POLYMER
·
2025
·
IF 4.5
Naifan Dong,Jintang Duan,Cailiang Zhang,Xueping Gu,Lianfang Feng,Liu Liu
Polysiloxanes with amino functional groups exhibit remarkable backbone flexibility, lubricity, and softness, positioning them a promising class of polymer materials. The phosphazene base (Bu-t-P 4 ) serves as an effective catalyst for the ring-opening copolymerization (ROCP) of octamethylcyclotetrasiloxane (D 4 ) and N-β-(aminoethyl)-γ-aminopropylmethyldiethoxysilane (KH-602). Under catalysis by 100 ppm of Bu-t-P 4 at 110 °C for 1 h, high yield of 93.59 % was achieved, resulting in amino silicone oil with a number-average molecular weight of 4.3 × 10 3 g/mol, and a narrow molecular weight distribution (2.00). Fourier-transform infrared spectroscopy and nuclear magnetic resonance (NMR) confirmed that the product's structure corresponds to expected chemical shifts. In situ Raman spectroscopy monitoring and NMR analysis was employed to propose and validate the polymerization mechanism within the Bu-t-P 4 -catalyzed system involving both cyclic and linear monomers. This study demonstrates an effective strategy, affirming that Bu-t-P 4 can be used as an efficient organic catalyst for the modified polysiloxanes.
研究领域:
材料科学
·
有机化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMISTRY-A EUROPEAN JOURNAL
·
2021
·Vol. 27
·期 29
·7897-7907
·
IF 5.236
Mengdong Guo,Yue Huang,Zhongkai Chen,Yangping Zhang,Ya Zhang,Mingquan Zhu,Jie Zhang,Shengyu Feng
Graphical Ring-opening copolymerization of benzylsulfonyl macroheterocyclosiloxane and five different cyclosiloxanes was systematically investigated for the first time. A general approach for the synthesis of benzylsulfonyl-containing silicone copolymers with various substituents, including methyl, vinyl, ethyl, and phenyl, was developed herein. Notably, the obtained polymers with adjustable structures and benzylsulfonyl macroheterocyclosiloxane content possessed composition-dependent properties, including thermal, surface, and mechanical characteristics. The copolymers also emitted blue fluorescence due to the clustering-triggered emission and luminescence of nonconventional luminogens. Ring-opening copolymerization (ROCP) of benzylsulfonyl macroheterocyclosiloxane (BSM) and five different cyclosiloxanes was systematically investigated. A general approach for the synthesis of benzylsulfonyl-containing silicone copolymers with various substituents, including methyl, vinyl, ethyl, and phenyl, was developed herein. A series of copolymers with variable incorporation (from 6 % to 82 %) of BSM were obtained by modifying the comonomer feed ratio and using KOH as the catalyst in a mixed solvent of dimethylformamide and toluene. The obtained copolymers exhibited various composition-dependent properties and unique viscoelasticity. Notably, the surface and fluorescent characteristics as well as the glass transition temperatures of the copolymers could be tailored by varying the amount of BSM. Unlike typical sulfone-containing polymers, such as poly(olefin sulfone)s, the prepared copolymers displayed excellent thermal and hydrolytic stability. The universal strategy developed in the present study provides a platform for the design of innovative silicone copolymers with adjustable structures and performance.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF POLYMER SCIENCE
·
2020
·Vol. 58
·期 15
·2108-2115
·
IF 0
Rui Feng,Suyun Jie,Pierre Braunstein,Bo-Geng Li
The ring-opening copolymerization of ε-caprolactone and δ-valerolactone was carried out under solvent-free conditions with a pyridyl-urea ( 6C-PU )/7-methyl-1,5,7-triazabicyclo[4.4.0]dec-5-ene catalytic system by premixing two monomers, yielding gradient copolyesters with cyclic and linear structures in the absence or presence of an initiator, respectively. The random and block copolyesters of these two monomers were also prepared for comparison. The results of 1 H and 13 C NMR spectra determined the linear and cyclic structure of copolymers. The kinetic experiment was used to determine the consuming rates of two monomers during the polymerization. The topologies and thermal properties of all the copolymers were characterized and compared by NMR and DSC. Graphical Gradient copolymers with cyclic and linear topologies have been prepared via the ring-opening copolymerization of ε-caprolactone and δ-valerolactone in the absence or presence of BnOH catalyzed by a pyridyl-urea ( 6C-PU )/7-methyl-1,5,7-triazabicyclo[4.4.0]dec-5-ene system. The structure and thermal properties of copolymers with different composition or different sequential distribution were also investigated.
