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Recent Progresses in Synthesis of Cyclic Polymers in Large-scale and Some Functionalized Composites
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作者 QU Kairu GUO Lyuzhou +3 位作者 WANG Wenbin YAN Xuzhou CAO Xuezheng YANG Zhenzhong 《高等学校化学学报》 北大核心 2026年第1期42-57,共16页
Among various architectures of polymers,end-group-free rings have attracted growing interests due to their distinct physicochemical performances over the linear counterparts which are exemplified by reduced hydrodynam... Among various architectures of polymers,end-group-free rings have attracted growing interests due to their distinct physicochemical performances over the linear counterparts which are exemplified by reduced hydrodynamic size and slower degradation.It is key to develop facile methods to large-scale synthesis of polymer rings with tunable compositions and microstructures.Recent progresses in large-scale synthesis of polymer rings against single-chain dynamic nanoparticles,and the example applications in synchronous enhancing toughness and strength of polymer nanocomposites are summarized.Once there is the breakthrough in rational design and effective large-scale synthesis of polymer rings and their functional derivatives,a family of cyclic functional hybrids would be available,thus providing a new paradigm in developing polymer science and engineering. 展开更多
关键词 Cyclic polymer Large-scale synthesis Single-chain nanoparticle Performance Composite
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An Emerging Liquid‑Crystalline Conducting Polymer Thermoelectrics:Opportunities and Challenges
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作者 Zhenqiang Ye Mingdong Zhang +3 位作者 Junyang Deng Lirong Liang Chunyu Du Guangming Chen 《Nano-Micro Letters》 2026年第3期240-273,共34页
Thermoelectric(TE)materials,being capable of converting waste heat into electricity,are pivotal for sustainable energy solutions.Among emerging TE materials,organic TE materials,particularly conjugated polymers,are ga... Thermoelectric(TE)materials,being capable of converting waste heat into electricity,are pivotal for sustainable energy solutions.Among emerging TE materials,organic TE materials,particularly conjugated polymers,are gaining prominence due to their unique combination of mechanical flexibility,environmental compatibility,and solution-processable fabrication.A notable candidate in this field is poly(2,5-bis(3-alkylthiophen-2-yl)thieno[3,2-b]thiophene)(PBTTT),a liquid-crystalline conjugated polymer,with high charge carrier mobility and adaptability to melt-processing techniques.Recent advancements have propelled PBTTT’s figure of merit from below 0.1 to a remarkable 1.28 at 368 K,showcasing its potential for practical applications.This review systematically examines strategies to enhance PBTTT’s TE performance through doping(solution,vapor,and anion exchange doping),composite engineering,and aggregation state controlling.Recent key breakthroughs include ion exchange doping for stable charge modulation,multi-heterojunction architectures reducing thermal conductivity,and proton-coupled electron transfer doping for precise Fermi-level tuning.Despite great progress,challenges still persist in enhancing TE conversion efficiency,balancing or decoupling electrical conductivity,Seebeck coefficient and thermal conductivity,and leveraging melt-processing scalability of PBTTT.By bridging fundamental insights with applied research,this work provides a roadmap for advancing PBTTT-based TE materials toward efficient energy harvesting and wearable electronics. 展开更多
关键词 Thermoelectric materials polymer PBTTT LIQUID-CRYSTALLINE
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Advances in polymer-based hydrogel systems for adipose-derived mesenchymal stem cells toward bone regeneration
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作者 Nivetha Suresh Sundaravadhanan Lekhavadhani Nagarajan Selvamurugan 《World Journal of Orthopedics》 2026年第1期13-28,共16页
