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In-situ forming ultra-mechanically sensitive materials for high-sensitivity stretchable fiber strain sensors

National science Review 2024年第6期11卷 254-263页

作者： Rouhui Yu Changxian Wang Xiangheng Du Xiaowen Bai Yongzhong Tong Huifang Chen Xuemei Sun Jing Yang Naoji Matsuhisa Huisheng Peng Meifang Zhu Shaowu Pan State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and Engineering Donghua University MOE Key Lab of Disaster Forecast and Control in Engineering School of Mechanics and Construction Engineering Jinan University State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular Science and Institute of Fiber Materials and Devices Fudan University Department of Cardiology Shanghai Xuhui Central HospitalZhongshan-Xuhui Hospital Fudan University Research Center for Advanced Science and Technology and Institute of Industrial Science The University of Tokyo

Fiber electronics with flexible and weavable features can be easily integrated into textiles for wearable applications. However, due to small sizes and curved surfaces of fiber materials, it remains challenging to load robust active layers, thus hindering production of high-sensitivity fiber strain sensors. Herein, functional sensing materials are firmly anchored on the fiber surface in-situ through a hydrolytic condensation *** anchoring sensing layer with robust interfacial adhesion is ultra-mechanically sensitive, which significantly improves the sensitivity of strain sensors due to the easy generation of microcracks during stretching. The resulting stretchable fiber sensors simultaneously possess an ultra-low strain detection limit of 0.05%, a high stretchability of 100%, and a high gauge factor of 433.6, giving 254-folds enhancement in sensitivity. Additionally, these fiber sensors are soft and lightweight, enabling them to be attached onto skin or woven into clothes for recording physiological signals, e.g. pulse wave velocity has been effectively obtained by them. As a demonstration, a fiber sensor-based wearable smart healthcare system is designed to monitor and transmit health status for timely intervention. This work presents an effective strategy for developing high-performance fiber strain sensors as well as other stretchable electronic devices.

关键词： fiber strain sensor stretchable wearable healthcare

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Conformational Disorder Within the Crystalline Region of Silica-Filled Polydimethylsiloxane:A Solid-State NMR Study

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Chinese Journal of polymer science 2024年第11期42卷 1780-1792,I0012页

作者： Yu-Qi Xiong Chang-Lin Li Ai Lu Liang-Bin Li Wei Chen National Synchrotron Radiation Laboratory Anhui Provincial Engineering Laboratory of Advanced Functional Polymer FilmCAS Key Laboratory of Soft Matter ChemistryUniversity of Science and Technology of ChinaHefei230026China Department of Accelerator Science and Engineering Physics School of Nuclear Science and TechnologyUniversity of Science and Technology of ChinaHefei230026China Institute of Chemical Materials China Academy of Engineering PhysicsMianyang621900China

The crystallization behavior of silica-filled polydimethylsiloxane(PDMS)was investigated in detail by^(1)H solid-state nuclear magnetic resonance(^(1)H SS-NMR)in combination with synchrotron radiation wide-angle X-ray scattering(WAXS),and temperature-modulated differential scanning calorimetry(TMDSC)*** neat PDMS,no apparent difference is observed for the crystallinity characterized by^(1)H SS-NMR and WAXS at low-temperature ***,upon filler addition,a 15%-35%lower difference in crystallinity is observed measured by^(1)H SS-NMR compared to *** origin of such mismatch was explored through multi-component structural,dynamics,and chain-order analysis of PDMS samples with different filler *** 1D integrated WAXS results of PDMS with different filler fractions at different temperatures show that the packing structure as well as crystal size basically remain unchanged,but as the filler fraction increases from 0 phr to 60 phr,the rigid component’s dynamics order parameter S_(r)obtained by^(1)H SS-NMR decreases from 0.70 to *** filler fraction-dependent crystallinity calculated based on S_(r)was compared with experimental values,revealing a behavior of decreasing order in the crystalline *** with the results of accelerated chain dynamics in crystalline region as reflected by T_(2)values,the molecular origin is attributed to the formation of CONDIS crystals,whose conformational order is lost but the position and orientation orders are *** hypothesis is further supported by the TMDSC results,where,as the filler fraction increases from 0 phr to 60 phr,the melting range widens from 8.77 K to 14.56 K,representing a growth of166%.In addition to previous reports related to the condition for forming CONDIS mesophase,i.e.,temperature,pressure,and stretching,the nano-sized filler could also introduce the local conformational disorder for chain packing.

