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Atiq O, Ricci E, Baschetti MG, De Angelis MG. Molecular Simulations of Hydrogen Sorption in Semicrystalline High-Density Polyethylene: The Impact of the Surface Fraction of Tie-Chains. J Phys Chem B 2024; 128:2799-2810. [PMID: 38452257 PMCID: PMC10961721 DOI: 10.1021/acs.jpcb.3c07705] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Revised: 02/16/2024] [Accepted: 02/19/2024] [Indexed: 03/09/2024]
Abstract
The modeling of the barrier properties of semicrystalline polymers has gained interest following the possible application of such materials as protective liners for the safe supply of pressurized hydrogen. The mass transport in such systems is intimately related to the complex intercalation between the crystal and amorphous phases, which was approached in this work through an all-atom representation of high-density polyethylene structures with a tailored fraction of amorphous-crystalline connections (tie-chains). Simulations of the polymer pressure-volume-temperature data and hydrogen sorption were performed by means of molecular dynamics and the Widom test particle insertion method. The discretization of the simulation domains of the semicrystalline structures allowed us to obtain profiles of density, degree of order, and gas solubility. The results indicated that the gas sorption in the crystalline regions is negligible and that the confinement of the amorphous phase between crystals induces a significant increase in density and a drop in the sorption capacity, even in the absence of tie-chains. Adding ties between the crystal and the amorphous phase results in further densification, an increase of the lamella tilt angle, and a decrease in the degree of crystallinity and hydrogen sorption coefficient, in agreement with several literature references.
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Affiliation(s)
- Omar Atiq
- Department
of Civil, Chemical, Environmental and Material Engineering, (DICAM), Alma Mater Studiorum − Università di
Bologna, via Terracini 28, Bologna 40131, Italy
- DPI, P.O. Box 902, Eindhoven 5600 AX, The Netherlands
| | - Eleonora Ricci
- Institute
for Materials and Processes, School of Engineering, University of Edinburgh, Sanderson Building, Robert Stevenson Road, Scotland EH9 3FB, U.K.
- DPI, P.O. Box 902, Eindhoven 5600 AX, The Netherlands
| | - Marco Giacinti Baschetti
- Department
of Civil, Chemical, Environmental and Material Engineering, (DICAM), Alma Mater Studiorum − Università di
Bologna, via Terracini 28, Bologna 40131, Italy
- DPI, P.O. Box 902, Eindhoven 5600 AX, The Netherlands
| | - Maria Grazia De Angelis
- Institute
for Materials and Processes, School of Engineering, University of Edinburgh, Sanderson Building, Robert Stevenson Road, Scotland EH9 3FB, U.K.
- Department
of Civil, Chemical, Environmental and Material Engineering, (DICAM), Alma Mater Studiorum − Università di
Bologna, via Terracini 28, Bologna 40131, Italy
- DPI, P.O. Box 902, Eindhoven 5600 AX, The Netherlands
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Valsecchi M, Ramadani J, Williams D, Galindo A, Jackson G. Influence of Tie-Molecules and Microstructure on the Fluid Solubility in Semicrystalline Polymers. J Phys Chem B 2022; 126:9059-9088. [DOI: 10.1021/acs.jpcb.2c04600] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Michele Valsecchi
- Department of Materials, Imperial College London, South Kensington Campus, LondonSW7 2AZ, U.K
- Department of Chemical Engineering, Imperial College London, South Kensington Campus, LondonSW7 2AZ, U.K
| | - Jona Ramadani
- Department of Chemical Engineering, Imperial College London, South Kensington Campus, LondonSW7 2AZ, U.K
| | - Daryl Williams
- Department of Chemical Engineering, Imperial College London, South Kensington Campus, LondonSW7 2AZ, U.K
| | - Amparo Galindo
- Department of Chemical Engineering, Imperial College London, South Kensington Campus, LondonSW7 2AZ, U.K
| | - George Jackson
- Department of Chemical Engineering, Imperial College London, South Kensington Campus, LondonSW7 2AZ, U.K
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Raheem H, Craster B, Seshia A. Analysis of Permeation and Diffusion Coefficients to Infer Aging Attributes in Polymers Subjected to Supercritical CO2 and H2 Gas at High Pressures. Polymers (Basel) 2022; 14:polym14183741. [PMID: 36145885 PMCID: PMC9502564 DOI: 10.3390/polym14183741] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2022] [Revised: 08/23/2022] [Accepted: 08/26/2022] [Indexed: 11/29/2022] Open
Abstract
