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Park J, Kim S, Hwang J, Choi JH, So Y, Park S, Ko MJ, Won JC, Suk J, Wu M, Kim YH. Highly Macroporous Polyimide with Chemical Versatility Prepared from Poly(amic acid) Salt-Stabilized High Internal Phase Emulsion Template. ACS Omega 2024; 9:15222-15231. [PMID: 38585077 PMCID: PMC10993319 DOI: 10.1021/acsomega.3c09640] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/02/2023] [Revised: 02/28/2024] [Accepted: 03/06/2024] [Indexed: 04/09/2024]
Abstract
Macroporous polymers have gained significant attention due to their unique mass transport and size-selective properties. In this study, we focused on Polyimide (PI), a high-performance polymer, as an ideal candidate for macroporous structures. Despite various attempts to create macroporous PI (Macro PI) using emulsion templates, challenges remained, including limited chemical diversity and poor control over pore size and porosity. To address these issues, we systematically investigated the role of poly(amic acid) salt (PAAS) polymers as macrosurfactants and matrices. By designing 12 different PAAS polymers with diverse chemical structures, we achieved stable high internal phase emulsions (HIPEs) with >80 vol % internal volume. The resulting Macro PIs exhibited exceptional porosity (>99 vol %) after thermal imidization. We explored the structure-property relationships of these Macro PIs, emphasizing the importance of controlling pore size distribution. Furthermore, our study demonstrated the utility of these Macro PIs as separators in Li-metal batteries, providing stable charging-discharging cycles. Our findings not only enhance the understanding of emulsion-based macroporous polymers but also pave the way for their applications in advanced energy storage systems and beyond.
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Affiliation(s)
- Jongmin Park
- Advanced
Functional Polymers Center, Korea Research
Institute of Chemical Technology (KRICT), Daejeon 34114, Republic of Korea
| | - Sunkyu Kim
- Advanced
Functional Polymers Center, Korea Research
Institute of Chemical Technology (KRICT), Daejeon 34114, Republic of Korea
- Department
of Chemical Engineering, Hanyang University, Seoul 04763, Republic of Korea
| | - Jeonguk Hwang
- Advanced
Functional Polymers Center, Korea Research
Institute of Chemical Technology (KRICT), Daejeon 34114, Republic of Korea
| | - Jun Ha Choi
- Advanced
Functional Polymers Center, Korea Research
Institute of Chemical Technology (KRICT), Daejeon 34114, Republic of Korea
- Department
of Chemical and Biomolecular Engineering, Yonsei University, Seoul 03722, Republic
of Korea
| | - Yujin So
- Advanced
Functional Polymers Center, Korea Research
Institute of Chemical Technology (KRICT), Daejeon 34114, Republic of Korea
| | - Sarang Park
- Advanced
Functional Polymers Center, Korea Research
Institute of Chemical Technology (KRICT), Daejeon 34114, Republic of Korea
| | - Min Jae Ko
- Department
of Chemical Engineering, Hanyang University, Seoul 04763, Republic of Korea
| | - Jong Chan Won
- Advanced
Functional Polymers Center, Korea Research
Institute of Chemical Technology (KRICT), Daejeon 34114, Republic of Korea
- KRICT
School, University of Science and Technology
(UST), Daejeon 34113, Republic of Korea
| | - Jungdon Suk
- KRICT
School, University of Science and Technology
(UST), Daejeon 34113, Republic of Korea
- Advanced
Energy Materials Research Center, Korea
Research Institute of Chemical Technology (KRICT), Daejeon 34114, Republic of Korea
| | - Mihye Wu
- Advanced
Energy Materials Research Center, Korea
Research Institute of Chemical Technology (KRICT), Daejeon 34114, Republic of Korea
| | - Yun Ho Kim
- Advanced
Functional Polymers Center, Korea Research
Institute of Chemical Technology (KRICT), Daejeon 34114, Republic of Korea
- KRICT
School, University of Science and Technology
(UST), Daejeon 34113, Republic of Korea
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Park H, Choi H, Kim J, Yoo S, Mun HJ, Shin TJ, Won JC, Kim HY, Kim YH. Density Functional Theory-Based Approach For Dielectric Constant Estimation of Soluble Polyimide Insulators. J Phys Chem B 2024. [PMID: 38422507 DOI: 10.1021/acs.jpcb.3c07296] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/02/2024]
Abstract
Evaluation of the insulating properties of polymers, such as the dielectric constant and dissipation factor, is crucial in electronic devices, including field-effect transistors and wireless communication applications. This study applies density functional theory (DFT) to predict the dielectric constant of soluble polyimides (SPIs). Various SPIs containing trifluoromethyl groups in the backbone with different pendant types, numbers, and symmetries are successfully synthesized, and their dielectric constants are evaluated and compared with the DFT-estimated values. Two types of DFT-optimized SPIs, single-chain and stacked-chain models, are used to describe the local geometries of the SPIs. In addition, to reveal the relationship between the molecular structure and dielectric constant, further investigations are conducted by considering the dielectric constant of composing ionic and electronic components. The DFT-estimated static dielectric constant of the single-chain model accurately reproduces the corresponding experimental value with at least 80% accuracy. Our approach provides a rational and accelerated strategy to evaluate polymer insulators for electronic devices based on cost-effective DFT calculations.
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Affiliation(s)
- Hyunjin Park
- Chemical Materials Solutions Center, Korea Research Institute of Chemical Technology (KRICT), Daejeon 34114, Republic of Korea
| | - Hyuk Choi
- Department of Materials Science and Engineering, Chungnam National University, Daejeon 34134, Republic of Korea
| | - Jongseok Kim
- Department of Materials Science and Engineering, Chungnam National University, Daejeon 34134, Republic of Korea
| | - Sungmi Yoo
- Chemical Materials Solutions Center, Korea Research Institute of Chemical Technology (KRICT), Daejeon 34114, Republic of Korea
| | - Hyun Jung Mun
- UNIST Central Research Facilities & School of Natural Science, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Republic of Korea
| | - Tae Joo Shin
- UNIST Central Research Facilities & School of Natural Science, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Republic of Korea
| | - Jong Chan Won
- Advanced Functional Polymers Research Center, Korea Research Institute of Chemical Technology (KRICT), Daejeon 34114, Republic of Korea
- KRICT School, University of Science and Technology (UST), Daejeon 34113, Republic of Korea
| | - Hyun You Kim
- Department of Materials Science and Engineering, Chungnam National University, Daejeon 34134, Republic of Korea
| | - Yun Ho Kim
- Advanced Functional Polymers Research Center, Korea Research Institute of Chemical Technology (KRICT), Daejeon 34114, Republic of Korea
- KRICT School, University of Science and Technology (UST), Daejeon 34113, Republic of Korea
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Kim S, Lee Y, Park J, So Y, Jung HT, Ko MJ, Won JC, Jeong S, Kim YH. Green and Facile Synthesis of Hybrid Composites with Ultralow Dielectric Properties from Water-Soluble Polyimide and Dual-Porous Silica Nanoparticles. ACS Appl Mater Interfaces 2023; 15:4408-4418. [PMID: 36520088 DOI: 10.1021/acsami.2c16197] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Here, we proposed an eco-friendly synthetic method for synthesizing hybrid composites with ultralow dielectric properties at high frequencies up to 28 GHz for true 5G communication from aqueous aromatic polyimide (PI) polymers and dual-porous silica nanoparticles (DPS). The "one-step" water-based emulsion template method was used to synthesize the macroporous silica nanoparticles (MPS). A substantially negative ζ potential was produced along the surface of MPS by the poly(vinylpyrrolidone)-based chemical functionalization, enabling excellent aqueous dispersion stability. The water-soluble poly(amic acid) (PAA), as a precursor to PI, was also "one-step" polymerized in an aqueous solution. The MPS were dispersed in a water-soluble PAA matrix to create the hybrid composite films using an entirely water-based approach. The compatibility between the PAA matrix and MPS was elucidated by investigating relatively diverse end-terminated PAAs (with either amine or carboxyl group). It was also discovered that, during a thermally activated imidization reaction, the MPS are in situ converted into the DPS with macro- and microporous structures (with a surface area of 1522.4 m2/g). The thermal, dielectric, mechanical, and morphological characteristics of each composite film were examined, while the amount of DPS in the PI matrix varied from 1 to 20 wt %. With the addition of 5 wt % DPS as an optimum condition, it showed ultralow dielectric properties, with the Dk and Df being 1.615 and 0.003 at a frequency of 28 GHz, respectively, and compatible mechanical properties, with the tensile strength and elastic modulus being 78.2 MPa and 0.32 GPa, respectively. These results can comprehensively satisfy various physical properties required as a substrate material for 5G communication devices.
