catalyst activity, compared to mono-Al analogues. In contrast, Al/Li and Al/Ca combinations were found to inhibit the polymerization rate. Kinetic and computational studies suggest that chloride bridging in close intermetallic proximity enhances initiation and increases available monomer coordination sites in Al/Mg and Al/Zn complexes. Additionally, ab initio molecular dynamics calculations were utilized to investigate catalyst flexibility and reveal that ligand strain and molecular rigidity can enhance the performance of heterometallic catalysts.
INORGANIC CHEMISTRY
(2021)
Review
Chemistry, Inorganic & Nuclear
Ling-Jo Wu, Wei Lee, Prasanna Kumar Ganta, Yu-Lun Chang, Yung -Chi Chang, Hsuan-Ying Chen
Summary: Multinuclear metal complexes can enhance the catalytic activity of ROP catalysts, but the distance between catalytic metal centers and the resonance of ligands play important roles in the catalytic reaction. This review focuses on recent studies of multinuclear metal catalysts in ROP and compares their catalytic activity with mononuclear metal catalysts.
COORDINATION CHEMISTRY REVIEWS
(2023)
Review
Polymer Science
Takuya Isono
Summary: This focused review provides an overview of recent work and related research on the precise anionic ring-opening polymerization (AROP) of substituted epoxides using t-Bu-P-4 as the phosphazene base catalyst to produce functional polyethers. The fundamental aspects and applicable monomer scope of the t-Bu-P-4-catalyzed AROP are discussed, followed by applications of the AROP system for synthesizing functional materials and architectural polymers.
Article
Polymer Science
Yongzhuang Du, Xiaoqiang Xue, Qimin Jiang, Wenyan Huang, Hongjun Yang, Li Jiang, Bibiao Jiang, Sridhar Komarneni
Summary: This study investigated the ring-opening mechanism of epoxides in the presence of tertiary amines. Gas chromatography (GC) and size-exclusion chromatography (SEC) were used to analyze monomer conversion and molecular weights of the polymers. Nuclear magnetic resonance (NMR) spectroscopy was employed to examine polymer structures. The results showed that the ring-opening reaction only occurred when tertiary amines and hydroxyl-containing compounds were present together, indicating an interaction between tertiary amines and hydroxyl groups. The mechanisms of ring-opening reactions catalyzed by tertiary amines varied depending on the structures of the epoxides.
Article
Polymer Science
Jian Lin, Peng Wang, Lei Fan, Tian Xiao, Jianhua Cheng, Xia Chen
Summary: Bi- and tetra-lithium quinolyl/pyridyl-amino complexes were synthesized and characterized, showing high catalytic activity in the polymerization of rac-lactice and e-caprolactone. The number of metal centers and ligand structures were found to be crucial factors in determining the reactivity of the catalyst in ring-opening polymerization (ROP).
Review
Polymer Science
Jiaxi Xu, Xin Wang, Jingjing Liu, Xiaoshuang Feng, Yves Gnanou, Nikos Hadjichristidis
Summary: Ring-opening polymerization (ROP) is a prevalent and convenient method for synthesizing well-defined polymers with initiators/catalysts. One of the challenges faced by ROP catalysts is the selective activation of functional groups or linkages of the monomer without those carried out in the polymer chains, especially at high conversion. H-bonding organocatalysts can offer precise selectivity for ROP in a wide range of monomers.
PROGRESS IN POLYMER SCIENCE
(2022)
Article
Chemistry, Multidisciplinary
Xiao Jiang, Na Zhao, Zhibo Li
Summary: A bifunctional H-bonding catalyst SQ-1 and the binary H-bonding catalytic system consisting of squaramides (SQ-2 to SQ-6) and DBU were discovered to efficiently promote the stereoselective ring-opening polymerization (ROP) of rac-lactide at room temperature. The resulting polylactides exhibited controlled molecular weights and high tacticity.
CHINESE JOURNAL OF CHEMISTRY
(2021)
Article
Polymer Science
Chinh-Hoang Tran, Min-Woong Lee, Soo-Jeong Lee, Jin-Hyeok Choi, Eun-Gyeong Lee, Ha-Kyung Choi, Il Kim
Summary: A series of heterogeneous Zn-Co double metal cyanide (DMC) catalysts were investigated for ring-opening polymerization (ROP) of various cyclic monomers. It was found that inexpensive and commonly used organic solvents were effective complexing agents for the preparation of DMC catalysts, which showed high catalytic activity for the ROP of propylene oxide, epsilon-caprolactone, and delta-valerolactone. The chemical structures and compositions of the catalysts were determined using various techniques, and alpha, omega-hydroxyl-functionalized polyether and polyester polyols with high yields and tunable molecular weights were successfully synthesized in the presence of different initiators. Kinetic studies of the ROP of delta-valerolactone were also conducted to confirm the reaction mechanism.
