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Magnetic Field in Polymer Research

A special issue of Polymers (ISSN 2073-4360).

Deadline for manuscript submissions: closed (10 December 2018) | Viewed by 65129

Special Issue Editors


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Guest Editor
Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan
Interests: magneto science; X-ray diffraction; solid-state NMR; cellulose nano crystal; actuator; chirality

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Guest Editor
Department of Applied Chemistry, Tokyo Metropolitan University, 1-1 Minami-ohsawa, Hachioji, Tokyo 192-0397, Japan
Interests: higher order structure of polymer; composite materials; magnetic alignment of feeble magnetic materials, NMR spectroscopy

Special Issue Information

Dear Colleagues,

Most polymers, including commercial synthetic polymers, and biopolymers such as proteins, DNAs and polysaccharides, are non-magnetic materials and considered to be indifferent to magnetic fields.  However, they are in fact magnetized, though weakly (they are diamagnetic), and thus, they can respond to an applied magnetic field. This magnetic response of polymers can be utilized for polymer processing.  For example, polymeric particles (e.g., polystyrene and polypropylene) can be separated by using the difference in their magnetic susceptibilities; polymeric fibers that are nano- to micrometers in size can be aligned owing to their magnetic anisotropy; small polymeric particles can be manipulated into a designed pattern under spatially modulated magnetic fields; and magnetic fields can encourage the formation of microstructures of block copolymers. All of these phenomena are well known only to a limited number of polymer scientists despite their high potential in many polymer processing applications, while polymer composites, gels and elastomers containing magnetic particles are relatively well recognized. 

This Special Issue is aimed at documenting recent advances in the use of magnetic fields for polymer processing and fabrication of functional polymeric systems. Both original papers and communications are welcome, including but not limited to those on the use of magnetic force and torque for the processing of polymeric systems. 

Prof. Tsunehisa Kimura
Prof. Masafumi Yamato
Guest Editors

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Keywords

  • magnetic orientation
  • magnetic levitation and separation
  • magnetic patterning and manipulation
  • magnetorheology
  • phase separation under magnetic fields
  • magnetic nanoparticle
  • block copolymers
  • biopolymers
  • graphene
  • nanotubes

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Published Papers (12 papers)