Bone regeneration for non-load-bearing defects remains a significant clinical challenge requiring advanced biomaterials and cellular strategies.Adiposederived mesenchymal stem cells(AD-MSCs)have garnered significant i... Bone regeneration for non-load-bearing defects remains a significant clinical challenge requiring advanced biomaterials and cellular strategies.Adiposederived mesenchymal stem cells(AD-MSCs)have garnered significant interest in bone tissue engineering(BTE)because of their abundant availability,minimally invasive harvesting procedures,and robust differentiation potential into osteogenic lineages.Unlike bone marrow-derived mesenchymal stem cells,AD-MSCs can be easily obtained in large quantities,making them appealing alternatives for therapeutic applications.This review explores hydrogels containing polymers,such as chitosan,collagen,gelatin,and hyaluronic acid,and their composites,tailored for BTE,and emphasizes the importance of these hydrogels as scaffolds for the delivery of AD-MSCs.Various hydrogel fabrication techniques and biocompatibility assessments are discussed,along with innovative modifications to enhance osteogenesis.This review also briefly outlines AD-MSC isolation methods and advanced embedding techniques for precise cell placement,such as direct encapsulation and three-dimensional bioprinting.We discuss the mechanisms of bone regeneration in the AD-MSC-laden hydrogels,including osteoinduction,vascularization,and extracellular matrix remodeling.We also review the preclinical and clinical applications of AD-MSC-hydrogel systems,emphasizing their success and limitations.In this review,we provide a comprehensive overview of AD-MSC-based hydrogel systems to guide the development of effective therapies for bone regeneration. 展开更多
关键词 Mesenchymal stem cells Adipose-derived mesenchymal stem cells Bone tissue engineering HYDROGELS Bone regeneration polymerS
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Lithium-Ion Dynamic Interface Engineering of Nano-Charged Composite Polymer Electrolytes for Solid-State Lithium-Metal Batteries
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作者 Shanshan Lv Jingwen Wang +7 位作者 Yuanming Zhai Yu Chen Jiarui Yang Zhiwei Zhu Rui Peng Xuewei Fu Wei Yang Yu Wang 《Nano-Micro Letters》 2026年第2期288-305,共18页
Composite polymer electrolytes(CPEs)offer a promising solution for all-solid-state lithium-metal batteries(ASSLMBs).However,conventional nanofillers with Lewis-acid-base surfaces make limited contribution to improving... Composite polymer electrolytes(CPEs)offer a promising solution for all-solid-state lithium-metal batteries(ASSLMBs).However,conventional nanofillers with Lewis-acid-base surfaces make limited contribution to improving the overall performance of CPEs due to their difficulty in achieving robust electrochemical and mechanical interfaces simultaneously.Here,by regulating the surface charge characteristics of halloysite nanotube(HNT),we propose a concept of lithium-ion dynamic interface(Li^(+)-DI)engineering in nano-charged CPE(NCCPE).Results show that the surface charge characteristics of HNTs fundamentally change the Li^(+)-DI,and thereof the mechanical and ion-conduction behaviors of the NCCPEs.Particularly,the HNTs with positively charged surface(HNTs+)lead to a higher Li^(+)transference number(0.86)than that of HNTs-(0.73),but a lower toughness(102.13 MJ m^(-3)for HNTs+and 159.69 MJ m^(-3)for HNTs-).Meanwhile,a strong interface compatibilization effect by Li^(+)is observed for especially the HNTs+-involved Li^(+)-DI,which improves the toughness by 2000%compared with the control.Moreover,HNTs+are more effective to weaken the Li^(+)-solvation strength and facilitate the formation of Li F-rich solid-electrolyte interphase of Li metal compared to HNTs-.The resultant Li|NCCPE|LiFePO4cell delivers a capacity of 144.9 m Ah g^(-1)after 400 cycles at 0.5 C and a capacity retention of 78.6%.This study provides deep insights into understanding the roles of surface charges of nanofillers in regulating the mechanical and electrochemical interfaces in ASSLMBs. 展开更多
关键词 Charged nanofillers Nanocomposite polymer electrolyte Dynamic lithium ion interface Solid ion-conductors Solidstate lithium-metal battery
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Metallized polymer current collector as“stress acceptor”for stable micron-sized silicon anodes 被引量:1
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作者 Ziyi Cao Haoteng Sun +7 位作者 Yi Zhang Lixia Yuan Yaqi Liao Haijin Ji Shuaipeng Hao Zhen Li Long Qie Yunhui Huang 《Journal of Energy Chemistry》 2025年第2期786-794,I0017,共10页
Micron-sized silicon(μSi)is a promising anode material for next-generation lithium-ion batteries due to its high specific capacity,low cost,and abundant reserves.However,the volume expansion that occurs during cyclin... Micron-sized silicon(μSi)is a promising anode material for next-generation lithium-ion batteries due to its high specific capacity,low cost,and abundant reserves.However,the volume expansion that occurs during cycling leads to the accumulation of undesirable stresses,resulting in pulverization of silicon microparticles and shortened lifespan of the batteries.Herein,a composite film of Cu-PET-Cu is proposed as the current collector(CC)forμSi anodes to replace the conventional Cu CC.Cu-PET-Cu CC is prepared by depositing Cu on both sides of a polyethylene terephthalate(PET)film.The PET layer promises good ductility of the film,permitting the Cu-PET-Cu CC to accommodate the volumetric changes of silicon microparticles and facilitates the stress release through ductile deformation.As a result,theμSi electrode with Cu-PET-Cu CC retains a high specific capacity of 2181 mA h g^(-1),whereas theμSi electrode with Cu CC(μSi/Cu)exhibits a specific capacity of 1285 mA h g^(-1)after 80 cycles.The stress relieving effect of CuPET-Cu was demonstrated by in-situ fiber optic stress monitoring and multi-physics simulations.This work proposes an effective stress relief strategy at the electrode level for the practical implementation ofμSi anodes. 展开更多