研究领域:
高分子化学
·
材料科学
✓ 已验证
DOI
POLYMER
·
2012
·
IF 3.438
Na Qiang,Weihong Yang,Longfei Li,Peng Dong,Jixiang Zhu,Tao Wang,Chenguang Zeng,Daping Quan
abstract Nano-fibrous scaffolds modified with biological peptides, which can mimic the physical and chemical characteristics of an extracellular matrix (ECM), have been considered good candidate matrices for cell culture in tissue engineering application. In this study, a series of semicrystalline block copolymers, specifically pendent carboxyl-containing poly( ε -caprolactone- co - β -malic acid)-block-poly( l -lactide), were synthesized to fabricate nano-fibrous scaffolds via thermal induced liquid–liquid phase separation process. Random prepolymers P(CL- co -BMD) were first synthesized through ring-opening copolymerization of ε-CL and 3(S)-[(benzyloxycarbony)methyl]-1,4-dioxane-2,5-dione (BMD) in the presence of dodecanol as initiator and stannous octoate(Sn(Oct) 2 ) as catalyst. The terminal hydroxyl of P(CL- co -BMD)-OH was subsequently added to initiate the ring-opening of l -LA catalyzed by Sn(Oct) 2 . After deprotection, a series of block copolymers, poly( ε -caprolactone- co - β -malic acid)-block-poly( l -lactide)(PCM- b -P L LA), were obtained and fabricated into nanofibrous scaffolds through thermally induced phase separation (TIPS) technique using tetrahydrofuran (THF) as solvent at a gelation temperature of −40 °C. The structure of the copolymers was characterized Nuclear Magnetic Resonance ( 1 H NMR, 13 C NMR), Gel Permeation Chromatography (GPC), and Differential Scanning Calorimetry (DSC). The crystallinity of the PCL segment generally decreased when the amount of BMD segment in P(CL- co -BMD) was increased. However, for PCM- b -P L LA, aside from the crystal melting peak of P L LA at 170 °C–180 °C, no indication of PCL section crystallization occurred because the crystallization of the PCL segment was interrupted by PLLA segment. The nanofiber size of the matrices was in the range of 180 nm–650 nm, similar to the architecture of ECM at the nanometer scale. These nanofibrous matrices have design potential to conjugate covalently to bioactive molecules for tissue engineering.