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12 pages, 1775 KiB  
Article
Controlled Preparation of Thermally Stable Fe-Poly(dimethylsiloxane) Composite by Magnetic Induction Heating
by Laila M. Al-Harbi, Mohamed S. A. Darwish, Manal M. Khowdiary and Ivan Stibor
Polymers 2018, 10(5), 507; https://doi.org/10.3390/polym10050507 - 7 May 2018
Cited by 20 | Viewed by 4806
Abstract
The most challenging task in the preparation of poly(dimethylsiloxane) composites is to control the curing time as well as to enhance their thermal and swelling behavior. Curing rate can be modified and controlled by a range of iron powder contents to achieve a [...] Read more.
The most challenging task in the preparation of poly(dimethylsiloxane) composites is to control the curing time as well as to enhance their thermal and swelling behavior. Curing rate can be modified and controlled by a range of iron powder contents to achieve a desired working time, where iron is used as self-heating particles. Iron under alternative current magnetic field (ACMF) is able to generate thermal energy, providing a benefit in accelerating the curing of composites. Three types of iron-Poly(dimethylsiloxane) (Fe-PDMS) composites were prepared under ACMF with iron content 5, 10, and 15 wt %. The curing process was investigated by FTIR, while the morphology and the thermal stability were examined by SEM, DMA, and TGA. The heating’s profile was studied as functions of iron content and induction time. It was found that the time required to complete curing was reduced and the curing temperature was controlled by varying the iron content and induction time. In addition, the thermal stability and the swelling behavior of the prepared composites were enhanced in comparison with the conventional PDMS and thus offer a promising route to obtain thermally stable composites. Full article
(This article belongs to the Special Issue Magnetic Field in Polymer Research)
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14 pages, 3980 KiB  
Article
Crystal Orientation of Poly(l-Lactic Acid) Induced by Magnetic Alignment of a Nucleating Agent
by Ryosuke Kusumi, Sachi Teranishi, Fumiko Kimura, Masahisa Wada, Tsunehisa Kimura, Yoshiki Horikawa and Takahiko Kawai
Polymers 2018, 10(6), 653; https://doi.org/10.3390/polym10060653 - 11 Jun 2018
Cited by 7 | Viewed by 5792
Abstract
The orientation of poly(l-lactic acid) (PLLA) crystals was controlled through crystal growth from a magnetically oriented nucleating agent, phenylphosphonic acid zinc (PPAZn). The one-dimensional magnetically oriented microcrystal array of PPAZn microcrystals revealed the relationship between the magnetization and crystallographic axes in [...] Read more.
The orientation of poly(l-lactic acid) (PLLA) crystals was controlled through crystal growth from a magnetically oriented nucleating agent, phenylphosphonic acid zinc (PPAZn). The one-dimensional magnetically oriented microcrystal array of PPAZn microcrystals revealed the relationship between the magnetization and crystallographic axes in the PPAZn crystal. The PPAZn microcrystals were homogeneously dispersed in PLLA via melt mixing, which decreased the molecular weight of the PLLA component due to degradation. The PPAZn microcrystals in the molten PLLA were uniaxially aligned under an 8-T static or rotating magnetic field. The wide-angle X-ray diffraction and small-angle X-ray scattering patterns of the PPAZn/PLLA composite films crystallized under each magnetic field showed that the PLLA lamellae grew from the surface of the PPAZn microcrystals, which were uniaxially oriented along the easy- or hard-magnetization axis, with the c-axis of PLLA parallel to the bc-plane of PPAZn. It was also suggested that the greater nucleating effect of PPAZn on PLLA was derived not from geometrical matching, but from factors such as favorable interactions and/or the plate-like shape of the microcrystal. Full article
(This article belongs to the Special Issue Magnetic Field in Polymer Research)
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9 pages, 3619 KiB  
Article
Preparation of Crystallites for Oriented Poly(Lactic Acid) Films Using a Casting Method under a Magnetic Field
by Shuta Hara, Shuto Watanabe, Kohki Takahashi, Shigeru Shimizu and Hiroki Ikake
Polymers 2018, 10(10), 1083; https://doi.org/10.3390/polym10101083 - 29 Sep 2018
Cited by 10 | Viewed by 5301
Abstract
Poly-l-lactic acid (PLLA) has biocompatibility and unique characteristics such as piezoelectric properties. This attracts attention not only in the environmental field but also in the biomedical and electronic materials fields. In recent years, the literature about orienting PLLA crystals has been [...] Read more.