Article
Polymer Science
Zexi Wu, Caijie Shi, Tao Peng, Qiannan Cheng, Qingquan Tang, Luoxin Wang, Hua Wang, Siwei Xiong
Summary: This study investigates the catalytic effect of ionic liquids (ILs) on the polymerization of liquid crystal aromatic polyesters (LCAPs). The results showed that 1-ethyl-3-methylimidazolium acetate had the best catalytic effect under the conditions of 210 degrees C temperature and 0.5 wt% catalyst concentration.
JOURNAL OF APPLIED POLYMER SCIENCE
(2023)
Article
Polymer Science
Yanping Li, Songyi Xu, Jun Ling, Ke Pan, Yujian Liu, Yougen Chen
Summary: This study presents a novel controlled/living ring-opening polymerization method for epsilon-caprolactone and delta-valerolactone using EDPP and DPP. The unique equilibrium reaction between the active phosphinite center and its protonated dormant species plays a crucial role in achieving controlled polymerization. The living nature of the polymerization process is confirmed through kinetic studies and chain extension experiments, leading to the synthesis of polyesters with controlled molar masses and moderate dispersities.
Article
Chemistry, Multidisciplinary
Bo Song, Tianwen Bai, Dongming Liu, Rong Hu, Dan Lu, Anjun Qin, Jun Ling, Ben Zhong Tang
Summary: In this study, CO2-based polyesters were successfully degraded into high-value derivatives through controlled reaction conditions. The degradation process was visualized and applied in various fields such as bioimaging and waste recovery, solving the end-of-life issue of polymers.
Article
Biochemistry & Molecular Biology
Peng Zhou, Tianlun Shen, Wanli Chen, Jihong Sun, Jun Ling
Summary: Polysarcosine (PSar) is a water-soluble polypeptoid with biodegradability and biocompatibility. Under specific conditions, PSar can be degraded by enzymes and its molecular weight and alanine content can be controlled. The water solubility and biodegradability of PSar depend on the alanine residue content, and its noncytotoxicity offers potential applications in drug delivery.
Article
Polymer Science
Jiawen Song, Kaihao Chen, Yuanhao Feng, Xufeng Ni, Jun Ling
Summary: This study presents a novel one-pot orthogonal strategy for the utilization of disubstituted delta-valerolactone in the synthesis of a series of amphiphilic polymers, which hold significant implications for the transformation of carbon dioxide.
JOURNAL OF POLYMER SCIENCE
(2022)
Article
Polymer Science
Yan-Zhi Lu, An-Qi Gu, Tian-Lun Shen, Ji-Hong Sun, Jun Ling
Summary: Modifications at polypeptide side chains have been found to affect conformation and properties. The synthesis of poly(S-allylcysteine) (PAC) with unsaturated bonds and thioether moieties provides active binding sites and enzymatic catalytic sites. These polypeptides may find applications in drug delivery, biosensing, and nanoreactor.
CHINESE JOURNAL OF POLYMER SCIENCE
(2022)
Article
Engineering, Biomedical
Yuwen Lu, Tanchen Ren, Hua Zhang, Qiao Jin, Liyin Shen, Mengqi Shan, Xinzhe Zhao, Qichao Chen, Haoli Dai, Lin Yao, Jieqi Xie, Di Ye, Tengxiang Lin, Xiaoqian Hong, Kaicheng Deng, Ting Shen, Jiazhen Pan, Mengyan Jia, Jun Ling, Peng Li, Yue Zhang, Huanan Wang, Lenan Zhuang, Changyou Gao, Jifu Mao, Yang Zhu
Summary: This study fabricated stiff polymeric microneedles with backward-facing barbs inspired by honeybee stingers and embedded them into elastomer films to produce self-interlocking microneedle patches. The barbing pattern was adjusted to increase interlocking efficiency. The microneedle patches demonstrated strong tissue adhesion and were successfully implanted onto beating hearts. They reduced cardiac wall stress and maintained left ventricular function. The microneedle patches were minimally invasive and did not require sutures or adhesives.
ACTA BIOMATERIALIA
(2022)
Article
Engineering, Biomedical
Jingya Xia, Liying Wang, Tianlun Shen, Ping Li, Peiyun Zhu, Shengnan Xie, Zhenyan Chen, Fei Zhou, Jingfeng Zhang, Jun Ling, Xiangrui Liu, Hong Yu, Jihong Sun
Summary: Despite the initial promise of photothermal ablation (PTA) therapy, the inability to completely ablate large tumors is problematic. This study developed a smart photothermal nanosystem (PBM) based on FDA-approved Prussian blue (PB) nanoparticles, doped with Mn (III) to address this issue. The PBM nanosystem amplified the PTA-induced cGAS-STING pathway, leading to a robust immune response and suppression of both local residual and distant tumors.