关键词： Solid state NMR polymer nanocomposite CONDIS crystal Local chain order PDMS crystallization

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Self-limiting stacks of curvature-frustrated colloidal plates: Roles of intraparticle versus interparticle deformations

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Physical Review E 2024年第2期110卷 024602-024602页

作者： Kyle T. Sullivan Ryan C. Hayward Gregory M. Grason Department of Physics Department of Chemical and Biological Engineering Department of Polymer Science and Engineering

In geometrically frustrated assemblies local intersubunit misfits propagate to intra-assembly strain gradients, giving rise to anomalous self-limiting assembly thermodynamics. Here we use theory and coarse-grained simulation to study a recently developed class of “curvamer” particles, flexible shell-like particles that exhibit self-limiting assembly due to the build up of curvature deformation in cohesive stacks. To address a generic, yet poorly understood aspect of frustrated assembly, we introduce a model of curvamer assembly that incorporates both intraparticle shape deformation as well as compliance of interparticle cohesive gaps, an effect we can attribute to a finite range of attraction between particles. We show that the ratio of intraparticle (bending elasticity) to interparticle stiffness not only controls the regimes of self-limitation but also the nature of frustration propagation through curvamer stacks. We find a transition from uniformly bound, curvature-focusing stacks at small size to gap opened, uniformly curved stacks at large size is controlled by a dimensionless measure of inter- versus intracurvamer stiffness. The finite range of interparticle attraction determines the range of cohesion in stacks that are self-limiting, a prediction which is in strong agreement with numerical studies of our coarse-grained colloidal model. These predictions provide critical guidance for experimental realizations of frustrated particle systems designed to exhibit self-limitation at especially large multiparticle scales.

关键词： Aggregation Elastic deformation Self-assembly Soft colloids

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Correlating processing induced orientation with tensile properties for mass polymerized acrylonitrile butadiene styrene test specimens

RSC Applied Polymers

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RSC Applied polymers 2024年第6期2卷 1032-1042页

作者： Fernandez, E. Edeleva, M. Cardon, L. Centre for Polymer and Material Technologies Department of Materials Textile and Chemical Engineering Ghent University Gent 9000 Belgium Laboratory for Chemical Technology Department of Materials Textile and Chemical Engineering Ghent University Gent 9000 Belgium Centre for Textile Science and Engineering Department of Materials Textile and Chemical Engineering Ghent University Gent 9000 Belgium

In this research, we deal with the link between tensile properties and processing-related morphology variations for mass polymerized acrylonitrile butadiene styrene (mABS). The orientation of multi-core polybutadiene (PB) particles, which are intrinsic to mABS, is investigated regarding flow, shear and cooling changes during sample production. The effect of a different sample size and annealing on the tensile responses has been verified by considering ISO 527 1A and 1BA dog bone samples. For the thin 1BA bars, multiple injection velocities and cooling rates during injection molding have been tested to obtain a more pure correlation between morphology and tensile properties. To perform comparable tensile measurements using both types of dog bone samples, a testing method has been designed for which a relation is included between the sample gauge length and cross head velocity, enabling the comparison of elastic deformation for ISO 527 1A and 1BA mABS samples. Regarding the mABS part morphology, injection molded parts display a skin-shear-core gradient morphology with respect to the PB-particle size and orientation. Annealing of both types of injection molded samples successfully removes most flow-induced orientation of the rubber particles but also results in a change in PB morphology by dissolving a small fraction of the rubber into the SAN matrix, forming PB-nanoparticles. These small particles promote shear bands upon craze-based deformation and therefore positively contribute to the sample toughness. High flow-induced orientation within mABS parts causes a significantly increased tensile stiffness, strength and toughness along the flow direction. Irrespective of the PB orientation, tensile bars with a large surface roughness experience early failure, due to premature craze and crack initiation at the sample surface. © 2024 RSC.

