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Parameter Visualization of Benchtop Nuclear Magnetic Resonance Spectra toward Food Process Monitoring. Processes (Basel) 2022. [DOI: 10.3390/pr10071264] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/07/2022] Open
Abstract
Low-cost and user-friendly benchtop low-field nuclear magnetic resonance (NMR) spectrometers are typically used to monitor food processes in the food industry. Because of excessive spectral overlap, it is difficult to characterize food mixtures using low-field NMR spectroscopy. In addition, for standard compounds, low-field benchtop NMR data are typically unavailable compared to high-field NMR data, which have been accumulated and are reusable in public databases. This work focused on NMR parameter visualization of the chemical structure and mobility of mixtures and the use of high-field NMR data to analyze benchtop NMR data to characterize food process samples. We developed a tool to easily process benchtop NMR data and obtain chemical shifts and T2 relaxation times of peaks, as well as transform high-field NMR data into low-field NMR data. Line broadening and time–frequency analysis methods were adopted for data processing. This tool can visualize NMR parameters to characterize changes in the components and mobilities of food process samples using benchtop NMR data. In addition, assignment errors were smaller when the spectra of standard compounds were identified by transferring the high-field NMR data to low-field NMR data rather than directly using experimentally obtained low-field NMR spectra.
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Materials informatics approach using domain modelling for exploring structure-property relationships of polymers. Sci Rep 2022; 12:10558. [PMID: 35732681 PMCID: PMC9217937 DOI: 10.1038/s41598-022-14394-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Accepted: 06/06/2022] [Indexed: 11/23/2022] Open
Abstract
In the development of polymer materials, it is an important issue to explore the complex relationships between domain structure and physical properties. In the domain structure analysis of polymer materials, 1H-static solid-state NMR (ssNMR) spectra can provide information on mobile, rigid, and intermediate domains. But estimation of domain structure from its analysis is difficult due to the wide overlap of spectra from multiple domains. Therefore, we have developed a materials informatics approach that combines the domain modeling (http://dmar.riken.jp/matrigica/) and the integrated analysis of meta-information (the elements, functional groups, additives, and physical properties) in polymer materials. Firstly, the 1H-static ssNMR data of 120 polymer materials were subjected to a short-time Fourier transform to obtain frequency, intensity, and T2 relaxation time for domains with different mobility. The average T2 relaxation time of each domain is 0.96 ms for Mobile, 0.55 ms for Intermediate (Mobile), 0.32 ms for Intermediate (Rigid), and 0.11 ms for Rigid. Secondly, the estimated domain proportions were integrated with meta-information such as elements, functional group and thermophysical properties and was analyzed using a self-organization map and market basket analysis. This proposed method can contribute to explore structure–property relationships of polymer materials with multiple domains.
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Influence of Sulfur-Curing Conditions on the Dynamics and Crosslinking of Rubber Networks: A Time-Domain NMR Study. Polymers (Basel) 2022; 14:polym14040767. [PMID: 35215681 PMCID: PMC8880187 DOI: 10.3390/polym14040767] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Revised: 02/13/2022] [Accepted: 02/14/2022] [Indexed: 11/25/2022] Open
Abstract
The characterization of the structural and dynamic properties of rubber networks is of fundamental importance in rubber science and technology to design materials with optimized mechanical properties. In this work, natural and isoprene rubber networks obtained by curing at three different temperatures (140, 150, and 170 °C) and three different sulfur contents (1, 2, and 3 phr) in the presence of a 3 phr accelerator were studied using a combination of low-field time-domain NMR (TD-NMR) techniques, including 1H multiple-quantum experiments for the measurement of residual dipolar couplings (Dres), the application of the Carr–Purcell–Meiboom–Gill pulse sequence for the measurement of the transverse magnetization decay and the extraction of 1H T2 relaxation times, and the use of field cycling NMR relaxometry for the determination of T1 relaxation times. The microscopic properties determined by TD-NMR experiments were discussed in comparison with the macroscopic properties obtained using equilibrium swelling, moving die rheometer, and calorimetric techniques. The obtained correlations between NMR observables, crosslink density values, maximum torque values, and glass transition temperatures provided insights into the effects of the vulcanization temperature and accelerator/sulfur ratio on the structure of the polymer networks, as well as on the effects of crosslinking on the segmental dynamics of elastomers. Dres and T2 were found to show linear correlations with the crosslink density determined by equilibrium swelling, while T1 depends on the local dynamics of polymer segments related to the glass transition, which is also affected by chemical modifications of the polymer chains occurring during vulcanization.
