1
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Lightweight, low-shrinkage and high elastic poly(butylene adipate-co-terephthalate) foams achieved by microcellular foaming using N2 & CO2 as co-blowing agents. J CO2 UTIL 2022. [DOI: 10.1016/j.jcou.2022.102149] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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2
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Lee JH, Mahmood SH, Pin JM, Li R, Lee PC, Park CB. Determination of CO 2 solubility in semi-crystalline polylactic acid with consideration of rigid amorphous fraction. Int J Biol Macromol 2022; 204:274-283. [PMID: 35120942 DOI: 10.1016/j.ijbiomac.2022.01.182] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Revised: 01/26/2022] [Accepted: 01/28/2022] [Indexed: 11/26/2022]
Abstract
Due to phase heterogeneity in semi-crystalline polymers, accurate determination of gas solubility has been a challenge. In this regard, PLA/CO2 was used as a case study to investigate the parameters governing formation of the rigid amorphous fraction (RAF) and its effect on the gas sorption behavior of the polymer. Six samples with different degrees of RAF were prepared through varying PLA tacticity and thermal history. Then, a gravimetric method involving a magnetic suspension balance and an in-house PVT visualization system was employed to experimentally determine the CO2 solubility at 70 °C under a pressure of 4.5 MPa. Furthermore, a theoretical CO2 solubility was calculated based on the Simha-Somcynski equation of state and was used in conjunction with the two-phase and three-phase models to describe the phase dependency of the gas solubility. The conventional two-phase model that considered the bulk amorphous phase consistently over-approximated the CO2 solubility compared to the measured data. On the other hand, the three-phase model that distinguished the rigid and the mobile amorphous phases well represented the experimental result. The analysis yielded CO2 solubility coefficients of 0.0375 ggas/gpoly for the RAF and 0.0817 ggas/gpoly for the mobile counterpart.
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Affiliation(s)
- Jung H Lee
- Department of Mechanical and Industrial Engineering, University of Toronto, 5 King's College Road, Toronto M5S 3G8, Canada
| | - S Hassan Mahmood
- Department of Mechanical and Industrial Engineering, University of Toronto, 5 King's College Road, Toronto M5S 3G8, Canada
| | - Jean-Mathieu Pin
- Department of Mechanical and Industrial Engineering, University of Toronto, 5 King's College Road, Toronto M5S 3G8, Canada
| | - Ruosong Li
- Department of Mechanical and Industrial Engineering, University of Toronto, 5 King's College Road, Toronto M5S 3G8, Canada
| | - Patrick C Lee
- Department of Mechanical and Industrial Engineering, University of Toronto, 5 King's College Road, Toronto M5S 3G8, Canada
| | - Chul B Park
- Department of Mechanical and Industrial Engineering, University of Toronto, 5 King's College Road, Toronto M5S 3G8, Canada.