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Ethane integration project—a study for Egyptian NGLs plants and their economics

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Journal of engineering and Applied science 2024年第1期71卷 1-18页

作者： Elzohairy, Hamdy R. Ahmed, Tamer S. El-Marsafy, Sahar M. Chemical Engineering Department Faculty of Engineering Cairo University Giza12613 Egypt New Cairo Egypt Environmental Engineering Program Zewail City of Science and Technology 6th of October City Giza12578 Egypt

For Egypt, ethane is a vital chemical precursor, with the potential to significantly attract financial resources and drive economic growth. Enhancing its added value necessitates efficient recovery of ethane before it enters the national grid without processing. This research investigates the technical and economic feasibility of integrating natural gas liquids (NGLs) from three Egyptian NGLs plants—South Western Desert NGLs (SWD NGLs), North Western Desert NGLs (NWD NGLs), and East Mediterranean NGLs (EMD NGLs)—to improve ethane recovery from natural gas fields. The study focuses on revamping these NGLs plants using various NGLs recovery techniques, conducting a comprehensive comparison to identify the most effective methods for processing rich feed gas. Detailed design of the NGLs recovery processes was developed using HYSYS V.14 simulation software and supplementary calculation sheets. The design criteria encompass both technical and economic parameters to ensure a holistic approach in meeting project requirements. Results indicate a significant increase in ethane recovery: 16% for SWD NGLs, 10% for NWD NGLs (A, B, C), and 85% for EMD NGLs. This improvement will boost ethane feedstock for petrochemical companies from 2000 ton/day to 3500 ton/day, enabling increased polyethylene production. Economic analysis for the base case shows an expected internal rate of return (IRR) of 26%, a net present value (NPV) of USD 73 million, and a payback period of approximately 3 years. Sensitivity analysis on product prices, feed gas prices, and total capital investment confirms the project’s economic viability, with all cases showing feasibility (IRR ≥ 15%) except when product prices fall below USD 225/ton for propane, USD 215/ton for liquefied petroleum gas (LPG), and USD 25/bbl for condensate. This study highlights the potential for enhanced ethane recovery, offering substantial economic benefits and supporting the growth of Egypt’s petrochemical industry. © The Author(s) 202

关键词： Ethane

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AutoTemplate: enhancing chemical reaction datasets for machine learning applications in organic chemistry

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Journal of Cheminformatics 2024年第1期16卷 1-16页

作者： Chen, Lung-Yi Li, Yi-Pei Department of Chemical Engineering National Taiwan University Taiwan International Graduate Program on Sustainable Chemical Science and Technology (TIGP-SCST)

Abstract: This paper presents AutoTemplate, an innovative data preprocessing protocol, addressing the crucial need for high-quality chemical reaction datasets in the realm of machine learning applications in organic chemistry. Recent advances in artificial intelligence have expanded the application of machine learning in chemistry, particularly in yield prediction, retrosynthesis, and reaction condition prediction. However, the effectiveness of these models hinges on the integrity of chemical reaction datasets, which are often plagued by inconsistencies like missing reactants, incorrect atom mappings, and outright erroneous reactions. AutoTemplate introduces a two-stage approach to refine these datasets. The first stage involves extracting meaningful reaction transformation rules and formulating generic reaction templates using a simplified SMARTS representation. This simplification broadens the applicability of templates across various chemical reactions. The second stage is template-guided reaction curation, where these templates are systematically applied to validate and correct the reaction data. This process effectively amends missing reactant information, rectifies atom-mapping errors, and eliminates incorrect data entries. A standout feature of AutoTemplate is its capability to concurrently identify and correct false chemical reactions. It operates on the premise that most reactions in datasets are accurate, using these as templates to guide the correction of flawed entries. The protocol demonstrates its efficacy across a range of chemical reactions, significantly enhancing dataset quality. This advancement provides a more robust foundation for developing reliable machine learning models in chemistry, thereby improving the accuracy of forward and retrosynthetic predictions. AutoTemplate marks a significant progression in the preprocessing of chemical reaction datasets, bridging a vital gap and facilitating more precise and efficient machine learning applicati