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Calucci L, Pizzanelli S, Mandoli A, Birczyński A, Lalowicz ZT, De Monte C, Ricci L, Bronco S. Unravelling Main- and Side-Chain Motions in Polymers with NMR Spectroscopy and Relaxometry: The Case of Polyvinyl Butyral. Polymers (Basel) 2021; 13:2686. [PMID: 34451226 PMCID: PMC8398131 DOI: 10.3390/polym13162686] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Revised: 07/30/2021] [Accepted: 08/06/2021] [Indexed: 11/19/2022] Open
Abstract
Polyvinyl butyral (PVB) is an amorphous polymer employed in many technological applications. In order to highlight the relationships between macroscopic properties and dynamics at a microscopic level, motions of the main-chain and of the propyl side-chains were investigated between Tg - 288 °C and Tg + 55 °C, with Tg indicating the glass transition temperature. To this aim, a combination of solid state Nuclear Magnetic Resonance (NMR) methods was applied to two purposely synthesized PVB isotopomers: one fully protonated and the other perdeuterated on the side-chains. 1H time domain NMR and 1H field cycling NMR relaxometry experiments, performed across and above Tg, revealed that the dynamics of the main-chain corresponds to the α-relaxation associated to the glass transition, which was previously characterized by dielectric spectroscopy. A faster secondary relaxation was observed for the first time and ascribed to side-chains. The geometry and rate of motions of the different groups in the side-chains were characterized below Tg by 2H NMR spectroscopy.
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Affiliation(s)
- Lucia Calucci
- Istituto di Chimica dei Composti OrganoMetallici, Consiglio Nazionale delle Ricerche—CNR, Via G. Moruzzi 1, 56124 Pisa, Italy;
- Centro per l’Integrazione della Strumentazione Scientifica dell’Università di Pisa (CISUP), Lungarno Pacinotti 43/44, 56126 Pisa, Italy
| | - Silvia Pizzanelli
- Istituto di Chimica dei Composti OrganoMetallici, Consiglio Nazionale delle Ricerche—CNR, Via G. Moruzzi 1, 56124 Pisa, Italy;
- Centro per l’Integrazione della Strumentazione Scientifica dell’Università di Pisa (CISUP), Lungarno Pacinotti 43/44, 56126 Pisa, Italy
| | - Alessandro Mandoli
- Dipartimento di Chimica e Chimica Industriale, Università di Pisa, Via G. Moruzzi 13, 56124 Pisa, Italy;
| | - Artur Birczyński
- Institute of Technology, The Pedagogical University of Kraków, Podchorążych 2, 30-084 Krakow, Poland;
| | - Zdzisław T. Lalowicz
- Institute of Nuclear Physics, Polish Academy of Sciences, ul. Radzikowskiego 152, 31-342 Krakow, Poland;
| | - Cristina De Monte
- Istituto per i Processi Chimico-Fisici, Consiglio Nazionale delle Ricerche—CNR, Via G. Moruzzi 1, 56124 Pisa, Italy; (C.D.M.); (L.R.); (S.B.)
| | - Lucia Ricci
- Istituto per i Processi Chimico-Fisici, Consiglio Nazionale delle Ricerche—CNR, Via G. Moruzzi 1, 56124 Pisa, Italy; (C.D.M.); (L.R.); (S.B.)
| | - Simona Bronco
- Istituto per i Processi Chimico-Fisici, Consiglio Nazionale delle Ricerche—CNR, Via G. Moruzzi 1, 56124 Pisa, Italy; (C.D.M.); (L.R.); (S.B.)