Poly-l-lactic acid (PLLA) has biocompatibility and unique characteristics such as piezoelectric properties. This attracts attention not only in the environmental field but also in the biomedical and electronic materials fields. In recent years, the literature about orienting PLLA crystals has been promoting new applications for PLLA such as high strength fiberization and piezoelectric properties. This paper presents a new technique to orient the PLLA crystalline through casting under magnetic irradiation. The advantage of this technique is that it is possible to radiate the magnetic field to the PLLA crystalline in an extremely low viscosity environment. Moreover, the heat treatment condition was optimized in order to improve the low crystallinity of casting, and it succeeded in producing a PLLA film with a high degree of orientation and high crystallinity. Furthermore, PLLA/1-butyl-3-methylimidazolium dibutylphosphate (bmimjdbp) composite films were prepared under the same conditions, and this also succeeded in the further improvement of crystallinity. Full article
(This article belongs to the Special Issue Magnetic Field in Polymer Research)
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13 pages, 5689 KiB  
Article
An Electrochemical Sensor for Diphenylamine Detection Based on Reduced Graphene Oxide/Fe3O4-Molecularly Imprinted Polymer with 1,4-Butanediyl-3,3′-bis-l-vinylimidazolium Dihexafluorophosphate Ionic Liquid as Cross-Linker
by Lingyu Liu, Xudong Zhu, Yanbo Zeng, Hailong Wang, Yixia Lu, Jian Zhang, Zhengzhi Yin, Zhidong Chen, Yiwen Yang and Lei Li
Polymers 2018, 10(12), 1329; https://doi.org/10.3390/polym10121329 - 1 Dec 2018
Cited by 42 | Viewed by 4980
Abstract
In this paper, we report a new composite of reduced graphene oxide/Fe3O4-ionic liquid based molecularly imprinted polymer (RGO/Fe3O4-IL-MIP) fabricated for diphenylamine (DPA) detection. RGO/Fe3O4-IL-MIP was prepared with RGO/Fe3O4 [...] Read more.
In this paper, we report a new composite of reduced graphene oxide/Fe3O4-ionic liquid based molecularly imprinted polymer (RGO/Fe3O4-IL-MIP) fabricated for diphenylamine (DPA) detection. RGO/Fe3O4-IL-MIP was prepared with RGO/Fe3O4 as supporter, ionic liquid 1-vinyl-3-butylimidazolium hexafluorophosphate ([VC4mim][PF6]) as functional monomer, ionic liquid 1,4-butanediyl-3,3’-bis-l-vinylimidazolium dihexafluorophosphate ([V2C4(mim)2][(PF6)2]) as cross-linker, and diphenylamine (DPA) as template molecule. Fourier transform infrared spectroscopy, thermal gravimetric analysis, scanning electron microscopy, and vibrating sample magnetometer were employed to characterize the RGO/Fe3O4-IL-MIP composite. RGO/Fe3O4-IL-MIP was then drop-cast onto a glassy carbon electrode to construct an electrochemical sensor for DPA. The differential pulse voltammetry (DPV) peak current response for 20 μM DPA of RGO/Fe3O4-IL-MIP modified glassy carbon electrode (GCE) was 3.24 and 1.68 times that of RGO/Fe3O4-IL-NIP and RGO/Fe3O4-EGDMA-MIP modified GCEs, respectively, indicating the advantage of RGO/Fe3O4-IL-MIP based on ionic liquid (IL) as a cross-linker. The RGO/Fe3O4-IL-MIP sensor demonstrated good recognition for DPA. Under the optimized conditions, the RGO/Fe3O4-IL-MIP sensor exhibited a DPA detection limit of 0.05 μM (S/N = 3) with a linear range of 0.1–30 μM. Moreover, the new RGO/Fe3O4-IL-MIP based sensor detected DPA in real samples with satisfactory results. Full article
(This article belongs to the Special Issue Magnetic Field in Polymer Research)
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7 pages, 1500 KiB  
Communication
Railway Actuator Made of Magnetic Elastomers and Driven by a Magnetic Field
by Yasuhiro Umehara, Yusuke Yamanaga, Shota Akama, Shunsuke Kato, Shogo Kamoshita, Mika Kawai and Tetsu Mitsumata
Polymers 2018, 10(12), 1351; https://doi.org/10.3390/polym10121351 - 6 Dec 2018
Cited by 12 | Viewed by 3126
Abstract
We fabricated a mono-link using bimodal magnetic elastomers that demonstrate drastic changes in the elastic modulus by magnetic fields. The magnetic elastomer is bimodal consisting of large magnetic particles and nonmagnetic fine particles. The storage modulus for bimodal magnetic elastomers was altered from [...] Read more.
We fabricated a mono-link using bimodal magnetic elastomers that demonstrate drastic changes in the elastic modulus by magnetic fields. The magnetic elastomer is bimodal consisting of large magnetic particles and nonmagnetic fine particles. The storage modulus for bimodal magnetic elastomers was altered from 2.2 × 105 to 1.7 × 106 Pa by a magnetic field of 500 mT. Compression tests up to a strain of 20% also revealed that the on-field stress for the bimodal magnetic elastomer was 1.24 times higher than the off-field stress. The bimodal magnetic elastomer was synthesized for the mono-link and was mounted on the bogie of a railway vehicle. A running test exhibited that the wheel lateral force was reduced by 20% by applying a magnetic field of 390 mT. Full article