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Affiliation(s)
- Sunkyu Kim
- Advanced Functional Polymers Center, Korea Research Institute of Chemical Technology, Daejeon 34114, Korea
- Department of Chemical Engineering, Hanyang University, Seoul 04763, Korea
| | - Yeongje Lee
- Department of Advanced Materials Engineering for Information and Electronics, Integrated Education Institute for Frontier Science and Technology (BK21 Four), Kyung Hee University, Yongin-si 17104, Korea
| | - Jongmin Park
- Advanced Functional Polymers Center, Korea Research Institute of Chemical Technology, Daejeon 34114, Korea
| | - Yujin So
- Advanced Functional Polymers Center, Korea Research Institute of Chemical Technology, Daejeon 34114, Korea
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology, Deajeon 34141, Korea
| | - Hee-Tae Jung
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology, Deajeon 34141, Korea
| | - Min Jae Ko
- Department of Chemical Engineering, Hanyang University, Seoul 04763, Korea
| | - Jong Chan Won
- Advanced Functional Polymers Center, Korea Research Institute of Chemical Technology, Daejeon 34114, Korea
- KRICT School, University of Science and Technology, Daejeon 34113, Korea
| | - Sunho Jeong
- Department of Advanced Materials Engineering for Information and Electronics, Integrated Education Institute for Frontier Science and Technology (BK21 Four), Kyung Hee University, Yongin-si 17104, Korea
- Energy Storage Research Center, Korea Institute of Science and Technology, 5, Hwarang-ro 14-gil, Seongbuk-gu, Seoul 02792, Republic of Korea
| | - Yun Ho Kim
- Advanced Functional Polymers Center, Korea Research Institute of Chemical Technology, Daejeon 34114, Korea
- KRICT School, University of Science and Technology, Daejeon 34113, Korea
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Kwon O, Kim M, Choi E, Bae JH, Yoo S, Won JC, Kim YH, Shin JH, Lee JS, Kim DW. High-aspect ratio zeolitic imidazolate framework (ZIF) nanoplates for hydrocarbon separation membranes. Sci Adv 2022; 8:eabl6841. [PMID: 34985959 PMCID: PMC8730619 DOI: 10.1126/sciadv.abl6841] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Metal-organic frameworks with high aspect ratios have the potential to yield high-performance gas separation membranes. We demonstrate the scalable synthesis of high–aspect ratio zeolitic imidazolate framework (ZIF)–8 nanoplates via a direct template conversion method in which high aspect ratio–layered Zn hydroxide sheets [Zn5(NO3)2(OH)8] were used as the sacrificial precursor. Successful phase conversion occurs as a result of the collaboration of low template stability and delayed delivery of 2-methylimidazole in weakly interacting solvents, particularly using acetone. When the ZIF-8 nanoplates with an average aspect ratio of 20 were shear aligned in the 6FDA-DAM polymer matrix by bar coating, the separation performance for propylene/propane far surpassed that of the previously reported mixed matrix and polymeric membranes, showing a propylene permeability of 164 Barrer and selectivity of 33.4 at 40 weight % loadings.
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Affiliation(s)
- Ohchan Kwon
- Department of Chemical and Biomolecular Engineering, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 03722, Republic of Korea
| | - Minsu Kim
- Department of Chemical and Biomolecular Engineering, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 03722, Republic of Korea
| | - Eunji Choi
- Department of Chemical and Biomolecular Engineering, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 03722, Republic of Korea
| | - Jun Hyuk Bae
- Department of Chemical and Biomolecular Engineering, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 03722, Republic of Korea
| | - Sungmi Yoo
- Advanced Materials Division, Korea Research Institute of Chemical Technology, 141 Gajeong-ro, Yuseong-gu, Daejeon 34114, Republic of Korea
| | - Jong Chan Won
- Advanced Materials Division, Korea Research Institute of Chemical Technology, 141 Gajeong-ro, Yuseong-gu, Daejeon 34114, Republic of Korea
- Advanced Materials and Chemical Engineering, KRICT School, University of Science and Technology, 217 Gajeong-ro, Yuseong-gu, Daejeon 34114, Republic of Korea
| | - Yun Ho Kim
- Advanced Materials Division, Korea Research Institute of Chemical Technology, 141 Gajeong-ro, Yuseong-gu, Daejeon 34114, Republic of Korea
- Advanced Materials and Chemical Engineering, KRICT School, University of Science and Technology, 217 Gajeong-ro, Yuseong-gu, Daejeon 34114, Republic of Korea
| | - Ju Ho Shin
- Department of Chemical and Biomolecular Engineering, Sogang University, 35 Baekbeom-ro, Mapo-gu, Seoul 04107, Republic of Korea
| | - Jong Suk Lee
- Department of Chemical and Biomolecular Engineering, Sogang University, 35 Baekbeom-ro, Mapo-gu, Seoul 04107, Republic of Korea
| | - Dae Woo Kim
- Department of Chemical and Biomolecular Engineering, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 03722, Republic of Korea
- Corresponding author.
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So Y, Bae HS, Kang YY, Chung JY, Park NK, Kim J, Jung HT, Won JC, Ryou MH, Kim YH. Eco-Friendly Water-Processable Polyimide Binders with High Adhesion to Silicon Anodes for Lithium-Ion Batteries. Nanomaterials (Basel) 2021; 11:nano11123164. [PMID: 34947515 PMCID: PMC8705944 DOI: 10.3390/nano11123164] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Revised: 11/17/2021] [Accepted: 11/19/2021] [Indexed: 11/16/2022]
Abstract
Silicon is an attractive anode material for lithium-ion batteries (LIBs) because of its natural abundance and excellent theoretical energy density. However, Si-based electrodes are difficult to commercialize because of their significant volume changes during lithiation that can result in mechanical damage. To overcome this limitation, we synthesized an eco-friendly water-soluble polyimide (W-PI) precursor, poly(amic acid) salt (W-PAmAS), as a binder for Si anodes via a simple one-step process using water as a solvent. Using the W-PAmAS binder, a composite Si electrode was achieved by low-temperature processing at 150 °C. The adhesion between the electrode components was further enhanced by introducing 3,5-diaminobenzoic acid, which contains free carboxylic acid (-COOH) groups in the W-PAmAS backbone. The -COOH of the W-PI binder chemically interacts with the surface of Si nanoparticles (SiNPs) by forming ester bonds, which efficiently bond the SiNPs, even during severe volume changes. The Si anode with W-PI binder showed improved electrochemical performance with a high capacity of 2061 mAh g-1 and excellent cyclability of 1883 mAh g-1 after 200 cycles at 1200 mA g-1. Therefore, W-PI can be used as a highly effective polymeric binder in Si-based high-capacity LIBs.
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Affiliation(s)
- Yujin So
- Advanced Materials Division, Korea Research Institute of Chemical Technology (KRICT), Daejeon 34114, Korea; (Y.S.); (Y.Y.K.); (J.Y.C.); (N.K.P.); (J.K.)
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Korea;
| | - Hyeon-Su Bae
- Department of Chemical and Biological Engineering, Hanbat National University, Daejeon 34158, Korea;
| | - Yi Young Kang
- Advanced Materials Division, Korea Research Institute of Chemical Technology (KRICT), Daejeon 34114, Korea; (Y.S.); (Y.Y.K.); (J.Y.C.); (N.K.P.); (J.K.)
| | - Ji Yun Chung
- Advanced Materials Division, Korea Research Institute of Chemical Technology (KRICT), Daejeon 34114, Korea; (Y.S.); (Y.Y.K.); (J.Y.C.); (N.K.P.); (J.K.)