关键词 Micron-sized Si anodes Metallized polymer current collector Stress relieving Electrode design
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Preparation and Application of Polymer Silicate Phosphate Ferric Sulfate Used in High-Viscosity Oil Refining Wastewater Treatment 被引量:1
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作者 Xi CHEN Xinyang XU Yindi FAN 《Journal of Water Resource and Protection》 2009年第3期195-202,共8页
A new kind of flocculants, named Polymer Silicate Phosphate Ferric Sulfate(PSPFS), was synthesized by ferrous sulfate used as the main material and activated silicic acid as additive. In this paper, High-Viscosity Oil... A new kind of flocculants, named Polymer Silicate Phosphate Ferric Sulfate(PSPFS), was synthesized by ferrous sulfate used as the main material and activated silicic acid as additive. In this paper, High-Viscosity Oil Refining wastewater from Liaohe Petrochemical Corporation was the treatment object. Overall, the in-fluencing factors and synthesis technology conditions of PSPFS were determined by experiments. First of all, the conditions of influencing factors were showed as follows: the mass percent concentration of ferrous sulfate 55%,concentration of sodium silicate 15% , the molar ratio of ferrous sulfate and hydrogen peroxide 1.2:1, oxidation temperature 40 degree Celsius, oxidation time 4 hours, polymerization temperature 60 de-gree Celsius and polymerization time 2 hours. Secondly, the optimal ratios of components were determined by uniform design method. The molar ratio of Fe/Si is 5.0:1, Fe/H2SO4 is 3.2:1, and Fe/P is 18.0:1. At last, the optimal experimental condition was determined as follows: the dosing quantity 200mg/L, pH value 5.5~9, temperature 25~45℃, stirring time 2 min, and standing time 3 min, according to the result of floc-culation experiments with PSPFS. Besides, the result of the comparative experiments showed that the effi-ciency of PSPFS was much better than the reference flocculants. 展开更多
关键词 polymer silicate PHOSPHATE Ferric Sulfate FLOCCULANT PREPARATION High-Viscosity Oil Refining Wastewater
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Spider web-inspired structural design for an energy-dissipating polymer binder enabling stabilized silicon anodes
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作者 Xiangyu Lin Danna Ma +4 位作者 Ziming Zhu Shanshan Wang He Liu Xu Xu Zhaoshuang Li 《Journal of Energy Chemistry》 2025年第10期870-878,共9页
Silicon(Si)is considered one of the most promising anode materials for next-generation lithium-ion batteries due to its ultrahigh theoretical capacity.However,its application is significantly limited by severe volume ... Silicon(Si)is considered one of the most promising anode materials for next-generation lithium-ion batteries due to its ultrahigh theoretical capacity.However,its application is significantly limited by severe volume expansion,leading to structural degradation and poor cycling stability.Polymer binders play a critical role in addressing these issues by providing mechanical stabilization.Inspired by the mechanically adaptive architecture of spider webs,where stiff radial threads and extensible spiral threads act in synergy,a dual-thread architecture polymer binder(PALT)with energy dissipation ability enabled by integrating rigid and flexible domains is designed.The rigid poly(acrylic acid lithium)(PAALi)segments offer structural reinforcement,while the soft segments(poly(lipoic acid-tannic acid),LT)introduce dynamic covalent bonds and multiple hydrogen bonds that function as reversible sacrificial bonds,enhancing energy dissipation during cycling.Comprehensive experimental and computational analyses demonstrate effectively reduced stress concentration,improved structural integrity,and stable electrochemical performance over prolonged cycling.The silicon anode incorporating the PALT binder exhibits a satisfying capacity loss per cycle of 0.042% during 350 charge/discharge cycles at 3580 m A g^(-1).This work highlights a bioinspired binder design strategy that combines intrinsic rigidity with dynamic stress adaptability to advance the mechanical and electrochemical stability of silicon anodes. 展开更多