(This article belongs to the Special Issue Magnetic Field in Polymer Research)
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16 pages, 5897 KiB  
Article
β-Cyclodextrin–Hyaluronic Acid Polymer Functionalized Magnetic Graphene Oxide Nanocomposites for Targeted Photo-Chemotherapy of Tumor Cells
by Wenting Liang, Yu Huang, Dongtao Lu, Xuewen Ma, Tao Gong, Xiaodong Cui, Baofeng Yu, Cheng Yang, Chuan Dong and Shaomin Shuang
Polymers 2019, 11(1), 133; https://doi.org/10.3390/polym11010133 - 14 Jan 2019
Cited by 62 | Viewed by 7938
Abstract
A multifunctional targeted drug delivery platform (CDHA–MGO) has been successfully constructed by grafting β-cyclodextrin–hyaluronic acid polymers (CDHA) to Fe3O4–graphene oxide (MGO). The obtained CDHA–MGO nanocomposite has good water-dispersibility, easy magnetic separation, high near-infrared (NIR) photothermal heating, and excellent biocompatibility. [...] Read more.
A multifunctional targeted drug delivery platform (CDHA–MGO) has been successfully constructed by grafting β-cyclodextrin–hyaluronic acid polymers (CDHA) to Fe3O4–graphene oxide (MGO). The obtained CDHA–MGO nanocomposite has good water-dispersibility, easy magnetic separation, high near-infrared (NIR) photothermal heating, and excellent biocompatibility. The β-cyclodextrin-hyaluronic acid polymers efficaciously enhance the doxorubicin (DOX) loading amount up to 485.43 mg·g−1. Meanwhile, the Fe3O4–graphene oxide provides a facile photothermal response mechanism to handle the NIR-triggered release of DOX in weak acidic solvent environments. Significantly, the DOX-loaded nanocomposite (DOX@CDHA–MGO) has displayed CD44 receptor-mediated active targeting recognition and chemo-photothermal synergistic therapy of hepatoma cells. These findings suggest that the as-prepared drug delivery platform would be of valuable potential for cancer-targeted photo-chemotherapy. Full article
(This article belongs to the Special Issue Magnetic Field in Polymer Research)
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17 pages, 4913 KiB  
Article
Syntheses, Structures, and Magnetic Properties of a Series of Heterotri-, Tetra- and Pentanuclear LnIII–CoII Compounds
by Yun Xu, Feng Luo and Ji-Min Zheng
Polymers 2019, 11(2), 196; https://doi.org/10.3390/polym11020196 - 23 Jan 2019
Cited by 6 | Viewed by 3127
Abstract
Three types of Ln(III)–Co(II) heterometallic compounds, LnCo2(L1)7(bipy)2 (Ln = Pr-1, Eu-2, Sm-3, Gd-4, Tb-5, Dy-6) (L1 = 4-chlorobenzoate, bipy = 2,2′-bipyridine), Ln2Co2(L [...] Read more.
Three types of Ln(III)–Co(II) heterometallic compounds, LnCo2(L1)7(bipy)2 (Ln = Pr-1, Eu-2, Sm-3, Gd-4, Tb-5, Dy-6) (L1 = 4-chlorobenzoate, bipy = 2,2′-bipyridine), Ln2Co2(L2)10(bipy)2 (Ln = Sm-7, Gd-8, Tb-9, Dy-10, Ho-11, Er-12, Yb-13), (L2 = 2,4-dichlorobenzoate, bipy = 2,2′-bipyridine, phen = 1,10-phenanthroline), and Ln2Co3(L1)12(bipy)2 (Ln = Ho-14, Er-15, Yb-16), were synthesized under hydrothermal conditions and characterized by single crystal X-ray diffraction, IR spectroscopy and magnetic measurements. Structural analyses revealed that 1416 take on a unique linear pentanuclear structural motif. Interestingly, the Ho-containing compound 14 exhibits magnetic relaxation behavior. Full article
(This article belongs to the Special Issue Magnetic Field in Polymer Research)
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12 pages, 4624 KiB  
Article
Polymer-Magnetic Composite Particles of Fe3O4/Poly(o-anisidine) and Their Suspension Characteristics under Applied Magnetic Fields
by Jin Hee Lee, Qi Lu, Jae Yun Lee and Hyoung Jin Choi
Polymers 2019, 11(2), 219; https://doi.org/10.3390/polym11020219 - 28 Jan 2019
Cited by 26 | Viewed by 5100
Abstract
Fe3O4/poly(o-anisidine) (POA) magnetic composite nanoparticles with their core-shell structure were synthesized by chemical oxidation polymerization technique and adopted as a magneto-responsive magnetorheological (MR) material. The chemical structure and morphology of core-shell nanoparticles were identified by FT-IR, SEM, [...] Read more.
Fe3O4/poly(o-anisidine) (POA) magnetic composite nanoparticles with their core-shell structure were synthesized by chemical oxidation polymerization technique and adopted as a magneto-responsive magnetorheological (MR) material. The chemical structure and morphology of core-shell nanoparticles were identified by FT-IR, SEM, TEM, and elemental analyzer. Pycnometer and vibrating sample magnetometer showed that the magnetic saturation and density of the Fe3O4/POA particles were reduced by the POA shell coatings. The rheological properties of the MR suspension dispersed in a silicone oil at various magnetic field strengths were investigated using a rotating rheometer under a magnetic field. The resulting MR suspension showed a typical Newtonian fluid behavior in the absence of external stimuli. When an external magnetic field was applied, it formed a strong chain structure, acting like a solid with a yield stress. Further solid-like behaviors were observed from storage shear relaxation and viscoelastic tests. Finally, the Fe3O4/POA nanoparticles showed better dispersion stability than pure Fe3O4 nanoparticles with 50% improvement. Full article