There is a need to understand the permeation flux behavior of polymers exposed to high-pressure and -temperature fluids continuously for long time intervals. This study investigates evidence of structural alterations in polymer specimens as indicators of material aging through the monitoring of transport coefficients at pressure steps from 10 barg to 400 barg and temperatures ranging between 30 °C and 90 °C. The continuous flow permeation methodology is a well-established technique described in the literature for applications from membrane separation processes to polymeric pressure barriers used for complex fluid containment in the oil and gas industry. In this study, a novel methodology has been used that allows the permeating flux of supercritical CO2 and H2 gas through raised-temperature polyethylene and polyvinylidene fluoride films at varying elevated temperatures and pressures to be determined, over timescales of several months using gas chromatography. During these long-term measurements, changes in the test conditions, principally in temperature and stepwise increases in differential gas pressure, were made in order to determine the activation energy for permeation along with the transport coefficients of permeation, diffusion, and sorption. At no time was the polymer film allowed to outgas during the temperature or pressure alterations. The permeation experiments are complemented by differential scanning calorimetry tests to track changes in polymer crystallinity before and after exposure of the specimen to plasticizing gases, which revealed the extent of structural alterations inflicted on the specimen due to high temperature and pressure loads. It is seen that specimens that were exposed to starting high pressures aged more than those that had gradual increases in feed pressure. Furthermore, the relationship between transport coefficients and fractional free volume in the polymer upon exposure to high pressure and temperature conditions is explored. Lastly, the benefit of using fugacity in place of feed pressure for the calculation of the permeability coefficient is discussed. This study contributes to the understanding of the effect of prolonged exposure of the polymeric specimens to CO2 and H2 gas under stepwise pressure and temperature loading on their flux behaviors and crystallinity, and to candidate polyethylene-based specimens for oil field deployment.
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Affiliation(s)
- Hamad Raheem
- Department of Engineering, University of Cambridge, Trumpington St., Cambridge CB2 1PZ, UK
- Correspondence: (H.R.); (B.C.)
| | - Bernadette Craster
- Materials and Structural Integrity, TWI Ltd., Granta Park, Cambridge CB21 6AL, UK
- Correspondence: (H.R.); (B.C.)
| | - Ashwin Seshia
- Department of Engineering, University of Cambridge, Trumpington St., Cambridge CB2 1PZ, UK
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4
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Voyiatzis E, Stroeks A. Atomistic Modeling of Hydrogen and Oxygen Solubility in Semicrystalline PA-6 and HDPE Materials. J Phys Chem B 2022; 126:6102-6111. [PMID: 35921684 DOI: 10.1021/acs.jpcb.2c02854] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Hydrogen is a clean and sustainable energy carrier which plays a major role in the transition of the global energy market to a less fossil fuel dependent future. Polymer-based materials are crucial in the production, storage, transportation, and energy extraction of hydrogen. More insights in the hydrogen-polymers interactions are required to guide material design and product development, especially for hydrogen solubility in polymers, which is crucial in many applications. The current study aims at rationalizing the determining factors of hydrogen solubility in two relevant polymers: polyamide-6 (PA-6) and high density polyethylene (HDPE). Based on atomistic molecular dynamics simulations and experimental data, we have reached several conclusions related to hydrogen and oxygen solubility in these two polymers. The crystal phases of PA-6 and HDPE are impenetrable to hydrogen and oxygen at elevated pressures, despite the small molecular size of hydrogen and oxygen. The practical implication for gas barrier applications is that polymer crystals act as impermeable obstacles and gas migration takes place primarily in the amorphous phase. Experimental hydrogen and oxygen solubilities in PA-6 and HDPE at elevated pressures can be predicted in a semiquantitative manner by molecular simulations. The discrepancies between experimental and predicted values could be attributed to neglect of the effect of crystal regions on the amorphous polymer domains. Although hydrogen is smaller than oxygen, it has been experimentally observed that hydrogen has a lower solubility in PA-6 and HDPE than oxygen. This observation has been confirmed by molecular simulations and attributed to the more favorable energetic interactions of oxygen with PA-6 and PE than of hydrogen. These interactions dominate the solubility behavior over the distribution of the accessible volume in the polymers.