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5
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Nardelli F, Martini F, Lee J, Lluvears-Tenorio A, La Nasa J, Duce C, Ormsby B, Geppi M, Bonaduce I. The stability of paintings and the molecular structure of the oil paint polymeric network. Sci Rep 2021; 11:14202. [PMID: 34244532 PMCID: PMC8270892 DOI: 10.1038/s41598-021-93268-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Accepted: 06/11/2021] [Indexed: 02/06/2023] Open
Abstract
A molecular-level understanding of the structure of the polymeric network formed upon the curing of air-drying artists' oil paints still represents a challenge. In this study we used a set of analytical methodologies classically employed for the characterisation of a paint film-based on infrared spectroscopy and mass spectrometry-in combination with solid state NMR (SSNMR), to characterise model paint layers which present different behaviours towards surface cleaning with water, a commonly applied procedure in art conservation. The study demonstrates, with the fundamental contribution of SSNMR, a relationship between the painting stability and the chemical structure of the polymeric network. In particular, it is demonstrated for the first time that a low degree of cross-linking in combination with a high degree of oxidation of the polymeric network render the oil paint layer sensitive to water.
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Affiliation(s)
- Francesca Nardelli
- Department of Chemistry and Industrial Chemistry, University of Pisa, Via Giuseppe Moruzzi 13, 56124, Pisa, Italy
| | - Francesca Martini
- Department of Chemistry and Industrial Chemistry, University of Pisa, Via Giuseppe Moruzzi 13, 56124, Pisa, Italy
- Centro Per L'Integrazione Della Strumentazione Scientifica Dell'Università Di Pisa (CISUP), Lungarno Pacinotti 43, 56126, Pisa, Italy
| | - Judith Lee
- Conservation Department, Tate, Millbank, London, SW1P 4RG, UK
| | - Anna Lluvears-Tenorio
- Department of Chemistry and Industrial Chemistry, University of Pisa, Via Giuseppe Moruzzi 13, 56124, Pisa, Italy
| | - Jacopo La Nasa
- Department of Chemistry and Industrial Chemistry, University of Pisa, Via Giuseppe Moruzzi 13, 56124, Pisa, Italy
| | - Celia Duce
- Department of Chemistry and Industrial Chemistry, University of Pisa, Via Giuseppe Moruzzi 13, 56124, Pisa, Italy
| | - Bronwyn Ormsby
- Conservation Department, Tate, Millbank, London, SW1P 4RG, UK
| | - Marco Geppi
- Department of Chemistry and Industrial Chemistry, University of Pisa, Via Giuseppe Moruzzi 13, 56124, Pisa, Italy
- Centro Per L'Integrazione Della Strumentazione Scientifica Dell'Università Di Pisa (CISUP), Lungarno Pacinotti 43, 56126, Pisa, Italy
| | - Ilaria Bonaduce
- Department of Chemistry and Industrial Chemistry, University of Pisa, Via Giuseppe Moruzzi 13, 56124, Pisa, Italy.
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6
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Nardelli F, Martini F, Carignani E, Rossi E, Borsacchi S, Cettolin M, Susanna A, Arimondi M, Giannini L, Geppi M, Calucci L. Glassy and Polymer Dynamics of Elastomers by 1H-Field-Cycling NMR Relaxometry: Effects of Fillers. J Phys Chem B 2021; 125:4546-4554. [PMID: 33885314 PMCID: PMC8279540 DOI: 10.1021/acs.jpcb.1c00885] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Revised: 04/07/2021] [Indexed: 11/30/2022]
Abstract
1H spin-lattice relaxation rate (R1) dispersions were acquired by field-cycling (FC) NMR relaxometry between 0.01 and 35 MHz over a wide temperature range on polyisoprene rubber (IR), either unfilled or filled with different amounts of carbon black, silica, or a combination of both, and sulfur cured. By exploiting the frequency-temperature superposition principle and constructing master curves for the total FC NMR susceptibility, χ″(ω) = ωR1(ω), the correlation times for glassy dynamics, τs, were determined. Moreover, the contribution of polymer dynamics, χpol″(ω), to χ″(ω) was singled out by subtracting the contribution of glassy dynamics, χglass″(ω), well represented by the Cole-Davidson spectral density. Glassy dynamics resulted moderately modified by the presence of fillers, τs values determined for the filled rubbers being slightly different from those of the unfilled one. Polymer dynamics was affected by the presence of fillers in the Rouse regime. A change in the frequency dependence of χpol″(ω) at low frequencies was observed for all filled rubbers, more pronounced for those reinforced with silica, which suggests that the presence of the filler particles can affect chain conformations, resulting in a different Rouse mode distribution, and/or interchain interactions modulated by translational motions.