(This article belongs to the Special Issue Magnetic Field in Polymer Research)
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12 pages, 3257 KiB  
Article
Tetracarbonatodiruthenium Fragments and Lanthanide(III) Ions as Building Blocks to Construct 2D Coordination Polymers
by Daniel Gutiérrez-Martín, Miguel Cortijo, Álvaro Martín-Humanes, Rodrigo González-Prieto, Patricia Delgado-Martínez, Santiago Herrero, José L. Priego and Reyes Jiménez-Aparicio
Polymers 2019, 11(3), 426; https://doi.org/10.3390/polym11030426 - 5 Mar 2019
Cited by 4 | Viewed by 2729
Abstract
Two-dimensional coordination polymers of [Pr(DMSO)2(OH2)3][Ru2(CO3)4(DMSO)(OH2)]·5H2O (Prα) and [Ln(OH2)5][Ru2(CO3)4(DMSO)]·xH2O (Ln = Sm [...] Read more.
Two-dimensional coordination polymers of [Pr(DMSO)2(OH2)3][Ru2(CO3)4(DMSO)(OH2)]·5H2O (Prα) and [Ln(OH2)5][Ru2(CO3)4(DMSO)]·xH2O (Ln = Sm (Smβ), Gd (Gdβ)) formulae have been obtained by reaction of the corresponding Ln(NO3)3·6H2O dissolved in dimethyl sulphoxide (DMSO) and K3[Ru2(CO3)4]·4H2O dissolved in water. Some DMSO molecules are coordinated to the metal atoms reducing the possibilities of connection between the [Ru2(CO3)4]3− and Ln3+ building blocks giving rise to the formation of two-dimensional networks. The size of the Ln3+ ion and the synthetic method seem to have an important influence in the type of two-dimensional structure obtained. Slow diffusion of the reagents gives rise to Prα that forms a 2D net that is built by Ln3+ ions as triconnected nodes and two types of Ru25+ units as bi- and tetraconnected nodes with (2-c)(3-c)2(4-c) stoichiometry (α structure). An analogous synthetic procedure gives Smβ and Gdβ that display a grid-like structure, (2-c)2(4-c)2, formed by biconnected Ln3+ ions and two types of tetraconnected Ru25+ fragments (β structure). The magnetic properties of these compounds are basically explained as the sum of the individual contributions of diruthenium and lanthanide species, although canted ferrimagnetism or weak ferromagnetism are observed at low temperature. Full article
(This article belongs to the Special Issue Magnetic Field in Polymer Research)
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17 pages, 5073 KiB  
Article
Inductive Heating Using a High-Magnetic-Field Pulse to Initiate Chemical Reactions to Generate Composite Materials
by Cordelia Zimmerer, Catalina Salazar Mejia, Toni Utech, Kerstin Arnhold, Andreas Janke and Joachim Wosnitza
Polymers 2019, 11(3), 535; https://doi.org/10.3390/polym11030535 - 21 Mar 2019
Cited by 12 | Viewed by 6774
Abstract
Induction heating is efficient, precise, cost-effective, and clean. The heating process is coupled to an electrically conducting material, usually a metal. As most polymers are dielectric and non-conducting, induction heating is not applicable. In order to transfer energy from an electromagnetic field into [...] Read more.
Induction heating is efficient, precise, cost-effective, and clean. The heating process is coupled to an electrically conducting material, usually a metal. As most polymers are dielectric and non-conducting, induction heating is not applicable. In order to transfer energy from an electromagnetic field into polymer induction structures, conducting materials or materials that absorb the radiation are required. This report gives a brief overview of induction heating processes used in polymer technology. In contrast to metals, most polymer materials are not affected by electromagnetic fields. However, an unwanted temperature rise of the polymer can occur when a radio frequency field is applied. The now available high-field magnetic sources provide a new platform for induction heating at very low frequencies, avoiding unwanted thermal effects within the material. Using polycarbonate and octadecylamine as an example, it is demonstrated that induction heating performed by a magnetic-field pulse with a maximum flux density of 59 T can be used to initiate chemical reactions. A 50 nm thick Ag loop, with a mean diameter of 7 mm, placed in the polymer-polymer interface acts as susceptor and a resistive heating element. The formation of urethane as a linker compound was examined by infrared spectroscopic imaging and differential scanning calorimetry. Full article