- Korea Research Institute of Chemical Technology (KRICT) School, University of Science and Technology, Daejeon 34113, Korea
| | - No Kyun Park
- Advanced Materials Division, Korea Research Institute of Chemical Technology (KRICT), Daejeon 34114, Korea; (Y.S.); (Y.Y.K.); (J.Y.C.); (N.K.P.); (J.K.)
| | - Jinsoo Kim
- Advanced Materials Division, Korea Research Institute of Chemical Technology (KRICT), Daejeon 34114, Korea; (Y.S.); (Y.Y.K.); (J.Y.C.); (N.K.P.); (J.K.)
| | - Hee-Tae Jung
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Korea;
| | - Jong Chan Won
- Advanced Materials Division, Korea Research Institute of Chemical Technology (KRICT), Daejeon 34114, Korea; (Y.S.); (Y.Y.K.); (J.Y.C.); (N.K.P.); (J.K.)
- Korea Research Institute of Chemical Technology (KRICT) School, University of Science and Technology, Daejeon 34113, Korea
- Correspondence: (J.C.W.); (M.-H.R.); (Y.H.K.); Tel.: +82-860-7294 (J.C.W.); +82-42-821-1534 (M.-H.R.); +82-42-860-7274 (Y.H.K.)
| | - Myung-Hyun Ryou
- Department of Chemical and Biological Engineering, Hanbat National University, Daejeon 34158, Korea;
- Correspondence: (J.C.W.); (M.-H.R.); (Y.H.K.); Tel.: +82-860-7294 (J.C.W.); +82-42-821-1534 (M.-H.R.); +82-42-860-7274 (Y.H.K.)
| | - Yun Ho Kim
- Advanced Materials Division, Korea Research Institute of Chemical Technology (KRICT), Daejeon 34114, Korea; (Y.S.); (Y.Y.K.); (J.Y.C.); (N.K.P.); (J.K.)
- Korea Research Institute of Chemical Technology (KRICT) School, University of Science and Technology, Daejeon 34113, Korea
- Correspondence: (J.C.W.); (M.-H.R.); (Y.H.K.); Tel.: +82-860-7294 (J.C.W.); +82-42-821-1534 (M.-H.R.); +82-42-860-7274 (Y.H.K.)
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Park H, Yoo S, Ha J, Kim J, Mun HJ, Shin TJ, Won JC, Kim YH. Tailored Polymer Gate Dielectric Engineering to Optimize Flexible Organic Field-Effect Transistors and Complementary Integrated Circuits. ACS Appl Mater Interfaces 2021; 13:30921-30929. [PMID: 34121383 DOI: 10.1021/acsami.1c06293] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The increasing demand for solution-processed and flexible organic electronics has promoted the fabrication of integrated logic circuits using organic field-effect transistors (OFETs) instead of fundamental unit devices. This has been made possible through the rapid development of materials and processes in the past few decades. It is important for the p- and n-type OFETs using different organic semiconductors (OSCs) to have complementarily matched electrical characteristics, which significantly improve the performance of organic logic circuits. In this study, an efficient strategy to optimize the performance of flexible organic electronics, such as OFETs and complementary inverters, is proposed using a combination of polymer insulators tailored to each OSC type. Photopatternable soluble copolyimides (ScoPIs), which exhibit excellent insulating properties and chemical resistance, are synthesized and applied as gate dielectric layers in the OFETs. The material and electrical properties are systematically investigated by varying the molecular ratio of ScoPIs to determine the optimal conditions for each OFET type. As a result, complementary inverters report 1.67 times higher integration density compared to the conventional ones while maintaining gain, switching threshold, and static noise margin of 23.7 V/V, 22.1 V, and 12.1 V, respectively, at a supply voltage of 40 V. The flexible complementary inverters are successfully demonstrated by fully exploiting the advantages of ScoPIs.
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Affiliation(s)
- Hyunjin Park
- Chemical Materials Solutions Center, Korea Research Institute of Chemical Technology (KRICT), Daejeon 34114, Republic of Korea
| | - Sungmi Yoo
- Advanced Functional Polymers Center, KRICT, Daejeon 34114, Republic of Korea
| | - Jinha Ha
- Advanced Functional Polymers Center, KRICT, Daejeon 34114, Republic of Korea
- KRICT School, University of Science and Technology (UST), Daejeon 34113, Republic of Korea
| | - Jinsoo Kim
- Advanced Functional Polymers Center, KRICT, Daejeon 34114, Republic of Korea
| | - Hyun Jung Mun
- UNIST Central Research Facilities & School of Natural Science, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Republic of Korea
| | - Tae Joo Shin
- UNIST Central Research Facilities & School of Natural Science, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Republic of Korea
| | - Jong Chan Won
- Advanced Functional Polymers Center, KRICT, Daejeon 34114, Republic of Korea
- KRICT School, University of Science and Technology (UST), Daejeon 34113, Republic of Korea
| | - Yun Ho Kim
- Advanced Functional Polymers Center, KRICT, Daejeon 34114, Republic of Korea
- KRICT School, University of Science and Technology (UST), Daejeon 34113, Republic of Korea
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Bae JH, Won JC, Lim WB, Kim BJ, Lee JH, Min JG, Seo MJ, Mo YH, Huh P. Tacky-Free Polyurethanes Pressure-Sensitive Adhesives by Molecular-Weight and HDI Trimer Design. Materials (Basel) 2021; 14:2164. [PMID: 33922818 PMCID: PMC8123004 DOI: 10.3390/ma14092164] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Revised: 04/20/2021] [Accepted: 04/21/2021] [Indexed: 11/17/2022]
Abstract
Polyurethane pressure-sensitive adhesives (PU-PSAs) with satisfactory tack, cohesion, and removability were newly developed through the synthetic process by reacting methylene diisocyanate, poly(ethylene glycol) (PEG), and a 1,4-butanediol chain extender based on the different HDI/HDI trimer ratios. The sticking properties of PU-PSAs depended on both the HDI/HDI trimer ratio and crosslinking-agent composition in the formulation. The molecular weight (MW) dependence of adhesion in PU-PSA was observed in the range of 1000 < Mn < 3000, suggesting that the increase in MW limits the pressure-sensitive adhesion of these samples. The differences in the crosslinking-density significantly affected the cohesion, adhesion, and tack in PU-PSA. The formulation of 50 wt.% 600PEG and 50 wt.% crosslinking-agent and an HDI/HDI trimer ratio of 1.0 led to the optimal balance between the adhesion and cohesion properties owing to the sufficient tack, high 180-peel strength, and good cohesion.
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Affiliation(s)
| | | | | | | | | | | | | | | | - PilHo Huh
- Department of Polymer Science and Engineering, Pusan National University, Busan 609-735, Korea; (J.-H.B.); (J.C.W.); (W.B.L.); (B.J.K.); (J.H.L.); (J.G.M.); (M.J.S.); (Y.H.M.)
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Bae JH, Won JC, Lim WB, Lee JH, Min JG, Kim SW, Kim JH, Huh P. Highly Flexible and Photo-Activating Acryl-Polyurethane for 3D Steric Architectures. Polymers (Basel) 2021; 13:polym13060844. [PMID: 33801858 PMCID: PMC7999262 DOI: 10.3390/polym13060844] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Revised: 03/04/2021] [Accepted: 03/08/2021] [Indexed: 12/15/2022] Open
Abstract
An acryl-functionalized polyurethane (PU) series was successfully synthesized using poly(tetramethylene ether) glycol-methylene diphenyl diisocyanate (PTMG-MDI) oligomer based on urethane methacrylates to control the flexibility of photo-cured 3D printing architectures. The mass ratio of acryl-urethane prepolymer: 1,4-butanediol (BD) chain-extender: diphenyl(2,4,6-trimethylbenzoyl) phosphine oxide (TPO) photoinitiator was 10:0.25:1. To produce suitably hard and precisely curved 3D architectures, the optimal UV absorbance and exposure energy of the acryl-PTMG-MDI resin were controlled precisely. Owing to the optimized viscosity of the acryl-PTMG-MDI resins, they could be printed readily by digital light processing (DLP) to form precisely curved 3D architectures after mixing with 1,6-hexanediol diacrylate (HDDA). The acryl-PTMG-MDI formulations showed much better flexural resolution than the neat resins. The printed 3D structure exhibited high surface hardness, good mechanical strength, and high elasticity for flexible applications in consumer/industrial and biomedical fields.