关键词 polymer binder Lithium-ion batteries silicon anodes Tannic acid
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Flocculation of flotation tailings in presence of silicate gel and polymer 被引量:5
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作者 YIN Zhi-gang Sultan Ahmed KHOSO +5 位作者 SUN Wei HU Yue-hua ZHAI Ji-hua GAO Yue-sheng ZHANG Chen-hu LIU Run-qing 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第8期1928-1937,共10页
Flotation tailings were successfully flocculated in the presence of cationic polyacrylamide and silica gel.The effects of various parameters such as polymer weight,charge density,and pH on the rate of flocculation wer... Flotation tailings were successfully flocculated in the presence of cationic polyacrylamide and silica gel.The effects of various parameters such as polymer weight,charge density,and pH on the rate of flocculation were also investigated in the current study.The flocculation mechanism of the flocculant on tailings was investigated using zeta potential and Fourier transform infrared(FTIR)measurements.The results obtained reveal that 1)sodium silicate gel,used as a binder for the consolidation of tailings form primary flocs,acts as an anchor and the adsorption of polymer flocculant on these anchors results in the formation of larger flocs and,consequently,enhanced settling rate;2)flocculation in the presence of silica gel and polymer has a faster settling rate than single-polymer flocculation owing to the mechanisms of charge neutralization and bridging as identified using zeta potential and FTIR measurements.A pilot level study was conducted to investigate the influence of processed water on the flotation of scheelite.The results show that the proposed tailing disposal method could improve scheelite recovery by 2%(approximately)and could reduce the daily operation costs of the plant by approximately 108.57 USD. 展开更多
关键词 silica gel polymer FLOCCULATION tailings disposal
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Synergistic Effect of Silicone Macromolecular Charring Agent and Ammonium Polyphosphate on Improving Flame Retardancy and Mechanical Properties of Ethylene-Butyl Acrylate Copolymer Composites
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作者 Xuan Huo Bingchen Wu +6 位作者 Yuanmeng Lou Junlin Zhu Cui Li Lili Ma Ye-Tang Pan Chuncheng Hao Xin Wen 《Journal of Polymer Materials》 2025年第2期517-530,共14页
Power cables are important pieces of equipment for energy transmission,but achieving a good balance between flame retardancy and mechanical properties of cable sheaths remains a challenge.In this work,a novel intumesc... Power cables are important pieces of equipment for energy transmission,but achieving a good balance between flame retardancy and mechanical properties of cable sheaths remains a challenge.In this work,a novel intumescent flame retardant(IFR)system containing silicone-containing macromolecular charring agent(Si-MCA)and ammonium polyphosphate(APP)was designed to synergistically improve the flame retardancy and mechanical properties of ethylene-butyl acrylate copolymer(EBA)composites.The optimal mass ratio of APP/Si-MCA was 3/1 in EBA composites(EBA/APP-Si-31),corresponding to the best flame retardancy with 31.2% of limited oxygen index(LOI),V-0 rating in UL-94 vertical burning test,and 76.4%reduction on the peak of heat release rate(PHRR)in cone calorimeter test.The enhancement mechanism was attributed to the synergistic effect of APP/Si-MCA during combustion,including the radical-trapping effect,the dilution effect of non-flammable gases,and the barrier effect of the intumescent char layer.Meanwhile,the tensile results indicated that EBA/APP-Si-31 also exhibited good mechanical properties with the addition of maleic anhydride-grafted polyethylene(PE-g-MA)as the compatibilizer.Thus,the APP/Si-MCA combination is an effective IFRs system for preparing high-performance EBA composites,and it will promote their applications as cable sheath materials. 展开更多
关键词 Ethylene-butyl acrylate copolymer intumescent flame retardants polymer composites synergistic effect cable sheath
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A thermo-associating copolymer integrated with biogenic nanosilica as a novel viscosifier in low solid drilling fluids
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作者 Alain Pierre Tchameni Robert Dery Nagre +5 位作者 Shu-Ming Yin Li-Qiang Wang Xiu-Ying Wang Si-Yuan Zhou Guan-Qun Hou Xu-Dong Wang 《Petroleum Science》 2025年第7期2884-2904,共21页