关键词： Atom-to-atom mapping Data preprocessing Reaction data curation Reaction template

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Insightful analysis of physical properties, kinetics, absorption capacity, and regeneration heat duty of monoethanolamine and N-methyl-4-piperidinol blended solvent in post-combustion carbon capture

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Environmental science and Pollution Research 2024年第40期31卷 52868-52885页

作者： Apaiyakul, Rattanaporn Khuenkaew, Wachiramon Sirirathomsud, Ornicha Boonprasop, Sutthichai Liu, Heilei Gao, Hongxia Liang, Zhiwu Tontiwachwuthikul, Paitoon Sema, Teerawat Petrochemistry and Polymer Science Program Faculty of Science Chulalongkorn University Pathumwan Bangkok10330 Thailand Department of Chemical Engineering Faculty of Engineering Mahidol University Nakhon Pathom73170 Thailand Department of Biotechnology Faculty of Science Mahidol University Bangkok10400 Thailand School of Chemistry and Chemical Engineering Beijing Institute of Technology Beijing100081 China Provincial Hunan Key Laboratory for Cost-Effective Utilization of Fossil Fuel Aimed at Reducing CO₂ Emissions College of Chemistry and Chemical Engineering Hunan University Changsha410082 China Faculty of Engineering and Applied Science University of Regina ReginaSKS4S 0A2 Canada Department of Chemical Technology Faculty of Science Chulalongkorn University Pathumwan Bangkok10330 Thailand

In this study, the high potential tertiary N-methyl-4-piperidinol or MPDL (0.25–1.00 M) was blended with 5 M monoethanolamine (MEA) to formulate 5.25–6.00 M MEA-MPDL solvent and compare with the benchmark 5 M MEA. It was found that the density and the Henry’s constant slightly decreased, while the viscosity increased as the MPDL concentration in the blend increased. Even though the equilibrium CO2-loaded viscosity considerably increased (by 34.3–40.2%) as the MPDL content increased, it was still in a great operating region of less than 10 mPa.s. Experimental overall reaction kinetics constant (kov) was well corresponding with the zwitterion mechanism of MEA and the base-catalyze hydration mechanism of MPDL based absorption kinetics model, with %AAD of 0.56%. Interestingly, an addition of MPDL into 5 M MEA slightly enhanced kov (1.2–3.3% increment) and considerably favored absorption capacity (13–31% elevation), and regeneration heat duty (28–47% reduction), respecting 5 M MEA. The proposed strategic blending can maintain the overall solvent reactivity at the same level of the benchmark, while obviously increase the absorption capacity and largely reduce the regeneration heat duty. This highly favors a solvent upgrading for the existing 5 M MEA based CO2 capture plant. According to the recent data, 5 M MEA + 1.00 M MPDL was suggested. Since the blend was formulated at high concentration, its corrosiveness should also be considered. Graphical abstract: (Figure presented.) © The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2024.

关键词： Carbon capture and utilization

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Tuning polymer Molecular Weight Distribution in Cationic RAFT polymerization by Mixing Chain Transfer Agents

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Chinese Journal of Chemistry 2023年第14期41卷 1684-1690页

作者： Miao Chen Jiajia Li Dong Xing Xiangqiang Pan Jian Zhu State and Local Joint Engineering Laboratory for Novel Functional Polymeric Materials Jiangsu Key Laboratory of Advanced Functional Polymer Design and ApplicationSuzhou Key Laboratory of Macromolecular Design and Precision SynthesisDepartment of Polymer Science and EngineeringCollege of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhouJiangsu215123 China

polymer dispersity (Đ) or molecular weight distribution (MWD) is a basic but vital parameter for the properties of polymeric materials. Developing new methodologies for controlling polymer MWD is emerging as a research hotspot. However, the methods to tune polymer MWD in cationic polymerization are still not well explored. Herein, we present a simple method to control the dispersity of poly(isobutyl vinyl ether) (PIBVE) by mixing two different chain transfer agents in batch visible light induced cationic RAFT polymerization. A broad dispersity range (Đ ≈ 1.16—1.80) was successfully achieved while maintaining monomodal MWD. Moreover, chain extension of PIBVE through both cationic polymerization and radical polymerization has been studied, which also provides a method to tune polymer MWD in mechanism transformation polymerization.