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Affiliation(s)
| | - Alexander Stroeks
- DSM Engineering Materials, Urmonderbaan 22, 6167 RD Geleen, The Netherlands
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Yang Y, Narayanan Nair AK, Sun S. Sorption and Diffusion of Methane, Carbon Dioxide, and Their Mixture in Amorphous Polyethylene at High Pressures and Temperatures. Ind Eng Chem Res 2021. [DOI: 10.1021/acs.iecr.0c06110] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Yafan Yang
- Physical Science and Engineering Division (PSE), Computational Transport Phenomena Laboratory, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Arun Kumar Narayanan Nair
- Physical Science and Engineering Division (PSE), Computational Transport Phenomena Laboratory, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Shuyu Sun
- Physical Science and Engineering Division (PSE), Computational Transport Phenomena Laboratory, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
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Permeation of a Range of Species through Polymer Layers under Varying Conditions of Temperature and Pressure: In Situ Measurement Methods. Polymers (Basel) 2019; 11:polym11061056. [PMID: 31212996 PMCID: PMC6630516 DOI: 10.3390/polym11061056] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Revised: 05/26/2019] [Accepted: 05/29/2019] [Indexed: 11/17/2022] Open
Abstract
Minimising the transport of corrosive reactants such as carbon dioxide, hydrogen sulfide and chloride ions to the surfaces of carbon steel pipes by the use of polymer barrier layers is of major interest in the oil and gas sector. In these applications, there is a requirement to assess the performance of these barrier layers although it is difficult to perform long-term predictions of barrier properties from the results of short-term measurements. New methodologies have been successfully developed to study the permeability of carbon dioxide (CO2) and hydrogen sulfide (H2S) through polymer layers under variable conditions of elevated temperatures of 100 °C and pressures of the order of 400 barg. In situ variation of the temperature and the inlet pressure of the gas (or gas mixture) allowed the activation energy and pressure dependence of the permeability to be determined without outgassing of the specimen. These methodologies have been applied to the measurement of the permeability of moulded polyphenylene sulfide (PPS) to supercritical CO2 in the presence of H2S. The diffusion coefficients of sodium chloride and potassium chloride through both PPS and polyether ether ketone (PEEK) at ambient temperature and pressure have also been measured.
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Lasich M, Ramjugernath D. Influence of fluorination on barrier properties of polymers: Insights from Monte Carlo simulations of eicosanes + methane. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2017; 40:12. [PMID: 28124765 DOI: 10.1140/epje/i2017-11501-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2016] [Accepted: 01/11/2017] [Indexed: 06/06/2023]
Abstract
Fluorination is widely used to improve the resistance and physical properties of polymers that are cheap to manufacture. This process improves the resistance properties of unfluorinated materials. This study examines the effects of varying the degree of fluorination on the clustering and absorption behaviour of methane n-eicosane. Monte Carlo simulations were performed for several different pressure values, at ambient temperature, to determine the uptake of methane into the eicosanes. The density of the pure eicosanes, simulated at ambient conditions, compared favourably with experimental data for the relevant polymers. The spatial configurations resulting from the absorption simulations were analysed to determine the clustering behaviour of absorbed methane. Both the prevalence of cluster formation in general, and the occurrence of specific cluster topologies of various sizes were considered. Cyclic clusters had a tendency to become more prevalent in unfluorinated eicosanes as the gas pressure was increased, while the presence of fluorine atoms on the eicosane backbone appeared to inhibit the formation of such clusters.