Smart low-solid drilling fluids(SLSDFs)with thermo-controllable rheological properties and attractive thickening characteristics have recently captivated profound attention due to their low formation damage and enhanc... Smart low-solid drilling fluids(SLSDFs)with thermo-controllable rheological properties and attractive thickening characteristics have recently captivated profound attention due to their low formation damage and enhanced cuttings lifting capacity.However,their applications to deep hole drilling at high temperatures have remained limited because of the thermal instability and environmental constraints of the thermo-associating polymers as additives.This work explored the synergistic benefits of thermo-associating polymer and biogenic nano-silica(B-SiNP)extracted from rice husk to improve the thermo-stability of SLSDF.This study shows that the nano-hybrid,TAP-S based on vinyl-terminated B-SiNP could potentially mitigate the limiting performance of conventional LSDF(F-2)caused by the failure of thermo-associating copolymers under elevated temperatures.TAP-S bearing drilling fluid(F-3)could preserve more than 5.6-fold of its initial properties(ca.apparent viscosity,plastic viscosity,yield point,and gel strength)with a nearly flat-gel profile in the temperature range of 25-230℃,which was higher than those of the counterpart F-2 and base fluid according to the results of rheological tests analysis.In addition,TAP-S exhibited an abrupt thermo-thickening characteristic with a magnitude declining by only 1.05-fold and the activation Gibbs free energy of 1339 kJ/mol above the plateau(ca.130℃),reflecting its less sensitivity compared to F-2 under a continuous heating process.As a result,a lower temperature was required to drive the dehydration of the residual fraction of lower critical solution temperature(LCST)in nano-hybrid structures than TAP according to the results of DSC analysis.Thus,lower energy was expected to disintegrate the residual hydrogen bonds formed between the LCST chains and surrounding water molecules at elevated temperatures.Moreover,TAP-S formed a solid-micro-crosslinking structure network which exhibited a more stable hydrodynamic diameter as revealed by DLS analysis.Compared with TAP,TAP-S consisted of a larger composite B-SiNP-TAP integrated spatial network structure based on the results of environmental scanning electron microscope,which conferred a degree of thermal conductivity characteristic for improved temperature resistance.This contributed to the effective binding onto bentonite particles for protection and maintained a relatively stable bentonite particle dispersion according to the results of EPM and particle size distribution analyses.Consequently,TAP-S fortified drilling fluid demonstrates improved rheological and filtration performance under severe downhole conditions.Therefore,TAP-S,the thermo-associating copolymer integrated with B-SiNP could find potential application as an eco-friendly viscosifier in LSDFs for deep-well drilling operations. 展开更多
关键词 polymer nano-hybrid Thermo-associating copolymer Biogenic nanosilica Rheological properties High temperature Low-solid drilling fluids
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Comparative Study on the Properties of Inorganic Silicate and Organic Phenolic Prepolymer Modified Poplar Wood by Vacuum Cycle Pressurization 被引量:3
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作者 Pengfei Guan Ping Li +3 位作者 Yiqiang Wu Xingong Li Guangming Yuan Yingfeng Zuo 《Journal of Renewable Materials》 SCIE EI 2022年第9期2451-2463,共13页
To enhance mechanical properties and improve flame retardancy and smoke suppression of fast-growing poplar wood in wood applications,the wood was impregnated and modified.An organic phenolic prepolymer and inorganic s... To enhance mechanical properties and improve flame retardancy and smoke suppression of fast-growing poplar wood in wood applications,the wood was impregnated and modified.An organic phenolic prepolymer and inorganic sodium silicate was used as contrasting impregnation modifiers and wood samples were impregnated by a bionic“respiration”method with alternating positive and negative pressure.The weight percentage gain,density increase ratio,mechanical properties(bending and compressive strength and hardness),and water absorption rate of inorganic and organic-impregnated modified poplar wood(IIMPW and OIMPW,respectively)were compared and these properties in IIMPW were found to be higher than those of OIMPW with the exception of the water absorption rate which was lower than the OIMPW.This was attributed to the superior absorption of sodium silicate that also improved the impregnation,reinforcement,and dimensional stability in the IIMPW.The chemical structure,crystalline structure,internal morphology,flame retardancy,smoke suppression,and thermal stability of IIMPW and OIMPW were characterized by FT-IR,XRD,SEM,CONE,and TGA.FT-IR and XRD results showed that,although IIMPW cellulose crystallinity reduced the most,more chemical bonds were come into being in IIMPW,which explained the better physical and mechanical properties of IIMPW.Compared with OIMPW,IIMPW had better flame retardant and smoke suppression performance. 展开更多