研究领域:
高分子化学
·
材料科学
·
生物医学工程
·
纳米技术
·
组织工程
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2025
·
IF 8.2
Xingshuang Lv,Zhi Li,Haojia Wei,Shuaishuai Yuan,Xiaohui Fu,Zhibo Li
The synthesis and optimization of antibacterial agents for thermoplastic polyurethane (TPU) matrices is highly imperative for the development of antibacterial TPUs, especially for applications in biomedical devices. Macromolecular or polymer-based antimicrobials are extremely appealing for their environmental compatibility, low toxicity toward host cells, and low-leachable characteristic, making them ideal additives for antibacterial materials. Herein, quaternary ammonium salt (QAS)-containing copolyesters of P(MBL-N+-CL) were designed and synthesized as polymeric antimicrobials via ring-opening copolymerization (ROCP) of α-methylene-γ-butyrolactone (MBL) and ε-caprolactone (ε-CL) followed by selective post-functionalization via the thiol–ene “click” reaction to introduce cationic moieties. Owing to the flexibility of the synthetic routes, the density and distribution of QAS groups can be conveniently tuned by adjusting the content and functionality of pendent vinyl groups, giving an efficient immobilization strategy for the preparation of antibacterial modifiers. Commercial TPU Estane 58277 was then physically blended with the cationic P(MBL-N+-CL)s (∼9 wt %) to prepare a series of P(MBL-N+-CL)/TPU composite films via the solvent casting method. It was found that the addition of cationic P(MBL-N+-CL) did not alter the basic physical properties of TPU but showed much lower leachability and hemolysis ratio than that of TPU blends with a small molecular QAS additive. Particularly, P(MBL-N+-CL)-3/TPU with 1.5 wt % QAS units showed almost 100% contact-bactericidal rate against Staphylococcus aureus (S. aureus), and such effects were still maintained after 10 cycles of surface washing. The influence of different P(MBL-N+-CL) additives on surface, thermal, and mechanical properties and cytotoxicity was systematically investigated. The results revealed that the hydrophilicity of the TPU films improved after blending with P(MBL-N+-CL) due to the hydration of QAS units. The thermal stability of the composite films was almost maintained with a degradation temperature of 5% mass loss (Td,5%) above 310 °C and the elasticity was improved, but the tensile strength slightly decreased. The high antibacterial activity, low leachability, negligible hemolytic activities, and low cytotoxicity endow these optimized antibacterial TPU composite films with great potential applications in various medical devices.
研究领域:
材料科学
·
高分子化学
·
生物医学工程
·
抗菌材料
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Polymer Chemistry
·
2016
·Vol. 7
·期 41
·6297-6308
·
IF 5.687
Xin Wang,Jiaqi Liu,Songquan Xu,Jiaxi Xu,Xianfu Pan,Jingjing Liu,Saide Cui,Zhenjiang Li,Kai Guo
Catalytic ring-opening polymerization (ROP) of the three major types of cyclic monomers, lactides, lactones, and carbonates, showed match and mismatch between the monomer and the catalyst. Therefore, one organocatalyst that works for all of the three in ROPs by a controlled/living nature is rare in ROPs. Herein, we proposed a traceless switch organocatalysis (TSOC) strategy and demonstrated it by switching from a Brønsted acid cationic to base/conjugate-acid bifunctional mechanisms in ROPs. Ring-opening copolymerization (ROCOP) of different types of monomers of lactones to lactides, and carbonates to lactides by organocatalysis was realized through an acid plus a base, i.e. “one plus one”, approach in one pot. The TSOC was exemplified by a methanesulfonic acid (MSA)/8-diazabicyclo[5.4.0]undec-7-ene (DBU) pair, and by diphenylphosphate (DPP)/DBU pair catalysis. DPP catalyzed cationic ROPs of δ-valerolactone (VL) and trimethylene carbonate (TMC); orthogonally, “DPP plus DBU” switched it into DPP/2DBU catalyzed bifunctional ROPs of L-lactide (LA), producing sequences of PVL-b-PLA, and PVL-b-PTMC-b-PLA. Alternatively, MSA catalyzed cationic ROPs of ε-caprolactone (CL) and TMC; switching it into MSA/2DBU catalyzed ROPs afforded block copolymers of PCL-b-PLA and PCL-b-PTMC-b-PLA. All the di- and triblock copolymers were characterized using 1H NMR, 13C NMR, and SEC; each showed its exact sequence length, predicted molecular weight, and narrow dispersity. An ROCOP of the three major types of carbonyl-containing cyclic monomers using a single organocatalysis platform, in one pot, via a traceless switch, and through multi-feeding of the monomers, to sequence controlled multiblock copolymers was fulfilled.