关键词： RAFT Photopolymerization Copolymers lonic polymerization Molecular weight distribution Dispersity

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Electromagnetic wave absorption performance and rheological behavior of rubber composites with low mass filling rate carbon nanofiber aerogel

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Journal of Materiomics 2024年第4期10卷 928-936页

作者： Zhiyi Zhang Bicheng Zhou Lan Jia Wenwen Yu Qiang Zheng College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan030024China Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering Taiyuan030000China rd Research Institute of China Electronics Technology Group Corporation Taiyuan030032China Department of Polymer Science&Engineering Zhejiang UniversityHangzhou310027China

With the development of electronic information science and technology,electromagnetic information security and electromagnetic pollution become more and more *** wave absorption(EMWA)rubber based on the absorbent of carbon with low density and good corrosion resistance is a kind of good EMWA materials for solving electromagnetic information security and electromagnetic *** this article,three-dimensional network structure carbon nanofiber aerogels(3DNSCAs)are prepared by vacuum annealing of three-dimensional network structure agarose/zinc acetate obtained by freeze-drying of agarose/zinc acetate *** EMWA rubber composites with 2.2%(in mass)3DNSCAs have almost the same density as silicone rubber(PDMS),and the dispersity of 3DNSCAs in PDMS is studied by rheological *** effective absorption bandwidth(EAB,frequency for reflection loss<–10 dB)of the 2 mm thick PDMS/C-800 is 4 GHz,and the minimum value of reflection loss(RL_(min))is−52 dB with the thickness of 3.5 *** PDMS/C-1000 with the thickness of 3.5 mm has an EAB up to 4.8 *** cross section(RCS)reduction of PDMS/C-800 can achieve 20 dB⋅m^(2) at the frequency of 6 GHz.

关键词： Electromagnetic wave absorption Rubber composite Carbon aerogel Rheological behavior Power loss density

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“1+1>2”:Highly efficient removal of organic pollutants by composite nanofibrous membrane based on the synergistic effect of adsorption and photocatalysis

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Journal of Materials science & Technology 2022年第29期124卷 76-85页

作者： Yuanting Xu Wanting Lin Dandan Yuan Shifan Chen Fang Li Yanping Long Chao He Weifeng Zhao Changsheng Zhao College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu 610065China Department of Polymer Science and Engineering Zhejiang UniversityHangzhou 310027China Med-X Center for Materials Sichuan UniversityChengdu 610041China College of Chemical Engineering Sichuan UniversityChengdu 610065China

Adsorption and photocatalysis are regarded as two desirable technologies for wastewater remediation,but are still unsatisfactory in removal effect,eco-friendly regeneration and facile *** this study,we developed a composite nanofibrous membrane material with excellent removal performance for organic pollutants based on synergistic adsorption and photocatalysis.A novel boron-doped,nitrogen-deficient graphitic carbon nitride(B-C3N4)photocatalyst as well as an amphiphilic copolymer of methyl methacrylate and acrylic acid(p(MMA-AA))were synthesized respectively,and then used to modify polyethersulfone for the fabrication of composite nanofibrous membrane with improved hydrophilicity,negativelycharge property and enhanced visible light response ***,the synergistic effect of adsorption and photocatalytic degradation for organic pollutants were identified especially and resulted in an excellent removal efficiency even superior to the combination of adsorption and photocatalytic degradation,which could be called a“1+1>2”*** addition,the regeneration and reusability,the purification ability for multicomponent wastewater,and the photocatalytic mechanism,were investigated and discussed *** this work,we not only prepared the nanofibrous membrane with synergistic effect of adsorption and photocatalysis,but also provided a versatile approach to design dualfunctional support material to ensure the practical applications of powdery photocatalyst in wastewater treatment.

关键词： Composite nanofibrous membrane material Wastewater remediation Photocatalytic degradation Adsorption Synergistic effect

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