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Affiliation(s)
| | | | | | | | | | | | | | - PilHo Huh
- Correspondence: ; Tel.: +82-51-510-3637
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Bae JH, Won JC, Lim WB, Min JG, Lee JH, Kwon CR, Lee GH, Huh P. Synthesis and Characteristics of Eco-Friendly 3D Printing Material Based on Waterborne Polyurethane. Polymers (Basel) 2020; 13:polym13010044. [PMID: 33374360 PMCID: PMC7794856 DOI: 10.3390/polym13010044] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 12/17/2020] [Accepted: 12/23/2020] [Indexed: 11/23/2022] Open
Abstract
Photo-cured 3D architectures are successfully printed using the designed waterborne polyurethane-acrylate (WPUA) formulation. A WPUA series is synthesized in the presence of polycaprolactone diol (PCL) and 4,4′-methylene dicyclohexyl diisocyanate (H12MDI) as the soft segment part, dimethylolbutanoic acid (DMBA) as the emulsifier, and triethylamine (TEA) as the neutralizer, as a function of prepolymer molecular weight. The compatibility of WPUA and the photo-activating acryl monomer is as a key factor to guarantee the high resolution of 3D digital light processing (DLP) printing. The optimized blending formulations are tuned by using triacrylate monomers instead of diacrylate derivatives. For the high-accuracy and fine features of 3D DLP printing, WPUA are designed to be a suitable molecular structure for a 385 nm wavelength source, and the target viscosity is achieved in the range from 150 to 250 Cp. Photo-cured 3D architectures based on WPUA exhibit good flexural strength and high resolution.
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Affiliation(s)
| | | | | | | | | | | | | | - Pilho Huh
- Correspondence: ; Tel.: +82-51-510-3637
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Choi J, Yang K, Bae HS, Phiri I, Ahn HJ, Won JC, Lee YM, Kim YH, Ryou MH. Highly Stable Porous Polyimide Sponge as a Separator for Lithium-metal Secondary Batteries. Nanomaterials (Basel) 2020; 10:nano10101976. [PMID: 33036223 PMCID: PMC7600698 DOI: 10.3390/nano10101976] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Revised: 09/26/2020] [Accepted: 09/30/2020] [Indexed: 11/16/2022]
Abstract
To inhibit Li-dendrite growth on lithium (Li)-metal electrodes, which causes capacity deterioration and safety issues in Li-ion batteries, we prepared a porous polyimide (PI) sponge using a solution-processable high internal-phase emulsion technique with a water-soluble PI precursor solution; the process is not only simple but also environmentally friendly. The prepared PI sponge was processed into porous PI separators and used for Li-metal electrodes. The physical properties (e.g., thermal stability, liquid electrolyte uptake, and ionic conductivity) of the porous PI separators and their effect on the Li-metal anodes (e.g., self-discharge and open-circuit voltage properties after storage, cycle performance, rate capability, and morphological changes) were investigated. Owing to the thermally stable properties of the PI polymer, the porous PI separators demonstrated no dimensional changes up to 180 °C. In comparison with commercialized polyethylene (PE) separators, the porous PI separators exhibited improved wetting ability for liquid electrolytes; thus, the latter improved not only the physical properties (e.g., improved the electrolyte uptake and ionic conductivity) but also the electrochemical properties of Li-metal electrodes (e.g., maintained stable self-discharge capacity and open-circuit voltage features after storage and improved the cycle performance and rate capability) in comparison with PE separators.
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Affiliation(s)
- Junyoung Choi
- Department of Chemical and Biological Engineering, Hanbat National University, 125 Dongseo-daero, Yuseong-gu, Daejeon 34158, Korea; (J.C.); (H.-S.B.); (I.P.)
- Advanced Materials Division, Korea Research Institute of Chemical Technology (KRICT), 141 Gajeongro, Yuseong-gu, Daejeon 34114, Korea; (K.Y.); (H.J.A.); (J.C.W.)
- Korea Research Institute of Chemical Technology (KRICT) School, University of Science and Technology, 217 Gajeongro, Yuseong-gu, Daejeon 34113, Korea
| | - Kwansoo Yang
- Advanced Materials Division, Korea Research Institute of Chemical Technology (KRICT), 141 Gajeongro, Yuseong-gu, Daejeon 34114, Korea; (K.Y.); (H.J.A.); (J.C.W.)
- Korea Research Institute of Chemical Technology (KRICT) School, University of Science and Technology, 217 Gajeongro, Yuseong-gu, Daejeon 34113, Korea
| | - Hyeon-Su Bae
- Department of Chemical and Biological Engineering, Hanbat National University, 125 Dongseo-daero, Yuseong-gu, Daejeon 34158, Korea; (J.C.); (H.-S.B.); (I.P.)
| | - Isheunesu Phiri
- Department of Chemical and Biological Engineering, Hanbat National University, 125 Dongseo-daero, Yuseong-gu, Daejeon 34158, Korea; (J.C.); (H.-S.B.); (I.P.)
| | - Hyun Jeong Ahn
- Advanced Materials Division, Korea Research Institute of Chemical Technology (KRICT), 141 Gajeongro, Yuseong-gu, Daejeon 34114, Korea; (K.Y.); (H.J.A.); (J.C.W.)
- Korea Research Institute of Chemical Technology (KRICT) School, University of Science and Technology, 217 Gajeongro, Yuseong-gu, Daejeon 34113, Korea
| | - Jong Chan Won
- Advanced Materials Division, Korea Research Institute of Chemical Technology (KRICT), 141 Gajeongro, Yuseong-gu, Daejeon 34114, Korea; (K.Y.); (H.J.A.); (J.C.W.)
- Korea Research Institute of Chemical Technology (KRICT) School, University of Science and Technology, 217 Gajeongro, Yuseong-gu, Daejeon 34113, Korea
| | - Yong Min Lee
- Department of Energy Science and Engineering, Daegu Gyeongbuk Institute of Science and Technology (DGIST), 333 Techno Jungang-Daero, Daegu 42988, Korea
- Correspondence: (Y.M.L.); (Y.H.K.); (M.-H.R.); Tel.: +82-42-785-6425 (Y.M.L); +82-42-860-7274 (Y.H.K.); +82-42-821-1534 (M.-H.R.)
| | - Yun Ho Kim
- Advanced Materials Division, Korea Research Institute of Chemical Technology (KRICT), 141 Gajeongro, Yuseong-gu, Daejeon 34114, Korea; (K.Y.); (H.J.A.); (J.C.W.)
- Korea Research Institute of Chemical Technology (KRICT) School, University of Science and Technology, 217 Gajeongro, Yuseong-gu, Daejeon 34113, Korea
- Correspondence: (Y.M.L.); (Y.H.K.); (M.-H.R.); Tel.: +82-42-785-6425 (Y.M.L); +82-42-860-7274 (Y.H.K.); +82-42-821-1534 (M.-H.R.)
| | - Myung-Hyun Ryou
- Department of Chemical and Biological Engineering, Hanbat National University, 125 Dongseo-daero, Yuseong-gu, Daejeon 34158, Korea; (J.C.); (H.-S.B.); (I.P.)
- Correspondence: (Y.M.L.); (Y.H.K.); (M.-H.R.); Tel.: +82-42-785-6425 (Y.M.L); +82-42-860-7274 (Y.H.K.); +82-42-821-1534 (M.-H.R.)