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Affiliation(s)
- Francesca Nardelli
- Dipartimento
di Chimica e Chimica Industriale, Università
di Pisa, via G. Moruzzi 13, 56124 Pisa, Italy
- Istituto
di Chimica dei Composti OrganoMetallici, Consiglio Nazionale delle
Ricerche, via G. Moruzzi
1, 56124 Pisa, Italy
| | - Francesca Martini
- Dipartimento
di Chimica e Chimica Industriale, Università
di Pisa, via G. Moruzzi 13, 56124 Pisa, Italy
- Istituto
di Chimica dei Composti OrganoMetallici, Consiglio Nazionale delle
Ricerche, via G. Moruzzi
1, 56124 Pisa, Italy
- Centro
per l’Integrazione della Strumentazione Scientifica dell’Università
di Pisa (CISUP), Lungarno
Pacinotti 43, 56126 Pisa, Italy
| | - Elisa Carignani
- Dipartimento
di Chimica e Chimica Industriale, Università
di Pisa, via G. Moruzzi 13, 56124 Pisa, Italy
- Istituto
di Chimica dei Composti OrganoMetallici, Consiglio Nazionale delle
Ricerche, via G. Moruzzi
1, 56124 Pisa, Italy
| | - Elena Rossi
- Dipartimento
di Chimica e Chimica Industriale, Università
di Pisa, via G. Moruzzi 13, 56124 Pisa, Italy
| | - Silvia Borsacchi
- Istituto
di Chimica dei Composti OrganoMetallici, Consiglio Nazionale delle
Ricerche, via G. Moruzzi
1, 56124 Pisa, Italy
- Centro
per l’Integrazione della Strumentazione Scientifica dell’Università
di Pisa (CISUP), Lungarno
Pacinotti 43, 56126 Pisa, Italy
| | | | | | | | - Luca Giannini
- Pirelli
Tyre SpA, Viale Sarca 222, 20126 Milano, Italy
| | - Marco Geppi
- Dipartimento
di Chimica e Chimica Industriale, Università
di Pisa, via G. Moruzzi 13, 56124 Pisa, Italy
- Istituto
di Chimica dei Composti OrganoMetallici, Consiglio Nazionale delle
Ricerche, via G. Moruzzi
1, 56124 Pisa, Italy
- Centro
per l’Integrazione della Strumentazione Scientifica dell’Università
di Pisa (CISUP), Lungarno
Pacinotti 43, 56126 Pisa, Italy
| | - Lucia Calucci
- Istituto
di Chimica dei Composti OrganoMetallici, Consiglio Nazionale delle
Ricerche, via G. Moruzzi
1, 56124 Pisa, Italy
- Centro
per l’Integrazione della Strumentazione Scientifica dell’Università
di Pisa (CISUP), Lungarno
Pacinotti 43, 56126 Pisa, Italy
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7
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Time Domain NMR in Polymer Science: From the Laboratory to the Industry. APPLIED SCIENCES-BASEL 2019. [DOI: 10.3390/app9091801] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Highly controlled polymers and nanostructures are increasingly translated from the lab to the industry. Together with the industrialization of complex systems from renewable sources, a paradigm change in the processing of plastics and rubbers is underway, requiring a new generation of analytical tools. Here, we present the recent developments in time domain NMR (TD-NMR), starting with an introduction of the methods. Several examples illustrate the new take on traditional issues like the measurement of crosslink density in vulcanized rubber or the monitoring of crystallization kinetics, as well as the unique information that can be extracted from multiphase, nanophase and composite materials. Generally, TD-NMR is capable of determining structural parameters that are in agreement with other techniques and with the final macroscopic properties of industrial interest, as well as reveal details on the local homogeneity that are difficult to obtain otherwise. Considering its moderate technical and space requirements of performing, TD-NMR is a good candidate for assisting product and process development in several applications throughout the rubber, plastics, composites and adhesives industry.