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Affiliation(s)
- Matthew Lasich
- Thermodynamics Research Unit, School of Engineering, University of KwaZulu-Natal, 4041, Durban, South Africa.
| | - Deresh Ramjugernath
- Thermodynamics Research Unit, School of Engineering, University of KwaZulu-Natal, 4041, Durban, South Africa
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Nieto-Draghi C, Fayet G, Creton B, Rozanska X, Rotureau P, de Hemptinne JC, Ungerer P, Rousseau B, Adamo C. A General Guidebook for the Theoretical Prediction of Physicochemical Properties of Chemicals for Regulatory Purposes. Chem Rev 2015; 115:13093-164. [PMID: 26624238 DOI: 10.1021/acs.chemrev.5b00215] [Citation(s) in RCA: 72] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Carlos Nieto-Draghi
- IFP Energies nouvelles , 1 et 4 avenue de Bois-Préau, 92852 Rueil-Malmaison, France
| | - Guillaume Fayet
- INERIS, Parc Technologique Alata, BP2 , 60550 Verneuil-en-Halatte, France
| | - Benoit Creton
- IFP Energies nouvelles , 1 et 4 avenue de Bois-Préau, 92852 Rueil-Malmaison, France
| | - Xavier Rozanska
- Materials Design S.A.R.L. , 18, rue de Saisset, 92120 Montrouge, France
| | - Patricia Rotureau
- INERIS, Parc Technologique Alata, BP2 , 60550 Verneuil-en-Halatte, France
| | | | - Philippe Ungerer
- Materials Design S.A.R.L. , 18, rue de Saisset, 92120 Montrouge, France
| | - Bernard Rousseau
- Laboratoire de Chimie-Physique, Université Paris Sud , UMR 8000 CNRS, Bât. 349, 91405 Orsay Cedex, France
| | - Carlo Adamo
- Institut de Recherche Chimie Paris, PSL Research University, CNRS, Chimie Paristech , 11 rue P. et M. Curie, F-75005 Paris, France.,Institut Universitaire de France , 103 Boulevard Saint Michel, F-75005 Paris, France
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9
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Villanueva N, Flaconnèche B, Creton B. Prediction of Alternative Gasoline Sorption in a Semicrystalline Poly(ethylene). ACS COMBINATORIAL SCIENCE 2015; 17:631-40. [PMID: 26348289 DOI: 10.1021/acscombsci.5b00094] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In this work, we first report the acquisition of new experimental data and then the development of quantitative structure-property relationships on the basis of sorption values for neat compounds and up to quinary mixtures of some hydrocarbons, alcohols, and ethers, in a semicrystalline poly(ethylene). Two machine learning methods (i.e., genetic function approximation and support vector machines) and two families of descriptors (i.e., functional group counts and substructural molecular fragments) were used to derive predictive models. Models were then used to predict sorption variations when increasing the number of carbon atoms in a series of hydrocarbons and for n-alkan-1-ols. In addition to the performed internal/external validations, the model was further tested for surrogate gasolines containing ca. 300 compounds, and predicted sorption values were in excellent agreement with experimental data (R(2) = 0.940).
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Affiliation(s)
- Nicolas Villanueva
- IFP Energies nouvelles, 1
et 4 avenue de Bois-Préau, 92852 Rueil-Malmaison, France
| | - Bruno Flaconnèche
- IFP Energies nouvelles, 1
et 4 avenue de Bois-Préau, 92852 Rueil-Malmaison, France
| | - Benoit Creton
- IFP Energies nouvelles, 1
et 4 avenue de Bois-Préau, 92852 Rueil-Malmaison, France
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10
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Influence of high pressures on CH4, CO2 and H2S solubility in polyethylene: Experimental and molecular simulation approaches for pure gas and gas mixtures. Modelling of the sorption isotherms. J Memb Sci 2015. [DOI: 10.1016/j.memsci.2015.04.040] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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11
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Chmelař J, Smolná K, Haškovcová K, Podivinská M, Maršálek J, Kosek J. Equilibrium sorption of ethylene in polyethylene: Experimental study and PC-SAFT simulations. POLYMER 2015. [DOI: 10.1016/j.polymer.2015.01.012] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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12
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Lachet V, Teuler JM, Rousseau B. Classical force field for hydrofluorocarbon molecular simulations. Application to the study of gas solubility in poly(vinylidene fluoride). J Phys Chem A 2014; 119:140-51. [PMID: 25479370 DOI: 10.1021/jp506895p] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
A classical all-atoms force field for molecular simulations of hydrofluorocarbons (HFCs) has been developed. Lennard-Jones force centers plus point charges are used to represent dispersion-repulsion and electrostatic interactions. Parametrization of this force field has been performed iteratively using three target properties of pentafluorobutane: the quantum energy of an isolated molecule, the dielectric constant in the liquid phase, and the compressed liquid density. The accuracy and transferability of this new force field has been demonstrated through the simulation of different thermophysical properties of several fluorinated compounds, showing significant improvements compared to existing models. This new force field has been applied to study solubilities of several gases in poly(vinylidene fluoride) (PVDF) above the melting temperature of this polymer. The solubility of CH4, CO2, H2S, H2, N2, O2, and H2O at infinite dilution has been computed using test particle insertions in the course of a NpT hybrid Monte Carlo simulation. For CH4, CO2, and their mixtures, some calculations beyond the Henry regime have also been performed using hybrid Monte Carlo simulations in the osmotic ensemble, allowing both swelling and solubility determination. An ideal mixing behavior is observed, with identical solubility coefficients in the mixtures and in pure gas systems.
