INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2021
·
IF 3.764
Minglei Li,Yaheng Zhang,Jie Zhang,Min Peng,Liuming Yan,Zhiyong Tang,Qing Wu
Gas–liquid–solid (G–L–S) three-phase slug flow provides an efficient pathway to utilize solid catalysts in continuous flow and was adopted in the mesoporous graphite carbon nitride (mpg-C3N4)-catalyzed photoinduced electron/energy transfer reversible addition–fragmentation chain transfer (PET-RAFT) polymerization of methyl methacrylate (MMA) in this work. Kinetic studies and chain extension experiments illustrated the realization of reversible deactivation radical polymerization (RDRP) and the “easy to scale up” advantage of a continuous-flow reactor as compared to its batch counterpart. The light intensity played an important role on the PET-RAFT polymerization. An increasing amount of photocatalyst favored the monomer conversion within a limited range due to higher light blockage, and the monomer conversion reached a stable level at a lower catalyst concentration when higher light power was applied. When compared with fully continuous flow, the G–L–S slug flow was beneficial to the PET-RAFT polymerization due to the intensified swirling strength and narrower velocity field. Decreasing the gas-to-slurry ratio also led to narrower velocity distribution, which favored the polymerization as well. Moreover, the polymerization rates remained stable in multiple recycles, demonstrating that the present G–L–S slug flow was a reliable and easy processing approach for utilizing the solid catalyst.
研究领域:
化学工程
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高分子化学
·
催化科学
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DOI
高影响因子
JOURNAL OF POLYMER RESEARCH
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2021
·Vol. 28
·期 4
·1-9
·
IF 3.097
Ding Mei,Zhang Xiuzhi,Mi Xiangyun,Zhang Ming,Guo Wenjuan,Pei Meishan
Comb-like polycarbonate superplasticizers (PCEs) are widely used as a cement additive, and obtaining high-performance PCEs has become a hot topic. PCEs are usually kind of random polymers obtained by free radical solution polymerization, and thus it is hard to clarify the relationship between the properties of PCE and its structure. In this work, the block copolymers PCEs with the clear structure were synthesized by the reversible addition-fragmentation chain transfer (RAFT) polymerization. The relationship between the structure of PCE and its dispersion properties in cement was systematically discussed based on the flowability data of the cement paste with PCEs and the adsorption data of PCEs on the cement particles. Effects of the monomer ratio and the molecular weight on the adsorption and dispersion ability of PCEs in cement paste were studied. The results showed that the adsorption capacity and dispersion properties of PCEs in cement paste are related to the structural parameters of the polymer molecules. PCEs exhibited the optimal dispersion properties when the ratio of the monomers was 6:1 and the molecular weight was no greater than PCE-8 ( M n = 53,450, M w = 62,358).
研究领域:
材料科学
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化学工程
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DOI
高影响因子
FIBERS AND POLYMERS
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2021
·Vol. 23
·期 2
·396-403
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IF 2.153
Meng Xu,Dong Yanyan,Arias Manuel J. Lis,Mu Song,Liang Liping
For the actual courses of surroundings conservation, segregation of oily water mixtures is increasingly desired. The hydrophobic/oleophilic cotton fabric as a system for removing oil from a water phase was prepared by reversible addition fragmentation chain transfer (RAFT) reaction technology. A piece of fabric was modified with the RAFT chain transfer agent S-1-Dodecyl-S′-(α′,α″-dimethyl-α″-acetic acid) trithiocarbonate (CTA), then hydrophobic/oleophilic interface was fabricated on the CTA modified fabric by grafting the octadecyl methacrylate. The chemical structures, surface topographies and surface properties were characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and contact angle experiments, respectively. The ability of as-prepared fabric with a separation efficiency was better than 97.0 % on average for various types of oil/water mixtures demonstrated the hydrophobic/oleophilic property. We believe that the work will extend the applications of fabric in the oil/water separation and provide a new design in practical applications.