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3
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Hu D, Gao X, Qiang W, Cui L, Xu Z, Zhao L. Formation mechanism of bi-modal cell structure polystyrene foams by synergistic effect of CO2-philic additive and co-blowing agent. J Supercrit Fluids 2022. [DOI: 10.1016/j.supflu.2021.105498] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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4
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Breuer R, Hendriks S, Reinhardt N, Facklam M, Hopmann C. Modeling flow and cell formation in foam sheet extrusion of polystyrene with
CO
2
and co‐blowing agents. Part I: Material model. POLYM ENG SCI 2021. [DOI: 10.1002/pen.25800] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Robert Breuer
- Institute for Plastics Processing (IKV) in Industry and Craft at RWTH Aachen University Aachen Germany
| | - Sven Hendriks
- Institute for Plastics Processing (IKV) in Industry and Craft at RWTH Aachen University Aachen Germany
| | - Nicolas Reinhardt
- Institute for Plastics Processing (IKV) in Industry and Craft at RWTH Aachen University Aachen Germany
| | - Martin Facklam
- Institute for Plastics Processing (IKV) in Industry and Craft at RWTH Aachen University Aachen Germany
| | - Christian Hopmann
- Institute for Plastics Processing (IKV) in Industry and Craft at RWTH Aachen University Aachen Germany
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5
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Effect of alcohols-regulated crystallization on foaming process and cell morphology of polypropylene. J Supercrit Fluids 2021. [DOI: 10.1016/j.supflu.2021.105271] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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6
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Enhancement of Lipid Extraction from Soya Bean by Addition of Dimethyl Ether as Entrainer into Supercritical Carbon Dioxide. Foods 2021; 10:foods10061223. [PMID: 34071290 PMCID: PMC8229543 DOI: 10.3390/foods10061223] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 05/19/2021] [Accepted: 05/27/2021] [Indexed: 11/17/2022] Open
Abstract
Soya beans contain a variety of lipids, and it is important to selectively separate neutral lipids from other lipids. Supercritical carbon dioxide extraction has been used as an alternative to the selective separation of neutral lipids from soya beans, usually using non-polar hexane. However, supercritical carbon dioxide extraction has a high operating pressure of over 40 MPa. On the other hand, liquefied dimethyl ether extraction, which has attracted attention in recent years, requires an operating pressure of only 0.5 MPa, but there is concern about the possibility of an explosion during operation because it is a flammable liquefied gas. Therefore, this study aims to reduce the operating pressure by using a non-flammable solvent, supercritical carbon dioxide extraction mixed with liquefied dimethyl ether as an entrainer. The extraction rate and the amount of neutral lipids extracted increased with increasing amounts of added liquefied dimethyl ether. In the mixed solvent, the amount of neutral lipids extracted was higher at an operating pressure of 20 MPa than in pure supercritical carbon dioxide extraction at 40 MPa. The mixing of liquefied dimethyl ether with supercritical carbon dioxide allowed an improvement in the extraction of neutral lipids while remaining non-flammable.
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7
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Alam H, Park CB, Thompson RB. An off-lattice model of the Sanchez-Lacombe Eq. of state for polymers with finite flexibility. POLYMER 2021. [DOI: 10.1016/j.polymer.2020.123334] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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8
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Zhao C, Mark LH, Kim S, Chang E, Park CB, Lee PC. Recent progress in micro‐/nano‐fibrillar reinforced polymeric composite foams. POLYM ENG SCI 2021. [DOI: 10.1002/pen.25643] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Chongxiang Zhao
- Department of Mechanical and Industrial Engineering University of Toronto Toronto Ontario Canada
| | - Lun Howe Mark
- Department of Mechanical and Industrial Engineering University of Toronto Toronto Ontario Canada
| | - Sundong Kim
- Department of Mechanical and Industrial Engineering University of Toronto Toronto Ontario Canada
| | - Eunse Chang
- Department of Mechanical and Industrial Engineering University of Toronto Toronto Ontario Canada
| | - Chul B. Park
- Department of Mechanical and Industrial Engineering University of Toronto Toronto Ontario Canada
| | - Patrick C. Lee
- Department of Mechanical and Industrial Engineering University of Toronto Toronto Ontario Canada
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9
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Babacic V, Varghese J, Coy E, Kang E, Pochylski M, Gapinski J, Fytas G, Graczykowski B. Mechanical reinforcement of polymer colloidal crystals by supercritical fluids. J Colloid Interface Sci 2020; 579:786-793. [PMID: 32673855 DOI: 10.1016/j.jcis.2020.06.104] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 06/19/2020] [Accepted: 06/24/2020] [Indexed: 01/21/2023]
Abstract
Colloidal crystals realized by self-assembled polymer nanoparticles have prominent attraction as a platform for various applications from assembling photonic and phononic crystals, acoustic metamaterials to coating applications. However, the fragility of these systems limits their application horizon. In this work the uniform mechanical reinforcement and tunability of 3D polystyrene colloidal crystals by means of cold soldering are reported. This structural strengthening is achieved by high pressure gas (N2 or Ar) plasticization at temperatures well below the glass transition. Brillouin light scattering is employed to monitor in-situ the mechanical vibrations of the crystal and thereby determine preferential pressure, temperature and time ranges for soldering, i.e. formation of physical bonding among the nanoparticles while maintaining the shape and translational order. This low-cost method is potentially useful for fabrication and tuning of durable devices including applications in photonics, phononics, acoustic metamaterials, optomechanics, surface coatings and nanolithography.