ACTA BIOMATERIALIA
(2023)
Article
Chemistry, Multidisciplinary
Yixuan Mei, Kaihao Chen, Jiayu Gu, Jun Ling, Xufeng Ni
Summary: This study reports the successful synthesis of a copolymer of 2-methyltetrahydrofuran (2-MeTHF) and beta-butyrolactone (BBL) through Sc(OTf)(3)-catalysed cationic ring-opening copolymerization. The possibility of copolymerization was verified by density functional theory (DFT) calculations. The obtained copolymer, poly(2-MeTHF-co-BBL), showed promising properties and potential as an environmentally friendly material.
Article
Nanoscience & Nanotechnology
Kai Hao, Ronglu Cui, Lifeng Fang, Jun Ling, Baoku Zhu
Summary: In this study, a neutral surface of polysarcosine (PSar), a hydrophilic polypeptoid, was successfully synthesized and modified to enhance its compatibility with water, reduce protein adsorption and cytotoxicity, and demonstrate good hemocompatibility and antifouling properties.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Polymer Science
Siqi Wang, Tianlun Shen, Kai Hao, Xinfeng Tao, Jihong Sun, Jun Ling
Summary: Hyperbranched poly(a-amino acid)s have attracted attention for their biocompatibility, degradability, and bioactivity. Unique polymerization reactions of di-NNPC resulted in hyperbranched polypeptoids instead of gels. The molecular weights of the hyperbranched polypeptoids were controlled by tuning the initial concentrations of monomer and basic catalyst. The residual glycine pendant groups on the polymer chains were used for Gd3+ complexation and post-modification, making the hyperbranched polypeptoids multifunctional single molecular micelles applicable as contrast agents and probes in magnetic resonance imaging and photoluminescence.
MACROMOLECULAR CHEMISTRY AND PHYSICS
(2023)
Review
Polymer Science
Ting Shen, Kaihao Chen, Yougen Chen, Jun Ling
Summary: To address the plastic waste crisis, there are efforts to develop sustainable polymer materials that can degrade through disposing and decomposing to small molecules (DDM) or via chemical recycling to monomers (CRM). Polyacetals, a type of pH-responsive polymers, can degrade under acidic conditions but remain stable under neutral and basic conditions. Their synthesis through cationic ring-opening polymerization (CROP) has challenges but recent advancements in CRM have renewed interest in this method. Polyacetals offer recyclable materials with DDM and CRM potential, expanding closed-loop recycling options and improving degradation properties of traditional polyesters and polyolefins.
MACROMOLECULAR RAPID COMMUNICATIONS
(2023)
Article
Multidisciplinary Sciences
Jie Zhang, Tianwen Bai, Weixi Liu, Mingzhao Li, Qiguang Zang, Canbin Ye, Jing Zhi Sun, Yaocheng Shi, Jun Ling, Anjun Qin, Ben Zhong Tang
Summary: High refractive index polymers (HRIPs) with excellent optical transparency are prepared by using organobase catalyzed polymerization. The HRIPs exhibit high refractive indices, high molecular weights, and low propagation loss. The polymers also have aggregation-induced emission feature for monitoring the uniformity and continuity of optical waveguides.
NATURE COMMUNICATIONS
(2023)
Review
Chemistry, Multidisciplinary
Kaihao Chen, Yixuan Mei, Zhuorui Zhang, Jun Ling, Xufeng Ni
Summary: As a substituted-delta-valerolactone, alpha-ethylidene-delta-vinyl-delta-valerolactone (EVL) offers a method to utilize carbon dioxide and 1,3-butadiene in producing functional polymers. Recent successful attempts in polymerizing EVL have led to the development of novel synthetic strategies and functional polymers. This review highlights the ring-opening reactions of EVL and its derivatives, as well as the ring-opening (co)polymerizations, showcasing the unique properties of the obtained functional polymers and their application potential in various fields.
Article
Polymer Science
Jianping Wang, Peng Zhou, Ting Shen, Songyi Xu, Tianwen Bai, Jun Ling
Summary: This study developed a novel method to synthesize glycine-rich poly-(amino acid)-s (PAAs) through controlled ring-opening copolymerization. The synthesized copolymers exhibited predictable molecular weights and tunable glycine incorporation, and could form nanoparticles or hydrogel in water. The beta-sheet folding of poly-(Gly-r-Lys) remained intact in a neutral environment. This strategy opens up new possibilities for engineering glycine-rich PAAs and expanding their applications.
Article
Materials Science, Biomaterials
Shangyu Chen, Peng Zhou, Wan Yang, Danni Hu, Pengfei Chen, Pengfei Sun, Jun Ling, Quli Fan
Summary: In this study, a modified near-infrared II (NIR-II) small-molecule-based polymer was prepared for efficient breast cancer pulmonary metastasis imaging. The polymer showed good solubility, high fluorescence quantum yield, and prolonged blood circulation half-life, and demonstrated better tumor accumulation capability even at low dye concentration. The successful use of this polymer in noninvasive NIR-II fluorescence imaging for breast cancer pulmonary metastasis was demonstrated.
BIOMATERIALS SCIENCE
(2023)