研究领域:
材料科学
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环境工程
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化学工程
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DOI
高影响因子
APPLIED SURFACE SCIENCE
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2015
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IF 2.711
Yingge Shi,Meiying Liu,Ke Wang,Hongye Huang,Qing Wan,Lei Tao,Lihua Fu,Xiaoyong Zhang,Yen Wei
Nanodiamond (ND) is a novel class of carbon nanomaterials, which has been extensively investigated for biomedical applications because of its small size, high surface area and excellent biocompatibility. However, the biomedical applications of unmodified ND are still largely restricted because of their poor dispersibility in both aqueous and organic medium. In this work, we reported a novel strategy for the surface modification of ND via reversible addition fragmentation chain transfer (RAFT) polymerization. For preparation of the PEGylated ND (pPEGMA-ND), chain transfer agent (CTA) was immobilized onto ND through reaction between the hydroxyl group of ND and the carboxyl group of CTA, which was used as the initiator for surface-initiated RAFT polymerization. The successful preparation of pPEGMA-ND was characterized by nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectra and thermal gravimetric analysis in detail. Results demonstrated that pPEGMA-ND exhibited enhanced water dispersibility and desirable biocompatibility, making it promising for biomedical applications.
研究领域:
材料科学
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生物医学工程
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化学
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DOI
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 24
·18922-18931
·
IF 3.84
Jianbo Tan,Xin Rao,Jianwen Yang,Zhaohua Zeng
Cross-linked PMMA microspheres have been synthesized by photoinitiated RAFT dispersion polymerization with dipropylene glycol diacrylate (DPGDA) or trimethylolpropane triacrylate (TMPTA) as the cross-linker. Monodisperse microspheres were obtained in the presence of 0.5 wt% S,S′-bis(α,α′-dimethyl-α′′-acetic acid) trithiocarbonate (BDMAT, a RAFT agent) with DPGDA concentration up to 5 wt% or TMPTA concentration up to 2 wt%. The particle formation process was investigated, and the results reveal that the cross-linking reaction was retarded to a certain extent by the RAFT process, which is crucial for the formation of uniform particles under high cross-linker concentrations. The phase diagrams for the methodology have been built up, and show that the procedure could only give polydisperse microspheres at a low DPGDA concentration or coagulum at a high DPGDA concentration in the absence of a RAFT agent, and monodisperse microspheres were obtained at DPGDA concentration up to 5 wt% when the RAFT agent concentration reached an appropriately high level, e.g. 0.5 wt% BDMAT or 0.75 wt% DDMAT. By adjusting the reaction conditions, we have prepared monodisperse cross-linked PMMA microspheres with 10 wt% DPGDA added at the beginning of the reaction. Furthermore, we have functionalized the cross-linked microspheres by adding a functional comonomer to the system at the beginning of polymerization, or by surface-initiated RAFT polymerization via the RAFT groups attached on the particle surface.
研究领域:
材料科学
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高分子化学
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纳米技术
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产品关联
DOI
高影响因子
Polymer Chemistry
·
2025
·
IF 3.9
Nan Qin,Na Li,Xiang Gao
Photoacid generators (PAGs) play an important role in chemically amplified resists (CARs), but small molecule PAGs have low solubility and limited compatibility with resins, which may lead to various problems. One of the important solutions is to bound PAG to polymer chains but differences in monomer reactivity can lead to an uneven distribution of molecular chain sequences between different polymer chains during polymerization, potentially impacting the lithographic performance. In this work, PAG units were incorporated into the photoresist resin polymer backbone via reversible addition-fragmentation chain transfer (RAFT) polymerization to synthesize methyl methacrylate polymer with different PAG loadings. The lithographic properties of the PAG bound polymer resist and the PAG blend polymer resist were studied and compared. The direct incorporation of PAG functionality into the polymer showed lower sensitivity, shorter acid diffusion length, and better compatibility. By observing the lithography results through AFM and SEM, the lithography lines of the PAG bound polymer photoresist synthesized via RAFT polymerization exhibited improved morphology and narrower line edge roughness (LER).