关键词 Poplar wood sodium silicate impregnation modification mechanical properties dimensional stability flame retardancy and smoke suppression
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STUDY ON THE POLYMERIZATION DEGREE OF SILICATE ANIONS IN THE SILICATE GLASS BY TRIMETHYLSILYLATION METHOD
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作者 朱翠兰 林云飞 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 1989年第1期37-46,共10页
In the present paper,a mixed solvent method is applied to the trimethylsilylation of silicate glass,and the polymerization degree and its distribution of silicate anions in the silicate glass are measured by means of ... In the present paper,a mixed solvent method is applied to the trimethylsilylation of silicate glass,and the polymerization degree and its distribution of silicate anions in the silicate glass are measured by means of the analyses of gas chromatography-mass spectrography. 展开更多
关键词 silicate anions silicate glass polymerIZATION Trimethylailylation
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THE STRUCTURE AND ELECTRICAL PROPERTIES IN POLYMER-LAYERED SILICATE NANOCOMPOSITES
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作者 陈文 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 1999年第3期16-22,共7页
The polymer-layered silicate nanocom- posites (PLSN) are preparedby the polymer melt interca- lation in layered silicate. By theanalyses of XRD, DSC, IR, NMR and Ac in pedance measurements etc, theex- Perimental resul... The polymer-layered silicate nanocom- posites (PLSN) are preparedby the polymer melt interca- lation in layered silicate. By theanalyses of XRD, DSC, IR, NMR and Ac in pedance measurements etc, theex- Perimental results show that polymer (PEO) can intercalate Intothe silicate interlayer in melt state, which leads to the Addition ofthe repeated distance of silicate. 展开更多
关键词 polymer-layered silicate nanocom posite MODIFICATION STRUCTURE
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Influence of Na_(2)SiO_(3)/NaOH Ratio on Calcined Magnesium Silicate Based Geopolymer——Experimental and Predictive Study
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作者 Premkumar R Ramesh Babu Chokkalingam +1 位作者 Meyyappan PL Shanmugasundaram M 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2023年第5期1077-1085,共9页
This study aims to investigate the behavior of alkali activated mortar,which is made of naturally available magnesium silicate as source material.For magnesium silicate,ultrafine natural steatite powder(UFNSP)is used ... This study aims to investigate the behavior of alkali activated mortar,which is made of naturally available magnesium silicate as source material.For magnesium silicate,ultrafine natural steatite powder(UFNSP)is used as the primary source of binder,and the activation is initiated through the alkali liquid which is proportioned in various combinations of silicate to hydroxide ratio(Na_(2)SiO_(3)/Na OH)ratio,and this ratio in this study varies from 1 to 3.The UFNSP is calcined at two difierent temperatures,700 and 1000℃.The mortar mix is proportioned as 1:3 between powder and the fine aggregate,and the mortar is prepared with hydroxide molarity(M)of 10 M.The mortar is cured for 48 hours at 60℃and the compressive strength was studied.All the mix were studied for its microstructural behavior along with compressive strength.The mix proportion of the mortar,and the results obtained through microstructural characterization were combinedly formed as input for artificial neural network(ANN)predictive modelling.The model is designed to predict the compressive strength,which is trained through Bayesian regularization algorithm with varying hidden neurons of 7 to 10.This experimental and predictive study shows that the strength is influenced by both Na_(2)SiO_(3)/Na OH ratio and calcination process.And the ANN is influenced by mainly calcination temperature and uncorrelation occurs in selected samples of 1000℃calcined UFNSP mix. 展开更多
关键词 magnesium silicate silicate alkali activation GEOpolymer UFNSP prediction
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Structure characterization for the geopolymer of sodium silicate and metakaolin