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Yang K, Kang YY, Ahn HJ, Kim DG, Park NK, Choi SQ, Won JC, Kim YH. Porous boron nitride/polyimide composite films with high thermal diffusivity and low dielectric properties via high internal phase Pickering emulsion method. J IND ENG CHEM 2020. [DOI: 10.1016/j.jiec.2019.10.010] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Park H, Yoo S, Ahn H, Bang J, Jeong Y, Yi M, Won JC, Jung S, Kim YH. Low-Temperature Solution-Processed Soluble Polyimide Gate Dielectrics: From Molecular-Level Design to Electrically Stable and Flexible Organic Transistors. ACS Appl Mater Interfaces 2019; 11:45949-45958. [PMID: 31738047 DOI: 10.1021/acsami.9b14041] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Aromatic soluble polyimides (PIs) have been widely used in organic field-effect transistors (OFETs) as gate dielectric layers due to their promising features such as outstanding chemical resistance, thermal stability, low-temperature processability, and mechanical flexibility. However, the molecular structures of soluble PIs on the electrical characteristics of OFETs are not yet fully understood. In this work, the material, dielectric, and electrical properties are evaluated to systematically investigate the chemical structure effect of aromatic dianhydride and diamine monomers on the device performance. Four soluble PIs based on 4,4'-(Hexafluoroisopropylidene)diphthalic anhydride (6FDA) and 5-(2,5-Dioxotetrahydrofuryl)-3-methyl-3-cyclohexene-1,2-dicarboxylic anhydride, in which the monomeric precursors contain different backbones, side groups, and linkages, were employed to compare the chemical structure impact. The dielectric properties, which significantly affect the charge transport and crystallinity of OSC thin films, clearly depended on the soluble PI types as well as the surface energy and the thermal stability. Furthermore, the electrical characteristic measurement and parameter extraction of OFETs based on TIPS-pentacene revealed that the 6FDA-based soluble PIs, which lead to high field-effect mobility, near-zero threshold electric field, and outstanding electrical stability under bias stress, are the most promising gate dielectric candidates. Finally, low-temperature solution-processed OFETs are successfully integrated with ultrathin flexible substrates, and they exhibit no significant electrical performance loss after mechanical flexibility tests. This work presents a step forward in the development of soluble PI gate dielectrics for flexible electronic devices with high device performance.
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Affiliation(s)
- Hyunjin Park
- Advanced Materials Division , Korea Research Institute of Chemical Technology (KRICT) , Daejeon 34114 , Republic of Korea
| | - Sungmi Yoo
- Advanced Materials Division , Korea Research Institute of Chemical Technology (KRICT) , Daejeon 34114 , Republic of Korea
| | - Hyungju Ahn
- Pohang Accelerator Laboratory , Gyeongbuk 37673 , Republic of Korea
| | - Joohee Bang
- Pohang Accelerator Laboratory , Gyeongbuk 37673 , Republic of Korea
| | - Yuri Jeong
- Advanced Materials Division , Korea Research Institute of Chemical Technology (KRICT) , Daejeon 34114 , Republic of Korea
| | - Mihye Yi
- Advanced Materials Division , Korea Research Institute of Chemical Technology (KRICT) , Daejeon 34114 , Republic of Korea
| | - Jong Chan Won
- Advanced Materials Division , Korea Research Institute of Chemical Technology (KRICT) , Daejeon 34114 , Republic of Korea
- Chemical Convergence Materials and Processes, KRICT School , University of Science and Technology (UST) , Daejeon 34113 , Republic of Korea
| | - Sungjune Jung
- Department of Creative IT Engineering , Pohang University of Science and Technology (POSTECH) , Gyeongbuk 37673 , Republic of Korea
| | - Yun Ho Kim
- Advanced Materials Division , Korea Research Institute of Chemical Technology (KRICT) , Daejeon 34114 , Republic of Korea
- Chemical Convergence Materials and Processes, KRICT School , University of Science and Technology (UST) , Daejeon 34113 , Republic of Korea
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Yoo S, Kim DG, Ha T, Chan Won J, Jang KS, Kim YH. Solution-Processable, Thin, and High-κ Dielectric Polyurea Gate Insulator with Strong Hydrogen Bonding for Low-Voltage Organic Thin-Film Transistors. ACS Appl Mater Interfaces 2018; 10:32462-32470. [PMID: 30175586 DOI: 10.1021/acsami.8b11083] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
We developed a solution-processable, thin, and high-dielectric polyurea-based organic gate insulator for low-voltage operation and high performance of organic thin-film transistors (OTFTs). A 60 nm-thick polyurea thin film exhibited a high dielectric constant of 5.82 and excellent electrical insulating properties owing to strong hydrogen bonding. The hydrogen bonding of the synthesized polyurea was confirmed using infrared spectroscopy and was quantitatively evaluated by measuring the interactive force using atomic force microscopy. Moreover, the effect of hydrogen bonding of polyurea on the insulating properties was systematically investigated through the combination of various monomers and control of the thickness of the polyurea film. The dinaphtho[2,3- b:2',3'- f]thieno[3,2- b]thiophene-based OTFTs with the polyurea gate insulator showed excellent thin-film transistor (TFT) performance with a field-effect mobility of 1.390 cm2/V·s and an on/off ratio of ∼105 at a low operation voltage below 2 V. In addition, it is possible to fabricate flexible polymer organic semiconductor (OSC)-based TFT devices using a solution process, owing to excellent solvent stability in various organic solvents. We believe that the solution-processable polyurea gate insulator with a high dielectric constant and good insulation properties is a promising candidate for low-voltage-operated OTFTs using various OSCs.
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Affiliation(s)
- Sungmi Yoo
- Advanced Materials Division , Korea Research Institute of Chemical Technology , Daejeon 34114 , Republic of Korea
| | - Dong-Gyun Kim
- Advanced Materials Division , Korea Research Institute of Chemical Technology , Daejeon 34114 , Republic of Korea
- Chemical Convergence Materials and Processes , KRICT School, University of Science and Technology , Daejeon 34113 , Republic of Korea
| | - Taewook Ha
- Advanced Materials Division , Korea Research Institute of Chemical Technology , Daejeon 34114 , Republic of Korea
- Department of Chemistry , Korea University , Seoul 02841 , Republic of Korea
| | - Jong Chan Won
- Advanced Materials Division , Korea Research Institute of Chemical Technology , Daejeon 34114 , Republic of Korea
- Chemical Convergence Materials and Processes , KRICT School, University of Science and Technology , Daejeon 34113 , Republic of Korea
| | - Kwang-Suk Jang
- Department of Chemical and Molecular Engineering , Hanyang University , Ansan 15588 , Republic of Korea
| | - Yun Ho Kim
- Advanced Materials Division , Korea Research Institute of Chemical Technology , Daejeon 34114 , Republic of Korea
- Chemical Convergence Materials and Processes , KRICT School, University of Science and Technology , Daejeon 34113 , Republic of Korea
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Chae B, Hong DG, Jung YM, Won JC, Lee SW. Investigation of phase separated polyimide blend films containing boron nitride using FTIR imaging. Spectrochim Acta A Mol Biomol Spectrosc 2018; 195:1-6. [PMID: 29353111 DOI: 10.1016/j.saa.2018.01.025] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2017] [Revised: 01/02/2018] [Accepted: 01/10/2018] [Indexed: 06/07/2023]
Abstract
Immiscible aromatic polyimide (PI) blend films and a PI blend film incorporated with thermally conductive boron nitride (BN) were prepared, and their phase separation behaviors were examined by optical microscopy and FTIR imaging. The 2,2'-bis(trifluoromethyl)benzidine (TFMB)-containing and 4,4'-thiodianiline (TDA)-containing aromatic PI blend films and a PI blend/BN composite film show two clearly separated regions; one region is the TFMB-rich phase, and the other region is the TDA-rich phase. The introduction of BN induces morphological changes in the immiscible aromatic PI blend film without altering the composition of either domain. In particular, the BN is selectively incorporated into the TDA-rich phase in this study.
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Affiliation(s)
- Boknam Chae
- Pohang Accelerator Laboratory, Pohang 37673, Republic of Korea
| | - Deok Gi Hong
- School of Chemical Engineering, Yeungnam University, Gyeongsan 38541, Republic of Korea
| | - Young Mee Jung
- Department of Chemistry, Kangwon National University, Chunchon 24341, Republic of Korea.
| | - Jong Chan Won
- Center for Advanced Functional Polymers, Korea Research Institute of Chemical Technology, Daejeon 34114, Republic of Korea.
| | - Seung Woo Lee
- School of Chemical Engineering, Yeungnam University, Gyeongsan 38541, Republic of Korea.