研究领域:
材料科学
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化学工程
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产品关联
DOI
高影响因子
Polymer Chemistry
·
2025
·
IF 3.9
Jiayi Zhang,Ruyue Cao,Xiaowei Wang,Yixuan Wang,Anchao Feng
This study introduces a novel approach combining reversible addition–fragmentation chain transfer (RAFT) polymerization and hetero-Diels–Alder (HDA) reactions to efficiently synthesize hyperbranched polymers (HBPs) with controlled topology. The traditional ABn monomer methods for creating HBPs face limitations due to random polymerization and the risk of gelation. By optimizing the ABn system into an ABx macromonomer framework, this new RAFT–HDA method enables controlled polymerization, reducing intramolecular cyclization and topological defects and broadening the range of possible polymer architectures. Additionally, more readily available and widely used novel dienes and dienophiles have been identified for the HDA reaction. The versatility of this approach was demonstrated by synthesizing a variety of HBPs with different branching degrees and molecular weights, which were thoroughly characterized by NMR, FTIR, GPC, and DLS techniques. This study provides a robust and efficient pathway for synthesizing complex polymer structures, demonstrating that the RAFT–HDA strategy enables the production of well-defined hyperbranched polymers with significant potential for applications in nanomaterials, biomedicine, and advanced functional materials.
研究领域:
材料科学
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化学工程
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产品关联
DOI
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 41
·34659-34665
·
IF 3.289
Chun Tian,Tianchi Xu,Lifen Zhang,Zhenping Cheng,Xiulin Zhu
Phosphorus-containing polymers have been found wide applications in many fields. In this work, a new kind of phosphorus-containing monomer with α-hydroxy phosphonate 4-((diethoxyphosphoryl)(hydroxy)methyl)phenyl methacrylate (PHMA) was firstly synthesized, and then copolymerization of PHMA and methyl methacrylate (MMA) was carried out via reversible addition–fragmentation chain transfer (RAFT) polymerization. The copolymerization kinetics and successful chain-extension reaction using the resultant PPHMA-co-PMMA confirmed the features of “living”/controlled radical polymerization. According to the thermal gravimetric analyzer (TGA) test, the thermal stability of the resultant phosphorus-containing copolymers increased significantly compared to the conventional methacrylate polymer materials due to the attachment of the phosphonate groups into the side chain of the copolymers. In addition, its superior flame-retardant performance was verified by the micro-scale combustion calorimetry (MCC) test. Meanwhile, the hydrophilicity of the phosphorus-containing copolymers was reflected by water contact angle measurement.
研究领域:
材料科学
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高分子化学
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DOI
高影响因子
Polymer Chemistry
·
2020
·Vol. 11
·期 47
·7542-7550
·
IF 5.342
Haoyu Liu,Sen Zhang,Xiaoyu Huang,Aishun Ding,Guolin Lu
A new acrylamide monomer consisting of both difluoromethylthio and isopropylamide moieties, N-3-(difluoromethylthio)propyl-N-(3-(isopropylamino)-3-oxopropyl)acrylamide (DFTP-NIPAM-AM), was firstly synthesized from 3-difluorothiomethyl-1-propylamine via aza-Michael addition reaction followed by amidation with acryloyl chloride. A well-defined fluoropolymer with a relatively narrow molecular weight distribution, poly(DFTP-NIPAM-AM), was obtained via reversible addition–fragmentation chain transfer (RAFT) polymerization using 3-(benzylthiocarbonothioylthio)propanoic acid as chain transfer agent. The thermal property of the poly(DFTP-NIPAM-AM) homopolymer was examined by differential scanning calorimetry (DSC), which indicated that difluoromethylthio moiety has an obvious impact on the glass transition temperature (Tg). The critical micelle concentration (cmc) of poly(DFTP-NIPAM-AM) homopolymer in aqueous solution was determined by fluorescent probe technique. It was found that poly(DFTP-NIPAM-AM) homopolymer could self-assemble into spherical micelles in aqueous solution, which was visualized by transmission electron microscopy (TEM).