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作者 曹德光 《Journal of Chongqing University》 CAS 2005年第2期70-73,共4页
Geopolymers of metakaolin and sodium silicate were synthesized respectively with the ratios of the amount of SiO2 in the sodium silica solution to that of Al2O3 in metakaolinite equal to 1.0, and 0.66. The geopolymeri... Geopolymers of metakaolin and sodium silicate were synthesized respectively with the ratios of the amount of SiO2 in the sodium silica solution to that of Al2O3 in metakaolinite equal to 1.0, and 0.66. The geopolymeric structures of the products were investigated by 27Al and 29Si solid-state nuclear magnetic resonances with magic-angle spinning (MAS NMR), Fourier transform infrared spectroscopy (FTIR), X-ray powder diffraction (XRD), differential scanning colorimetry (DSC) and scanning electron microscopy (SEM). The reaction of the Al-O sheet in meakaolinite with low-order polymerized Si-O tetrahedral units such as monomer of SiO4 yields three-dimensional structures with the Q3 Si-O tetrahedral structure and the coordination of Al(IV) in the Al-O tetrahedral structure. The geopolymers are essentially X-ray amorphous. The assays by 27Al and 29Si NMR, FTIR confirm that the active structure in the metakaolinite is the sheet of Al-O with three coordination states. 展开更多
关键词 GEOpolymer MICROSTRUCTURE METAKAOLIN sodium silicate solution
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Polymer-infiltrated layered silicates for dental restorative materials 被引量:2
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作者 Ben-Cang Cui Jing Li +4 位作者 Yuan-Hua Lin Yang Shen Ming Li Xu-Liang Deng Ce-Wen Nan 《Rare Metals》 SCIE EI CAS CSCD 2019年第11期1003-1014,共12页
Layered porous ceramic used for polymer-infiltrated-ceramic-network materials(PICNs) may be a promising candidate for dental restoration.The effect of sintering temperature of ceramic green bodies on mechanical and op... Layered porous ceramic used for polymer-infiltrated-ceramic-network materials(PICNs) may be a promising candidate for dental restoration.The effect of sintering temperature of ceramic green bodies on mechanical and optical properties of PICNs is unclear.The purpose was to fabricate PICNs and evaluate their mechanical and optical properties.Polymer-infiltrated layered silicates for dental restorative materials were prepared via infiltrating polymerizable monomers into partially sintered porous silicates and thermo-curing.Bending samples for flexural strength and fracture toughness were fabricated(sample numbers of n=15).Vickers hardness and elastic modulus were measured via nano-indentation(n=10).One-way ANOVA and Weibull statistics were used for statistical analysis.Optical property was characterized by spectral reflectance.Brittleness index was used to characterize the machinability of the materials.Microstructures and phase structures were investigated using scanning electron microscopy(SEM) and X-ray diffractometer(XRD),respectively.Flexural strength of polymer-infiltrated layered silicates varied from 91.29 to 155.19 MPa,fracture toughness ranged from 1.186 to 1.782 MPa·m^1/2,Vickers hardness ranged from 1.165 to 9.596 GPa,and elastic modulus ranged from 25.35 to 100.50 GPa.The formed glass phases at 1200 and 1300℃ showed influences on corresponding optical property,which could be observed from spectral reflectance.A kind of PICNs was fabricated by infiltrating polymerizable monomers into layered porous ceramic networks.Sintering temperature could have dramatic effects on the mechanical and optical properties of porous ceramics and PICNs.These kinds of materials possess similar properties to that of natural tooth and could be used for dental restoration. 展开更多
关键词 CAD/CAM BLOCKS DENTAL composites Mechanical properties polymer-infiltrated-ceramic-networks
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Concrete Based on Fly Ash Alumosilicate Polymers
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作者 R. Sulc T. Strnad +4 位作者 F. Skvara P. Svoboda Z. Bittnar V. Smilauer L. Kopecky 《Journal of Environmental Science and Engineering》 2011年第6期728-735,共8页