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15
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Lee JM, Park EY, Kim KM, Won JC, Jung TK, Lee SK. Comparison of activated clotting times measured using the Hemochron Jr. Signature and Medtronic ACT Plus during cardiopulmonary bypass with acute normovolemic haemodilution. J Int Med Res 2017; 46:873-882. [PMID: 28974132 PMCID: PMC5971518 DOI: 10.1177/0300060517731952] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Objective This study compared the activated clotting time (ACT) measured using the Hemochron Jr. Signature (HACT) with the ACT measured using the Medtronic ACT Plus (MACT) during cardiopulmonary bypass (CPB) with acute normovolemic haemodilution (ANH) in patients undergoing cardiac surgery. Methods The ACT was checked at baseline with both devices after inducing anaesthesia, and 400 to 800 mL of whole blood was withdrawn to induce moderate ANH. Before initiating CPB, a 300-IU/kg bolus dose of heparin was administered to maintain the HACT at >400 s; protamine was later given to reverse the anticoagulation. The ACT was checked using both devices at baseline, during heparinisation, and after protamine administration. Results In total, 106 pairs of samples from 29 patients were analysed. The ACT showed a good correlation between the two devices (r = 0.956). However, Bland–Altman analysis showed that the MACT was higher, particularly at baseline and during heparinisation. Multiple regression analysis showed that the blood glucose concentration significantly influenced the differences between the two ACT devices. Conclusions The HACT was lower than the MACT during CPB with ANH in patients undergoing cardiac surgery. Clinicians should be cautious when using each ACT device within generally accepted reference ACT values.
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Affiliation(s)
- Jung Min Lee
- 1 Department of Anaesthesiology and Pain Medicine, Hallym University Sacred Heart Hospital, College of Medicine, Hallym University, Anyang, Republic of Korea
| | - Eun Young Park
- 1 Department of Anaesthesiology and Pain Medicine, Hallym University Sacred Heart Hospital, College of Medicine, Hallym University, Anyang, Republic of Korea
| | - Kyung Mi Kim
- 1 Department of Anaesthesiology and Pain Medicine, Hallym University Sacred Heart Hospital, College of Medicine, Hallym University, Anyang, Republic of Korea
| | - Jong Chan Won
- 1 Department of Anaesthesiology and Pain Medicine, Hallym University Sacred Heart Hospital, College of Medicine, Hallym University, Anyang, Republic of Korea
| | - Tack Koon Jung
- 2 Department of Cardiovascular Surgery, 37129 Bundang CHA Medical Center , CHA Bundang Medical Center, CHA University, Seongnam, Republic of Korea
| | - Soo Kyung Lee
- 1 Department of Anaesthesiology and Pain Medicine, Hallym University Sacred Heart Hospital, College of Medicine, Hallym University, Anyang, Republic of Korea
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Park JY, Park JH, Park YM, Park NK, Kim YH, Won JC. Synthesis and Characterization of Polyimide with Improved Adhesion Property for Copper Foil. pk 2017. [DOI: 10.7317/pk.2017.41.5.882] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Yoon HW, Bok C, Park NK, Jung HM, Kim YS, Kim BG, Suh DH, Won JC, Kim YH. Enhanced dielectric properties of polyimide/BaTiO3 nanocomposite by embedding the polypyrrole@polyimide core-shell nanoparticles. Macromol Res 2017. [DOI: 10.1007/s13233-017-5039-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Kim DG, Kim YH, Shin TJ, Cha EJ, Kim DS, Kim BG, Yoo Y, Kim YS, Yi MH, Won JC. Highly anisotropic thermal conductivity of discotic nematic liquid crystalline films with homeotropic alignment. Chem Commun (Camb) 2017; 53:8227-8230. [DOI: 10.1039/c7cc02891a] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Homeotropic alignment and photo-crosslinking of discotic nematic liquid crystals yield free-standing films with high in-plane thermal conductivity and thermal conductivity anisotropy.
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19
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Kim S, Ha T, Yoo S, Ka JW, Kim J, Won JC, Choi DH, Jang KS, Kim YH. Metal-oxide assisted surface treatment of polyimide gate insulators for high-performance organic thin-film transistors. Phys Chem Chem Phys 2017; 19:15521-15529. [DOI: 10.1039/c7cp01535f] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
We developed a facile method for treating polyimide-based organic gate insulator (OGI) surfaces with self-assembled monolayers (SAMs) by introducing metal-oxide interlayers, called the metal-oxide assisted SAM treatment (MAST).
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Affiliation(s)
- Sohee Kim
- Division of Advanced Materials
- Korea Research Institute of Chemical Technology
- Daejeon 34114
- Republic of Korea
| | - Taewook Ha
- Division of Advanced Materials
- Korea Research Institute of Chemical Technology
- Daejeon 34114
- Republic of Korea
- Department of Chemistry
| | - Sungmi Yoo
- Division of Advanced Materials
- Korea Research Institute of Chemical Technology
- Daejeon 34114
- Republic of Korea
| | - Jae-Won Ka
- Division of Advanced Materials
- Korea Research Institute of Chemical Technology
- Daejeon 34114
- Republic of Korea
| | - Jinsoo Kim
- Division of Advanced Materials
- Korea Research Institute of Chemical Technology
- Daejeon 34114
- Republic of Korea
- KRICT School
| | - Jong Chan Won
- Division of Advanced Materials
- Korea Research Institute of Chemical Technology
- Daejeon 34114
- Republic of Korea
- KRICT School
| | - Dong Hoon Choi
- Department of Chemistry
- Korea University
- Seoul 02841
- Republic of Korea
| | - Kwang-Suk Jang
- Department of Chemical Engineering and Research Center of Chemical Technology
- Hankyong National University
- Anseong 17579
- Republic of Korea
| | - Yun Ho Kim
- Division of Advanced Materials
- Korea Research Institute of Chemical Technology
- Daejeon 34114
- Republic of Korea
- KRICT School
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Kim YJ, Kim JH, Won JC. Studies of Thermal Imidization Kinetics of Polyisoimide Based upon 4,4′-[1,4-Phenylenebis-(1-methyl ethylidene)] Bisaniline and 4,4′-Oxydiphthalic Anhydride in Solid State. HIGH PERFORM POLYM 2016. [DOI: 10.1177/0954008305041946] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The curing kinetics of the polyisoimide (BIS-P/ODPA), based upon 4,4′-[1,4-phenylene-bis-(1- methyl ethylidene)] bisaniline (Bis-P) and 4,4′-oxydiphthalic anhydride (ODPA), was studied by differential scanning calorimetry (DSC). The glass transition temperatures of the partially imidized polyisoimides (Bis-P/ODPA) were measured by DSC as a function of fractional conversion. The thermal imidization of polyisoimides in the solid state showed a maximum degree of imidization that can be achieved at a given isothermal temperature probably due to the diffusion-controlled reaction characteristics near vitrification ( T g effect). Dynamic curing studies were performed at different heating rates of 1, 2, 5, 10, 15, 20, 25, 30°1. These data were analyzed for obtaining the activation energy and pre-exponetial value for the imidization reaction. The thermal imidization was well described by first-order kinetics with activation energy of 181-202 kJ mol−1 and the pre-exponential factor of 36-40 min−1.
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Affiliation(s)
- Young Jun Kim
- School of Applied Chemistry and Chemical Engineering, Sung Kyun Kwan University, Jangan-Ku, Suwon, Kyunggi-do, Korea,
| | - Ji-Heung Kim
- School of Applied Chemistry and Chemical Engineering, Sung Kyun Kwan University, Jangan-Ku, Suwon, Kyunggi-do, Korea
| | - Jong Chan Won
- Advanced Material Division, Korea Research Institute of Chemical Technology, Yusung, Taejon, Korea
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Lee K, Jeon JW, Maeng BM, Huh KM, Chan Won J, Yoo Y, Kim YS, Kim BG. Synthesis and characterization of polyethersulfone with intrinsic microporosity. RSC Adv 2016. [DOI: 10.1039/c6ra13034h] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
A new non-ladder-type polyethersulfone-type PIM that incorporated a linear sulfone moiety was synthesized.