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Affiliation(s)
- V Lachet
- IFP Energies nouvelles, 1-4 Avenue de Bois-Préau, 92852 Rueil-Malmaison, France
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Nie F, He G, Liu Y, Zhao W, Ju J. Influences of van der waals volume of substitute groups on CO2permselectivity of polyimide-A molecular simulation study. J Appl Polym Sci 2014. [DOI: 10.1002/app.41082] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Fei Nie
- State Key Laboratory of Fine Chemicals; Research and Development Center of Membrane Science and Technology; School of Chemical Engineering; Dalian University of Technology; 2 Linggong Road Dalian 116024 China
| | - Gaohong He
- State Key Laboratory of Fine Chemicals; Research and Development Center of Membrane Science and Technology; School of Chemical Engineering; Dalian University of Technology; 2 Linggong Road Dalian 116024 China
| | - Yuanfa Liu
- State Key Laboratory of Fine Chemicals; Research and Development Center of Membrane Science and Technology; School of Chemical Engineering; Dalian University of Technology; 2 Linggong Road Dalian 116024 China
| | - Wei Zhao
- State Key Laboratory of Fine Chemicals; Research and Development Center of Membrane Science and Technology; School of Chemical Engineering; Dalian University of Technology; 2 Linggong Road Dalian 116024 China
| | - Jia Ju
- State Key Laboratory of Fine Chemicals; Research and Development Center of Membrane Science and Technology; School of Chemical Engineering; Dalian University of Technology; 2 Linggong Road Dalian 116024 China
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Eslami H, Kesik M, Karimi-Varzaneh HA, Müller-Plathe F. Sorption and diffusion of carbon dioxide and nitrogen in poly(methyl methacrylate). J Chem Phys 2014; 139:124902. [PMID: 24089799 DOI: 10.1063/1.4821585] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Molecular dynamics simulations are performed to determine the solubility and diffusion coefficient of carbon dioxide and nitrogen in poly(methyl methacrylate) (PMMA). The solubilities of CO2 in the polymer are calculated employing our grand canonical ensemble simulation method, fixing the target excess chemical potential of CO2 in the polymer and varying the number of CO2 molecules in the polymer matrix till establishing equilibrium. It is shown that the calculated sorption isotherms of CO2 in PMMA, employing this method well agrees with experiment. Our results on the diffusion coefficients of CO2 and N2 in PMMA are shown to obey a common hopping mechanism. It is shown that the higher solubility of CO2 than that of N2 is a consequence of more attractive interactions between the carbonyl group of polymer and the sorbent. While the residence time of CO2 beside the carbonyl group of polymer is about three times higher than that of N2, the diffusion coefficient of CO2 in PMMA is higher than that of N2. The higher diffusion coefficient of CO2, compared to N2, in PMMA is shown to be due to the higher (≈3 times) swelling of polymer upon CO2 uptake.
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Affiliation(s)
- Hossein Eslami
- Department of Chemistry, College of Sciences, Persian Gulf University, Boushehr 75168, Iran
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15
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Golzar K, Amjad-Iranagh S, Amani M, Modarress H. Molecular simulation study of penetrant gas transport properties into the pure and nanosized silica particles filled polysulfone membranes. J Memb Sci 2014. [DOI: 10.1016/j.memsci.2013.09.056] [Citation(s) in RCA: 75] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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16
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Factors influencing properties of interfacial regions in semicrystalline polyethylene: A molecular dynamics simulation study. POLYMER 2013. [DOI: 10.1016/j.polymer.2013.04.067] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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