研究领域:
有机化学
·
高分子科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Nature Synthesis
·
2025
·
IF 20
Feng Ximin,Liu Xiong,Zhang Xun,Guo Wenqi,Zhang Chengjian,Zhang Xinghong
The need for sustainable alternatives to petroleum-based polymers has driven the development of advanced catalysts for polyester synthesis. Here we present a series of covalently tethered borane–oxyanion organocatalysts for the ring-opening copolymerization of epoxides and cyclic anhydrides. These catalysts achieve outstanding efficiency, with turnover frequencies up to 13,500 h −1 and high molecular weights ( M n ) up to 174.0 kDa of the resultant polymers. Mechanistic studies reveal that intramolecular cooperation between borane and propagating species accelerates the rate-limiting epoxide ring-opening step, resulting in nearly equivalent energy barriers for epoxide and anhydride ring opening. Notably, the covalent tethering strategy not only enhances performance but also imparts remarkable air stability, addressing key limitations of conventional borane-based catalysts. Furthermore, our catalysts exhibit broad substrate scope and high thermal stability, facilitating the production of metal-free polyesters with tailored characteristics. This work establishes a sustainable and robust platform for polyester synthesis, with promising applications in biomaterials and packaging.
研究领域:
高分子化学
·
有机催化
·
可持续材料
·
高分子工程
✓ 已验证
产品关联
DOI
高影响因子
POLYMER
·
2017
·
IF 3.684
Hongjun Yang,Aibin Sun,Chenqun Chai,Wenyan Huang,Xiaoqiang Xue,Jianhai Chen,Bibiao Jiang
Aliphatic polyesters have been widely used in environmental and biomedical engineering, but a lack of functional groups limits their applications. Here, we reported a facile approach to synthesize vinyl functional polyester via the ring opening copolymerization of ε-caprolactone (CL) and allyl glycidyl ether (AGE). NMR analysis confirmed the copolymeric structures and suggested that the copolymerization depended on the epoxide ring of AGE rather than vinyl group. The amount of AGE incorporated into the copolymers ( F AGE ) increased with the amount of epoxide monomer feed with a maximum incorporation of 16.7%. Increasing temperature helped AGE to incorporate into the copolymer, however, accompanying with lots amount of AGE homopolymers . The resulting copolymer was successfully post-functionalized by thiol-end click, epoxidation , and bromination reactions depending on the reactivity of pendent ally groups. This facile and efficient approach can be used to functionalize biodegradable polymers and synthesize some new polymers under mild conditions.
研究领域:
材料科学
·
高分子化学
·
生物医学工程
·
环境工程
✓ 已验证
产品关联
DOI
高影响因子
MACROMOLECULAR BIOSCIENCE
·
2014
·Vol. 14
·期 10
·1429-1436
·
IF 3.65
Dongming Xing,Lie Ma,Changyou Gao
Maleimide-functionalized poly(ester carbonate)s are synthesized by ring-opening copolymerization of furan–maleimide functionalized trimethylene carbonate (FMTMC) with L -lactide and a subsequent retro Diels-Alder reaction. The maleimide groups on poly(ester carbonate)s are amenable to Michael addition with thiol-containing molecules such as 3-mercapto-1-propanol, 2-aminoethanethiol hydrochloride, and mercaptoacetic acid under mild conditions, enabling the formation of biodegradable materials with various functional groups (e.g., hydroxyl, amine, and carboxyl). In particular, the maleimide-functionalized poly(ester carbonate) is clicked with a laminin-derived peptide CQAASIKVAV. In vitro culture of PC12 cells shows that the maleimide-functionalized polymers, especially the CQAASIKVAV-grafted one, could support cell proliferation and neurite outgrowth. The maleimide-functionalized poly(ester carbonate)s provide a versatile platform for diverse functionalization and have comprehensive potential in biomedical engineering.
研究领域:
材料科学
·
生物医学工程
·
高分子化学
·
细胞生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）