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Affiliation(s)
- Kyuchul Lee
- Advanced Material Division
- Korea Research Institute of Chemical Technology
- Daejeon
- Republic of Korea
- Department of Nanomaterials Science and Engineering
| | - Jun Woo Jeon
- Advanced Material Division
- Korea Research Institute of Chemical Technology
- Daejeon
- Republic of Korea
- Department of Nanomaterials Science and Engineering
| | - Bo Mi Maeng
- Advanced Material Division
- Korea Research Institute of Chemical Technology
- Daejeon
- Republic of Korea
- Department of Polymers Science and Engineering
| | - Kang Moo Huh
- Department of Polymers Science and Engineering
- Chungnam National University
- Daejeon
- Republic of Korea
| | - Jong Chan Won
- Advanced Material Division
- Korea Research Institute of Chemical Technology
- Daejeon
- Republic of Korea
- Department of Nanomaterials Science and Engineering
| | - Youngjae Yoo
- Advanced Material Division
- Korea Research Institute of Chemical Technology
- Daejeon
- Republic of Korea
- Department of Nanomaterials Science and Engineering
| | - Yong Seok Kim
- Advanced Material Division
- Korea Research Institute of Chemical Technology
- Daejeon
- Republic of Korea
- Department of Nanomaterials Science and Engineering
| | - Byoung Gak Kim
- Advanced Material Division
- Korea Research Institute of Chemical Technology
- Daejeon
- Republic of Korea
- Department of Nanomaterials Science and Engineering
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Lee SS, Kim SK, Won JC, Kim YH, Kim SH. Back Cover: Reconfigurable Photonic Capsules Containing Cholesteric Liquid Crystals with Planar Alignment (Angew. Chem. Int. Ed. 50/2015). Angew Chem Int Ed Engl 2015. [DOI: 10.1002/anie.201509872] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Ha SM, Kwon OH, Oh YG, Kim YS, Lee SG, Won JC, Cho KS, Kim BG, Yoo Y. Thermally conductive polyamide 6/carbon filler composites based on a hybrid filler system. Sci Technol Adv Mater 2015; 16:065001. [PMID: 27877843 PMCID: PMC5069987 DOI: 10.1088/1468-6996/16/6/065001] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/19/2015] [Accepted: 10/15/2015] [Indexed: 06/06/2023]
Abstract
We explored the use of a hybrid filler consisting of graphite nanoplatelets (GNPs) and single walled carbon nanotubes (SWCNTs) in a polyamide 6 (PA 6) matrix. The composites containing PA 6, powdered GNP, and SWCNT were melt-processed and the effect of filler content in the single filler and hybrid filler systems on the thermal conductivity of the composites was examined. The thermal diffusivities of the composites were measured by the standard laser flash method. Composites containing the hybrid filler system showed enhanced thermal conductivity with values as high as 8.8 W (m · K)-1, which is a 35-fold increase compared to the thermal conductivity of pure PA 6. Thermographic images of heat conduction and heat release behaviors were consistent with the thermal conductivity results, and showed rapid temperature jumps and drops, respectively, for the composites. A composite model based on the Lewis-Nielsen theory was developed to treat GNP and SWCNT as two separate types of fillers. Two approaches, the additive and multiplicative approaches, give rather good quantitative agreement between the predicted values of thermal conductivity and those measured experimentally.
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Affiliation(s)
- Sung Min Ha
- Division of Advanced Materials, Korea Research Institute of Chemical Technology, Daejeon 34114, Korea
- Department of Polymer Science and Engineering, Kyungpook National University, Daegu 41566, Korea
| | - O Hwan Kwon
- Division of Advanced Materials, Korea Research Institute of Chemical Technology, Daejeon 34114, Korea
| | - Yu Gyeong Oh
- Division of Advanced Materials, Korea Research Institute of Chemical Technology, Daejeon 34114, Korea
- Department of Chemical Convergence Materials and Nanomaterials Science and Engineering, University of Science and Technology, Daejeon 34113, Korea
| | - Yong Seok Kim
- Division of Advanced Materials, Korea Research Institute of Chemical Technology, Daejeon 34114, Korea
- Department of Chemical Convergence Materials and Nanomaterials Science and Engineering, University of Science and Technology, Daejeon 34113, Korea
| | - Sung-Goo Lee
- Division of Advanced Materials, Korea Research Institute of Chemical Technology, Daejeon 34114, Korea
| | - Jong Chan Won
- Division of Advanced Materials, Korea Research Institute of Chemical Technology, Daejeon 34114, Korea
- Department of Chemical Convergence Materials and Nanomaterials Science and Engineering, University of Science and Technology, Daejeon 34113, Korea
| | - Kwang Soo Cho
- Department of Polymer Science and Engineering, Kyungpook National University, Daegu 41566, Korea
| | - Byoung Gak Kim
- Division of Advanced Materials, Korea Research Institute of Chemical Technology, Daejeon 34114, Korea
- Department of Chemical Convergence Materials and Nanomaterials Science and Engineering, University of Science and Technology, Daejeon 34113, Korea
| | - Youngjae Yoo
- Division of Advanced Materials, Korea Research Institute of Chemical Technology, Daejeon 34114, Korea
- Department of Chemical Convergence Materials and Nanomaterials Science and Engineering, University of Science and Technology, Daejeon 34113, Korea
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Lee SS, Kim SK, Won JC, Kim YH, Kim SH. Reconfigurable Photonic Capsules Containing Cholesteric Liquid Crystals with Planar Alignment. Angew Chem Int Ed Engl 2015; 54:15266-70. [DOI: 10.1002/anie.201507723] [Citation(s) in RCA: 66] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2015] [Indexed: 11/06/2022]
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Lee SS, Kim SK, Won JC, Kim YH, Kim SH. Reconfigurable Photonic Capsules Containing Cholesteric Liquid Crystals with Planar Alignment. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201507723] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Lee HL, Kwon OH, Ha SM, Kim BG, Kim YS, Won JC, Kim J, Choi JH, Yoo Y. Thermal conductivity improvement of surface-enhanced polyetherimide (PEI) composites using polyimide-coated h-BN particles. Phys Chem Chem Phys 2015; 16:20041-6. [PMID: 25123585 DOI: 10.1039/c4cp02730b] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In this study, we investigated the thermal conductivities and mechanical properties of polyetherimide (PEI) composites using polyimide (PI)-coated h-BN (PI-BN) particles. We found that PI-coated h-BN effectively increased adhesion with the PEI matrix, imparting enhanced mechanical and thermal stability and thermal conductivity with increasing BN content. The thermal conductivity of the PEI composite containing 60 wt% PI-BN was 3.3 W m(-1) K(-1), while the thermal conductivity of the PEI/BN composite without modification was 2.6 W m(-1) K(-1). The PEI/PI-BN composites show higher impact strengths than the PEI/BN composites because of less BN particle agglomeration and good wettability between PEI and h-BN. The results indicate that the PI-coated BN incorporated into the PEI matrix effectively enhances the thermal conductivity and mechanical properties of the PEI composites.
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Affiliation(s)
- Hoing Lae Lee
- Advanced Functional Materials Research Group, Korea Research Institute of Chemical Technology, Daejeon 305-600, Republic of Korea.
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Lee SS, Kim B, Kim SK, Won JC, Kim YH, Kim SH. Robust microfluidic encapsulation of cholesteric liquid crystals toward photonic ink capsules. Adv Mater 2015; 27:627-633. [PMID: 25323332 DOI: 10.1002/adma.201403271] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2014] [Revised: 08/19/2014] [Indexed: 05/28/2023]
Abstract
Robust photonic microcapsules are created by microfluidic encapsulation of cholesteric liquid crystals with a hydrogel membrane. The membrane encloses the cholesteric core without leakage in water and the core exhibits pronounced structural colors. The photonic ink capsules, which have a precisely controlled bandgap position and size, provide new opportunities in colorimetric micro-thermometers and optoelectric applications.
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Affiliation(s)
- Sang Seok Lee
- Department of Chemical and Biomolecular Engineering (BK21+ Program), KAIST, Daejeon, 305-701, Korea
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Kim A, Jang KS, Kim J, Won JC, Yi MH, Kim H, Yoon DK, Shin TJ, Lee MH, Ka JW, Kim YH. Solvent-free directed patterning of a highly ordered liquid crystalline organic semiconductor via template-assisted self-assembly for organic transistors. Adv Mater 2013; 25:6219-25. [PMID: 23963897 DOI: 10.1002/adma.201302719] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2013] [Revised: 07/19/2013] [Indexed: 05/23/2023]
Abstract
Highly ordered organic semiconductor micropatterns of the liquid-crystalline small molecule 2,7-didecylbenzothienobenzothiophene (C10 -BTBT) are fabricated using a simple method based on template-assisted self-assembly (TASA). The liquid crystallinity of C10 -BTBT allows solvent-free fabrication of high-performance printed organic field-effect transistors (OFETs).