研究领域:
高分子化学
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材料科学
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DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2022
·Vol. 139
·期 43
·e53061
·
IF 3.057
Binglun Gao,Lianwei Sun,Xin Chen,Xiaobo Zhai,Junchi Zheng,Xin Ye,Jianmin Lu,Anchao Feng,Liqun Zhang
The focus of this paper is to report the quantitative synthesis of bis-epoxy end functionalized polyisoprene (BETPI) macromonomers by anionic polymerization and reversible addition fragmentation chain transfer (RAFT) polymerization. For anionic polymerization, more stable and sterically hindered living anions polyisoprene (Li + -PIp-Li + ) react with epichlorohydrin (ECH) for the synthesis of well-defined BETPI. For the high-pressure RAFT polymerization, a novel bis-epoxy end functionalized trithiocarbonate (BODAAT) is designed as RAFT agent for the polymerization of isoprene monomer to obtain well-defined BETPI. The functionalities of the resulting BETPI are analyzed by Fourier transform infrared spectroscopy (FT-IR), NMR, and size exclusion chromatography (SEC). Through two polymerization methods, the BETPI with 600–1000 Da of molecular weight and over 75% of epoxy end capping rate is obtained, which can be further utilized as highly reactive liquid macromonomers.
研究领域:
高分子化学
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材料科学
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产品关联
DOI
高影响因子
EUROPEAN POLYMER JOURNAL
·
2021
·
IF 4.598
Suyan He,Li Xiao,Luminita Marin,Yike Bai,Xinjian Cheng
The development of water-soluble polymer dyes is of great practical and scientific significance. In this article, small fluorescent molecule boron-dipyrromethene (BODIPY) bearing C=C bond was synthesized first. And then, via Suzuki reaction, recognition groups were introduced into the 2, 6 positions of BODIPY. Thus polymerizable fluorescent monomers were prepared. Finally, methacrylic acid (MAA) was copolymerized with the as-prepared small molecular fluorescent monomers via reversible addition-fragmentation chain transfer (RAFT) polymerization methodology. Four fully-water-soluble polymer sensors with BODIPY moieties in the end of the polymer chain were obtained eventually. In the presence of long PMAA chain, and by the assistance of it, BODIPY could be dissolved totally in water. These polymer sensors exhibited sensitive and selective recognition ability to Fe 3+ . Even the content rate of BODIPY was as low as 0.5% of the polymer (calculated from element analysis), the detection limit could reach 1.2 μM. The sensors with two recognition groups in one BODIPY unit were more sensitive than that with one recognition groups in each BODIPY unit. The sensing mechanism was investigated as well. By endowing the water solubility to organic sensors, the application scope could be greatly enlarged in sensing metal ions in aqueous environments. This work provides a method to develop water soluble high performance polymer sensors.
研究领域:
材料科学
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化学传感器
·
分析化学
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产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2025
·
IF 2.8
Yanan Chao,Xinde Tang,Fei Ma,Xinyan Wang,Ruixin Fu,Xuanjie Zheng,Zihao Tang,Laixue Pang,Yong Yang,Fuying Dong
Clay rapidly adsorbs polycarboxylate superplasticizers (PCEs), reducing effective dispersant concentration in cement slurries. In this work, using ethylene glycol monovinyl polyethylene glycol ether (EPEG) and acrylic acid (AA) as the main raw materials, three cationic functional PCEs (RPCEs: RPCE-A, RPCE-D, RPCE-S) with enhanced clay tolerance were prepared via reversible addition-fragmentation chain transfer (RAFT) polymerization. These PCEs were characterized by FTIR, 1 H NMR, and GPC. The polydispersity index of RPCEs (1.24–1.27) indicated the character of living/controlled polymerization. Compared with the conventional PCEs, RPCEs can significantly enhance the fluidity of cement paste, and the fluidity retention can reach fine stability even when the clay occupies 0.5 wt.% of cement. X-ray diffraction and fluidity analysis show that, unlike the conventional PCEs, RPCEs can enter the clay layers through side-chain intercalation and ion exchange, resulting in an increase in layer spacing. This approach can open an avenue for broadening the application and increasing the adaptability of PCEs.
研究领域:
材料科学
·
高分子化学
·
土木工程
·
应用化学
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）