(This article belongs to the Special Issue Magnetic Field in Polymer Research)
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14 pages, 5538 KiB  
Article
The Effects of Magnetic Field Alignment on Lithium Ion Transport in a Polymer Electrolyte Membrane with Lamellar Morphology
by Pawel W. Majewski, Manesh Gopinadhan and Chinedum O. Osuji
Polymers 2019, 11(5), 887; https://doi.org/10.3390/polym11050887 - 15 May 2019
Cited by 25 | Viewed by 5166
Abstract
The transport properties of block copolymer-derived polymer electrolyte membranes (PEMs) are sensitive to microstructural disorder originating in the randomly oriented microdomains produced during uncontrolled self-assembly by microphase separation. This microstructural disorder can negatively impact performance due to the presence of conductivity-impeding grain boundaries [...] Read more.
The transport properties of block copolymer-derived polymer electrolyte membranes (PEMs) are sensitive to microstructural disorder originating in the randomly oriented microdomains produced during uncontrolled self-assembly by microphase separation. This microstructural disorder can negatively impact performance due to the presence of conductivity-impeding grain boundaries and the resulting tortuosity of transport pathways. We use magnetic fields to control the orientational order of Li-doped lamellar polyethylene oxide (PEO) microdomains in a liquid crystalline diblock copolymer over large length scales (>3 mm). Microdomain alignment results in an increase in the conductivity of the membrane, but the improvement relative to non-aligned samples is modest, and limited to roughly 50% in the best cases. This limited increase is in stark contrast to the order of magnitude improvement observed for magnetically aligned cylindrical microdomains of PEO. Further, the temperature dependence of the conductivity of lamellar microdomains is seemingly insensitive to the order-disorder phase transition, again in marked contrast to the behavior of cylinder-forming materials. The data are confronted with theoretical predictions of the microstructural model developed by Sax and Ottino. The disparity between the conductivity enhancements obtained by domain alignment of cylindrical and lamellar systems is rationalized in terms of the comparative ease of percolation due to the intersection of randomly oriented lamellar domains (2D sheets) versus the quasi-1D cylindrical domains. These results have important implications for the development of methods to maximize PEM conductivity in electrochemical devices, including batteries. Full article
(This article belongs to the Special Issue Magnetic Field in Polymer Research)
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23 pages, 3678 KiB  
Review
Magnetic Processing of Diamagnetic Materials
by Masafumi Yamato and Tsunehisa Kimura
Polymers 2020, 12(7), 1491; https://doi.org/10.3390/polym12071491 - 3 Jul 2020
Cited by 30 | Viewed by 7355
Abstract
Currently, materials scientists and nuclear magnetic resonance spectroscopists have easy access to high magnetic fields of approximately 10 T supplied by superconducting magnets. Neodymium magnets that generate magnetic fields of approximately 1 T are readily available for laboratory use and are widely used [...] Read more.
Currently, materials scientists and nuclear magnetic resonance spectroscopists have easy access to high magnetic fields of approximately 10 T supplied by superconducting magnets. Neodymium magnets that generate magnetic fields of approximately 1 T are readily available for laboratory use and are widely used in daily life applications, such as mobile phones and electric vehicles. Such common access to magnetic fields—unexpected 30 years ago—has helped researchers discover new magnetic phenomena and use such phenomena to process diamagnetic materials. Although diamagnetism is well known, it is only during the last 30 years that researchers have applied magnetic processing to various classes of diamagnetic materials such as ceramics, biomaterials, and polymers. The magnetic effects that we report herein are largely attributable to the magnetic force, magnetic torque, and magnetic enthalpy that in turn, directly derive from the well-defined magnetic energy. An example of a more complex magnetic effect is orientation of crystalline polymers under an applied magnetic field; researchers do not yet fully understand the crystallization mechanism. Our review largely focuses on polymeric materials. Research topics such as magnetic effect on chiral recognition are interesting yet beyond our scope. Full article
(This article belongs to the Special Issue Magnetic Field in Polymer Research)
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