Concretes on the basis of the alumosilicate polymer can be prepared by alkali activation (NaOH, sodium water glass) of waste brown coal fly ash. The preparation is possible: (1) by using a short-term heating of t... Concretes on the basis of the alumosilicate polymer can be prepared by alkali activation (NaOH, sodium water glass) of waste brown coal fly ash. The preparation is possible: (1) by using a short-term heating of the concrete mix (to 80 ℃); or (2) by allowing the mix to harden spontaneously at a temperature of 20 ℃. The concretes prepared by short-time heating attain high strength values after their preparation; the values are comparable to those characterizing concretes obtained on the basis of Portland cement. The strength development of concretes hardening at 20 ℃ is substantially less steep but, nevertheless, the strength attained after about 60 days is practically identical with that of the concretes exposed to a short-time heating. The shrinkage of concretes prepared by short-time heating is very small as compared with the concretes allowed to harden spontaneously; the shrinkage of latter concretes is larger than that of the concretes on the basis of Portland cement. The concretes on the basis of alumosilicate polymer exhibit much better resistance to the corrosive action of the environment as compared with those prepared on the basis of Portland cement. 展开更多
关键词 Alumosilicate polymer GEOpolymer CONCRETE fly ash
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Study on Properties and Synthesize of a new Polymeric Aluminum Sulfate-silicate
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作者 Yu Shu-rong Wang Qing-ning Zhang Fei-long Ye Qi-zhi 《合成化学》 CAS CSCD 2004年第z1期137-137,共1页
关键词 polymerIC basic ALUMINUM silicate-sulfate flocculants SEWERAGE treatment
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A cadmium(Ⅱ)coordination polymer based on a semirigid tetracarboxylate ligand for highly selective detection of Fe^(3+)and 4-nitrophenol 被引量:1
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作者 BAI Yu WANG Jijiang +4 位作者 TANG Long YUE Erlin BAI Chao WANG Xiao ZHANG Yuqi 《无机化学学报》 北大核心 2025年第6期1217-1226,共10页
A novel coordination polymer(CP){[Cd_(2)(L)(1,4-bimb)_(1.5)(DMF)_(2)]·DMF}n(1)(H_(4)L=5,5'-[1,1'-biphenyl-4,4'-diylbis(oxy)]diisophthalic acid,1,4-bimb=1,4-bis(imidazole-1-ylmethyl)-benzene)has been d... A novel coordination polymer(CP){[Cd_(2)(L)(1,4-bimb)_(1.5)(DMF)_(2)]·DMF}n(1)(H_(4)L=5,5'-[1,1'-biphenyl-4,4'-diylbis(oxy)]diisophthalic acid,1,4-bimb=1,4-bis(imidazole-1-ylmethyl)-benzene)has been designed and synthesized through solvothermal reaction.Structural analysis shows that Cd(Ⅱ)is connected by H4L and 1,4-bimb to form a 2D network,and 1,4-bimb further expands the 2D network into a 3D framework.CP 1 can be used as an excellent fluorescence sensor for Fe^(3+)and 4-nitrophenol(4-NP),with low detection limits and good anti-interference.The detection limits of Fe^(3+)and 4-NP were 0.034 and 0.031μmol·L^(-1),respectively.In addition,the fluorescence quenching mechanism was studied.1 was successfully applied to determine Fe^(3+)and 4-NP content in the Yanhe River water sample.CCDC:2351092. 展开更多
关键词 coordination polymer Fe^(3+) 4-NITROPHENOL fluorescence sensing
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An Ion-imprinted Silica Gel Polymer Prepared by Surface Imprinting Technique Combined with Aqueous Solution Polymerization for Selective Adsorption of Ni(Ⅱ) from Aqueous Solution 被引量:7
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作者 Hong-Xing He Qiang Gan Chang-Gen Feng 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2018年第4期462-471,共10页
A novel Ni(Ⅱ) ion-imprinted silica gel polymer was prepared via the surface imprinting technique combined with aqueous solution polymerization by using 2-acrylamido-2-methyl-1-propanesulfonic acid(AMPS) as a func... A novel Ni(Ⅱ) ion-imprinted silica gel polymer was prepared via the surface imprinting technique combined with aqueous solution polymerization by using 2-acrylamido-2-methyl-1-propanesulfonic acid(AMPS) as a functional monomer for the selective separation of Ni(Ⅱ) from aqueous solution. The sorbent showed good chemical and thermal stability. Kinetics studies indicated that the equilibrium adsorption was achieved within 10 min and the adsorption kinetics fitted well with the pseudo-second-order kinetic model. The maximum adsorption capacity of the ion-imprinted polymer towards Ni(Ⅱ) at the optimal p H of 7.0 was 66.22 mg·g^(-1). The relative selectivity coefficients of the sorbent were 9.23, 15.71, 14.72 and 20.15 for Ni(Ⅱ)/Co(Ⅱ), Ni(Ⅱ)/Cu(Ⅱ), Ni(Ⅱ)/Zn(Ⅱ) and Ni(Ⅱ)/Pb(Ⅱ), respectively. The adsorption isotherm fitted well with Langmuir isotherm model. The thermodynamic results indicated that the adsorption of Ni(Ⅱ) was a spontaneous and endothermic process. The sorbent showed good reusability evidenced by six cycles of adsorption/desorption experiments. The precision of this method is satisfactory. Thus, the prepared sorbent can be considered as a promising sorbent for selective separation of Ni(Ⅱ) in real water samples. 展开更多
关键词 Ion-imprinted polymer Ni(II) ion Surface imprinting technology Selective adsorption Aqueous solution polymerization
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