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Affiliation(s)
- Visnja Babacic
- Faculty of Physics, Adam Mickiewicz University, Uniwersytetu Poznanskiego 2, 61-614 Poznan, Poland
| | - Jeena Varghese
- Faculty of Physics, Adam Mickiewicz University, Uniwersytetu Poznanskiego 2, 61-614 Poznan, Poland
| | - Emerson Coy
- NanoBioMedical Centre, Adam Mickiewicz University, Wszechnicy Piastowskiej 3, 61-614 Poznan, Poland
| | - Eunsoo Kang
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Mikolaj Pochylski
- Faculty of Physics, Adam Mickiewicz University, Uniwersytetu Poznanskiego 2, 61-614 Poznan, Poland
| | - Jacek Gapinski
- Faculty of Physics, Adam Mickiewicz University, Uniwersytetu Poznanskiego 2, 61-614 Poznan, Poland
| | - George Fytas
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Bartlomiej Graczykowski
- Faculty of Physics, Adam Mickiewicz University, Uniwersytetu Poznanskiego 2, 61-614 Poznan, Poland; Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany.
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10
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Qiang W, Zhao L, Liu T, Liu Z, Gao X, Hu D. Systematic study of alcohols based co-blowing agents for polystyrene foaming in supercritical CO2: Toward the high efficiency of foaming process and foam structure optimization. J Supercrit Fluids 2020. [DOI: 10.1016/j.supflu.2019.104718] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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11
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Abstract
Injection moulding is a well-established replication process for the cost-effective manufacture of polymer-based components. The process has different applications in fields such as medical, automotive and aerospace. To expand the use of polymers to meet growing consumer demands for increased functionality, advanced injection moulding processes have been developed that modifies the polymer to create microcellular structures. Through the creation of microcellular materials, additional functionality can be gained through polymer component weight and processing energy reduction. Microcellular injection moulding shows high potential in creating innovation green manufacturing platforms. This review article aims to present the significant developments that have been achieved in different aspects of microcellular injection moulding. Aspects covered include core-back, gas counter pressure, variable thermal tool moulding and other advanced technologies. The resulting characteristics of creating microcellular injection moulding components through both plasticising agents and nucleating agents are presented. In addition, the article highlights potential areas for research exploitation. In particular, acoustic and thermal applications, nano-cellular injection moulding parts and developments of more accurate simulations.