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8
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Cobani E, Tagliaro I, Geppi M, Giannini L, Leclère P, Martini F, Nguyen TC, Lazzaroni R, Scotti R, Tadiello L, Di Credico B. Hybrid Interface in Sepiolite Rubber Nanocomposites: Role of Self-Assembled Nanostructure in Controlling Dissipative Phenomena. NANOMATERIALS (BASEL, SWITZERLAND) 2019; 9:E486. [PMID: 30934729 PMCID: PMC6523625 DOI: 10.3390/nano9040486] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Revised: 03/22/2019] [Accepted: 03/24/2019] [Indexed: 01/14/2023]
Abstract
Sepiolite (Sep)⁻styrene butadiene rubber (SBR) nanocomposites were prepared by using nano-sized sepiolite (NS-SepS9) fibers, obtained by applying a controlled surface acid treatment, also in the presence of a silane coupling agent (NS-SilSepS9). Sep/SBR nanocomposites were used as a model to study the influence of the modified sepiolite filler on the formation of immobilized rubber at the clay-rubber interface and the role of a self-assembled nanostructure in tuning the mechanical properties. A detailed investigation at the macro and nanoscale of such self-assembled structures was performed in terms of the organization and networking of Sep fibers in the rubber matrix, the nature of both the filler⁻filler and filler⁻rubber interactions, and the impact of these features on the reduced dissipative phenomena. An integrated multi-technique approach, based on dynamic measurements, nuclear magnetic resonance analysis, and morphological investigation, assessed that the macroscopic mechanical properties of clay nanocomposites can be remarkably enhanced by self-assembled filler structures, whose formation can be favored by manipulating the chemistry at the hybrid interfaces between the clay particles and the polymers.
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Affiliation(s)
- Elkid Cobani
- Department of Materials Science, INSTM, University of Milano-Bicocca, Via R. Cozzi, 55, 20125 Milano, Italy.
| | - Irene Tagliaro
- Department of Materials Science, INSTM, University of Milano-Bicocca, Via R. Cozzi, 55, 20125 Milano, Italy.
| | - Marco Geppi
- Dipartimento di Chimica e Chimica Industriale, University of Pisa, Via Moruzzi 13, 56124 Pisa, Italy.
| | | | - Philippe Leclère
- Service de Chimie des Matériaux Nouveaux, Centre d'Innovation et de Recherche en MAtériaux Polymères (CIRMAP), Université de Mons-UMONS, 7000 Mons, Belgium.
| | - Francesca Martini
- Dipartimento di Chimica e Chimica Industriale, University of Pisa, Via Moruzzi 13, 56124 Pisa, Italy.
| | - Thai Cuong Nguyen
- Service de Chimie des Matériaux Nouveaux, Centre d'Innovation et de Recherche en MAtériaux Polymères (CIRMAP), Université de Mons-UMONS, 7000 Mons, Belgium.
| | - Roberto Lazzaroni
- Service de Chimie des Matériaux Nouveaux, Centre d'Innovation et de Recherche en MAtériaux Polymères (CIRMAP), Université de Mons-UMONS, 7000 Mons, Belgium.
| | - Roberto Scotti
- Department of Materials Science, INSTM, University of Milano-Bicocca, Via R. Cozzi, 55, 20125 Milano, Italy.
| | | | - Barbara Di Credico
- Department of Materials Science, INSTM, University of Milano-Bicocca, Via R. Cozzi, 55, 20125 Milano, Italy.
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9
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Bokobza L. Natural Rubber Nanocomposites: A Review. NANOMATERIALS (BASEL, SWITZERLAND) 2018; 9:E12. [PMID: 30583554 PMCID: PMC6359587 DOI: 10.3390/nano9010012] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Revised: 12/16/2018] [Accepted: 12/18/2018] [Indexed: 11/16/2022]
Abstract
This paper reviews studies carried out on natural rubber filled with nanofillers such as spherical silica particles (generated by the sol gel reaction), clays and carbon nanostructures. It is shown that the mechanical response of NR is influenced by several parameters including the processing conditions, the state of filler dispersion, the polymer-filler interactions and the filler morphological aspects. Even if the sol gel process conducted in vulcanized rubber yields almost ideal dispersions, rod-shaped particles such as clay, carbon fibers or carbon nanotubes are by far more efficient in terms of mechanical reinforcement on account of their anisotropic character and their ability to orientate in the direction of stretch. The efficiency of layered fillers such as clays or graphitic structures clearly depends on the way they are dispersed (exfoliated) in the rubber. Complete exfoliation still remains difficult to achieve which limits the tremendous nanoreinforcement expected from a single layer of clay or graphite. In all cases, the onset of crystallization is observed at a lower strain value than that of the unfilled matrix due to strain amplification effects.
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