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Magnetic Resonance Letters 2024年第3期4卷 35-41页

作者： Zhiwei Yan Yue-Qi Ye Rongchun Zhang South China Advanced Institute for Soft Matter Science and Technology(AISMST) School of Emergent Soft Matter(SESM)South China University of TechnologyGuangzhou510640China JEOL(Beijing)Co. Ltd.Haidian DistrictBeijing100190China JEOL Ltd. MusashinoAkishimaTokyo196-8558Japan Guangdong Provincial Key Laboratory of Functional and Intelligent Hybrid Materials and Devices South China University of TechnologyGuangzhou510640China

INADEQUATE(Incredible Natural Abundance DoublE QUAntum Transfer Experiment)is one of the most important techniques in revealing the carbon skeleton of organic solids in solid-state NMR ***,its use for structural analysis is quite limited due to the low natural abundance of^(13)C-^(13)C connectivity(~0.01%)and thus low ***,in semi-solids like rubbers,the sensitivity will be further significantly reduced by the inefficient cross polarization from 1H to^(13)C due to molecular motions induced averaging of^(1)H-^(13)C dipolar ***,in this study,we demonstrate that transient nuclear Overhauser effect(NOE)can be used to efficiently enhance^(13)C signals,and thus enable rapid acquisition of two-dimensional(2D)^(13)C INADEQUATE spectra of *** chlorobutyl rubber as the model system,it is found that an overall signalto-noise ratio(SNR)enhancement about 22%can be achieved,leading to significant timesaving by about 33%as compared to the direct polarization-based INADEQUATE *** experimental results on natural rubber and ethylene propylene diene monomer(EPDM)rubber are also shown to demonstrate the robust performance of transient NOE enhanced INADEQUATE experiment.

关键词： Transient NOE INADEQUATE Carbon skeleton rubbers

Deuterium NMR Studies on the Orientational Order Generated in Strained rubbers

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Chemical Research in Chinese Universities 1992年第2期8卷 110-113页

作者： LI Fei, YANG Dai-wen, GAO Ping and QIU Zu-wen (Institute of Theoretical Chemistry, Jilin University, Changchun, 130023)

The present paper deals with the induced orientational order of the probe molecules dissolved in the uniaxially strained rubbers measured by using deuterium NMR. The distinctive dependence of the quadrupolar splitting on the swelling, elongation and crosslinking density was observed. The orientational order arising from the correlation between chain segments decreases with the increase of the numbers of both links between junctions and solvent molecules around segments.

关键词： Orientational order rubbers Deuterium NMR Crosslinking density,Segment-segment correlation

Solid-state NMR of vulcanized natural rubber/butadiene rubber blends:Local organization and cross-linking heterogeneities This article is part of the virtual special issue“Solid-state NMR studies on polymers and biological solids”

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Magnetic Resonance Letters 2024年第4期4卷 49-61页

作者： Pierre Daniel Cristina Coelho-Diogo Valérie Gaucher Grégory Stoclet Clément Robin Cédric Lorthioir Sorbonne Université CNRSLaboratoire de Chimie de la Matière Condensée de ParisLCMCPUMR 757475005 ParisFrance Sorbonne Université CNRSFédération Chimie et Matériaux de Paris-CentreFR 248275005 ParisFrance Univ.Lille CNRSINRAECentrale LilleUnitéMatériaux et TransformationsUMETUMR 820759000 LilleFrance Hutchinson Research and Innovation Center 45120 Châlette-sur-LoingFrance

Elastomer blends,among which natural rubber(NR)and butadiene rubber(BR),are involved in many components of the automotive/tire industry.A comprehensive understanding of their mechanical behavior requires,among other features,a detailed description of the crosslink density in these *** the case of vulcanized immiscible blends,the distribution of the cross-link density within each of the NR-and BR-rich domains is key information,but difficult to determine using the conventional approaches used for one-component crosslinked *** this study,the vulcanization within NR/BR blends is investigated using a robust^(1)H double-quantum(DQ)MAS recoupling experiment,*** kinds of cross-linked NR/BR blends were considered with two different microstructures for the BR *** bulk organization of the resulting blends was first probed by analyzing the^(1)H spin-lattice relaxation *** a second step,BaBa-xy16 was used to investigate,in a selective way,the cross-link heterogeneities within NR/BR *** particular,for immiscible NR/BR mixtures,the distribution of the cross-link density between both phases was compared and the observed differences were discussed.

关键词： rubbers Blends Cross-linking 1H solid-state NMR Relaxation Double-quantum NMR Dipolar recoupling

Modified rubberized stone matrix asphalt for Nineveh roads

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Journal of Harbin Institute of Technology(New Series) 2008年第3期15卷 356-360页

作者： Al-Hadidy AI 谭忆秋 School of Transportation Science and Engineering Harbin Institute of Technology

To evaluate the effects of Crumb Rubber Modifiers (CRMS) on basic engineering properties (i.e. Marshall, tensile strength, and compressive strength) of stone matrix asphalt mixtures, the ASTM testing and procedures were employed. Results of the evaluation were used to quantify the effect of CRM source and CRM content on engineering properties at testing temperatures of 25 ℃ and 60 ℃. Statistical models were developed, which represent the nature of effects on performance-related properties of stone matrix asphalt mixtures.

关键词： rubbers asphalt mixtures stone matrix asphalt tests

The Relative Viscosity of Concentrated Rubber Suspensions and Viscoelastic Modulus of 3D Сross-Linked Elastomers Filled with Solid Particles

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Open Journal of Applied Sciences 2013年第8期3卷 477-481页

作者： Alexandr Ermilov Ergasch Nurullaev Perm National Research Polytechnic University Perm Russia

For the first time, this paper describes the concentration dependence of the relative dynamic viscosity coefficient of rubber suspensions and the initial viscoelastic modulus of 3D cross-linked elastomers on the maximum volume filling with solid polydisperse particles. It allows to predict the rheological and mechanical properties of the polymer compositions being developed now. In this paper, we present the first experimental study of the pole of the concurrent lines of the concentration dependence in the coordinates of the linear form. The pole validates the invariant value of the constant of the developed equation and allows the experimental determination of the maximum volume filling of polymer binders filled with separate fractions or polydisperse mixtures. The results of the study are recommended for use in developing new polymer composite materials.

关键词： Viscosity Mechanical Destruction Elastomeric Composites with Dispersed Fillers Rheology rubbers Polymeric Binders Asphalt Coatings