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Affiliation(s)
| | - Andrew Rees
- College of Engineering, Swansea University, Swansea, UK
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12
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Li R, Lee JH, Wang C, Howe Mark L, Park CB. Solubility and diffusivity of CO2 and N2 in TPU and their effects on cell nucleation in batch foaming. J Supercrit Fluids 2019. [DOI: 10.1016/j.supflu.2019.104623] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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13
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Effects of Gas Adsorption on the Mechanical Properties of Amorphous Polymer. Polymers (Basel) 2019; 11:polym11050817. [PMID: 31067699 PMCID: PMC6572250 DOI: 10.3390/polym11050817] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2019] [Revised: 04/12/2019] [Accepted: 05/05/2019] [Indexed: 11/26/2022] Open
Abstract
This study investigates the properties of a polymer–gas mixture formed through diffusion, based on the changes in the partial pressure and observed changes in the impact and tensile strengths owing to the gas dissolution. The high-pressure gas dissolves into a solid-state polymer through diffusion based on the difference in the partial pressure. This dissolved gas is present in the amorphous region within the polymeric material temporarily, which results in the polymer exhibiting different mechanical properties, while the gas remains dissolved in the polymer. In this study, the mechanical properties of amorphous polyethylene terephthalate (APET) specimens prepared by dissolving CO2 using a high-pressure vessel were investigated, and the resulting impact and tensile strengths were measured. These experiments showed that the increase in sorption rate of CO2 caused an increase in the impact strength. At 2.9% CO2 absorption, the impact strength of APET increased 956% compared to that of the reference specimen. Furthermore, the tensile strength decreased by up to 71.7% at 5.48% CO2 sorption; the stress–strain curves varied with the gas sorption rate. This phenomenon can be associated with the change in the volume caused by CO2 dissolution. When the APET absorbed more than 2.0% CO2 gas, sample volume increased. A decrease in the network density can occur when the volume is increased while maintaining constant mass. The CO2 gas in the polymer acted as a cushion in impact tests which have sorption rates above 2%. In addition to the reduction in the network density in the polymer chain, Van Der Waals forces are decreased causing a decrease in tensile strength only while CO2 is present in the APET. These observations only occur prior to CO2 desorption from the polymer.
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14
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von Konigslow K, Park CB, Thompson RB. Application of a constant hole volume Sanchez-Lacombe equation of state to mixtures relevant to polymeric foaming. SOFT MATTER 2018; 14:4603-4614. [PMID: 29786729 DOI: 10.1039/c8sm00794b] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
A variant of the Sanchez-Lacombe equation of state is applied to several polymers, blowing agents, and saturated mixtures of interest to the polymer foaming industry. These are low-density polyethylene-carbon dioxide and polylactide-carbon dioxide saturated mixtures as well as polystyrene-carbon dioxide-dimethyl ether and polystyrene-carbon dioxide-nitrogen ternary saturated mixtures. Good agreement is achieved between theoretically predicted and experimentally determined solubilities, both for binary and ternary mixtures. Acceptable agreement with swelling ratios is found with no free parameters. Up-to-date pure component Sanchez-Lacombe characteristic parameters are provided for carbon dioxide, dimethyl ether, low-density polyethylene, nitrogen, polylactide, linear and branched polypropylene, and polystyrene. Pure fluid low-density polyethylene and nitrogen parameters exhibit more moderate success while still providing acceptable quantitative estimations. Mixture estimations are found to have more moderate success where pure components are not as well represented. The Sanchez-Lacombe equation of state is found to correctly predict the anomalous reversal of solubility temperature dependence for low critical point fluids through the observation of this behaviour in polystyrene nitrogen mixtures.
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Affiliation(s)
- Kier von Konigslow
- Department of Physics & Astronomy and Waterloo Institute for Nanotechnology, University of Waterloo, 200 University Avenue West, Waterloo, Ontario N2L 3G1, Canada.
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15
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Hendriks S, Hopmann C, Zepnik S. Extrusion foaming of thermoplastic cellulose acetate sheets with HFO-1234ze and co-blowing agents. POLYM ENG SCI 2018. [DOI: 10.1002/pen.24850] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Sven Hendriks
- Institute of Plastics Processing (IKV); RWTH Aachen University; 52074 Aachen Germany
| | - Christian Hopmann
- Institute of Plastics Processing (IKV); RWTH Aachen University; 52074 Aachen Germany
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16
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Shaayegan V, Wang C, Costa F, Han S, Park CB. Effect of the melt compressibility and the pressure drop rate on the cell-nucleation behavior in foam injection molding with mold opening. Eur Polym J 2017. [DOI: 10.1016/j.eurpolymj.2017.05.003] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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17
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Effect of foam processing parameters on bubble nucleation and growth dynamics in high-pressure foam injection molding. Chem Eng Sci 2016. [DOI: 10.1016/j.ces.2016.07.040] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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