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Affiliation(s)
- Aryeon Kim
- Advanced Functional Materials Research Group, KRICT, Daejeon, 305-600, Korea
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Yoo Y, Lee HL, Ha SM, Jeon BK, Won JC, Lee SG. Effect of graphite and carbon fiber contents on the morphology and properties of thermally conductive composites based on polyamide 6. POLYM INT 2013. [DOI: 10.1002/pi.4534] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Youngjae Yoo
- Advanced Functional Materials Research Group; Korea Research Institute of Chemical Technology; Daejeon 305-600 Korea
| | - Hoing Lae Lee
- Advanced Functional Materials Research Group; Korea Research Institute of Chemical Technology; Daejeon 305-600 Korea
| | - Sung Min Ha
- Advanced Functional Materials Research Group; Korea Research Institute of Chemical Technology; Daejeon 305-600 Korea
| | - Byung Kuk Jeon
- Advanced Functional Materials Research Group; Korea Research Institute of Chemical Technology; Daejeon 305-600 Korea
| | - Jong Chan Won
- Advanced Functional Materials Research Group; Korea Research Institute of Chemical Technology; Daejeon 305-600 Korea
| | - Sung-Goo Lee
- Advanced Functional Materials Research Group; Korea Research Institute of Chemical Technology; Daejeon 305-600 Korea
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Kim TN, Kim JM, Won JC, Park MS, Lee SK, Yoon SH, Kim HR, Ko KS, Rhee BD. A decision tree-based approach for identifying urban-rural differences in metabolic syndrome risk factors in the adult Korean population. J Endocrinol Invest 2012; 35:847-52. [PMID: 22293132 DOI: 10.3275/8235] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
AIM The purpose of this study was to explore the difference in the pattern of metabolic syndrome (MetS) in urban and rural populations in Korea using data mining techniques. SUBJECTS AND METHODS In total, 1013 adults >30 yr of age from urban (184 males and 313 females) and rural districts (211 males and 305 females) were recruited from Gyeongsangnam-do, Korea. Modified National Cholesterol Education Program Adult Treatment Panel III criteria were used to identify individuals with MetS. We applied a decision tree analysis to elucidate the differences in the clustering of MetS components between the urban and rural populations. RESULTS The prevalence of MetS was 33.2% and 35.2% in urban and rural districts, respectively (p=0.598). The decision-tree approach revealed that the combination of high serum triglycerides (TG) + high systolic blood pressure (SBP), high TG + low HDL cholesterol, and high waist circumference (WC) + high SBP + high fasting plasma glucose (FPG) were strong predictors of MetS in the urban population, whereas the combination of TG + SBP + WC and SBP + WC + FPG showed high positive predictive value for the presence of MetS in the rural population. CONCLUSIONS Although no significant difference was found for the prevalence of MetS between the two populations, the differences in the clustering pattern of MetS components in urban and rural districts in Korea were identified by decision tree analysis. Our findings may serve as a basis to design necessary population-based intervention programs for prevention and progression of MetS and its complications in Korea.
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Affiliation(s)
- T N Kim
- Department of Internal Medicine, Cardiovascular and Metabolic Disease Center, Haeundae Paik Hospital, Inje University College of Medicine, Busan, Republic of Korea
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Won JC, Kwon HS, Kim CH, Lee JH, Park TS, Ko KS, Cha BY. Prevalence and clinical characteristics of diabetic peripheral neuropathy in hospital patients with Type 2 diabetes in Korea. Diabet Med 2012; 29:e290-6. [PMID: 22519862 DOI: 10.1111/j.1464-5491.2012.03697.x] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
AIMS Diabetic peripheral neuropathy is a common complication of diabetes. This cross-sectional study investigated the prevalence and clinical characteristics of this neuropathy in patients with Type 2 diabetic mellitus treated at hospitals in Korea. METHODS Questionnaires and medical records were used to collect data on 4000 patients with Type 2 diabetes from the diabetes clinics of 40 hospitals throughout Korea. Diabetic peripheral neuropathy was diagnosed based on a review of medical records or using the Michigan Neuropathy Screening Instrument score and monofilament test. RESULTS The prevalence of neuropathy was 33.5% (n = 1338). Multivariate analysis revealed that age, female sex, diabetes duration, lower glycated haemoglobin, treatment with oral hypoglycaemic agents or insulin, presence of retinopathy, history of cerebrovascular or peripheral arterial disease, presence of hypertension or dyslipidaemia, and history of foot ulcer were independently associated with diabetic peripheral neuropathy. Of the patients with neuropathy, 69.8% were treated for the condition and only 12.6% were aware of their neuropathy. CONCLUSION There was a high prevalence of peripheral neuropathy in patients with Type 2 diabetes in Korea and those patients were far more likely to have complications or co-morbidities. The proper management of diabetic peripheral neuropathy deserves attention from clinicians to ensure better management of diabetes in Korea.
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Affiliation(s)
- J C Won
- Department of Internal Medicine, Cardiovascular and Metabolic Disease Centre, College of Medicine, Inje University, Seoul, Korea
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Park JY, Oh KO, Won JC, Han H, Jung HM, Kim YS. Facile fabrication of superhydrophobic coatings with polyimide particles using a reactive electrospraying process. ACTA ACUST UNITED AC 2012. [DOI: 10.1039/c2jm32210b] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Kim CJ, Oh KW, Rhee EJ, Kim KH, Jo SK, Jung CH, Won JC, Park CY, Lee WY, Park SW, Kim SW. Relationship between body composition and bone mineral density (BMD) in perimenopausal Korean women. Clin Endocrinol (Oxf) 2009; 71:18-26. [PMID: 19178508 DOI: 10.1111/j.1365-2265.2008.03452.x] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
OBJECTIVES Osteoporosis is a disease that increases the fracture rates and it is the major cause of increased mortality and morbidity in the elderly people. To determine which component of body composition is most important to bone health, we analysed the relationship between elements of the body composition and bone mineral density (BMD) in Korean women. DESIGN Cross-sectional clinical study. PATIENTS Totally 1694 women (mean age 51 years) were selected from subjects who participated in a medical check-up program. MEASUREMENTS Body composition analysis was performed by segmental bioelectric impedance method and lean mass, fat mass and per cent body fat measured. Waist: hip ratio (WHR) was assessed as a marker for visceral fat. Lumbar spine (L-spine) BMD was measured by dual X-ray absorptiometry (DEXA). As menopausal status could not be confirmed in all subjects, we divided the subjects into two groups according to the age > 50 years and < 50 years. RESULTS Among the entire population, 599 subjects (35.4%) were osteopaenic and 229 subjects (13.5%) were osteoporotic. The bivariate correlation among the variables showed that weight had the highest correlation with fat mass. Mean lean mass was decreased and the WHR increased as the subjects progressed from normal to osteoporotic status; fat mass was the highest among the osteopaenic subjects. L-spine BMD showed a positive correlation with lean mass, and a negative correlation with WHR by bivariate correlation analysis. However, fat mass had a negative correlation with L-spine BMD only after adjustment for age and weight. Multiple regression analysis with L-spine BMD as the dependent variable showed that age, height, fasting insulin, lean mass and WHR were significant determinants of the L-spine BMD (R(2) = 0.170, P < 0.05). CONCLUSION In this Korean female population, L-spine BMD showed a consistently positive correlation with lean mass and a negative correlation with WHR. Fat mass failed to show any consistent correlation with L-spine BMD in this study population.
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Affiliation(s)
- C J Kim
- Department of Endocrinology, Kangbuk Samsung Hospital Sungkyunkwan University, School of Medicine, Seoul, Korea
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Lee YW, Won JC, Ki CS, Lee HY, Ahn HS, Lee YK, Kim YH, Kim CH. Clinical and genetic analysis of a Korean patient with late-onset X-linked adrenal hypoplasia congenita and hypogonadotropic hypogonadism: identification of a novel mutation in the NR0B1 gene. J Int Med Res 2008; 36:357-61. [PMID: 18380948 DOI: 10.1177/147323000803600220] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Adrenal hypoplasia congenita (AHC) is caused by mutations in the NR0B1 gene on chromosome Xp21.3-p21.2. It manifests as X-linked primary adrenal failure in early infancy or childhood and as hypogonadotropic hypogonadism (HHG) at puberty. Although studies of AHC patients and mutations in the NR0B1 gene have been reported throughout the world, there has previously been only one other case report from Korea. We encountered a 23-year old Korean male with delayed-onset AHC/HHG who had been previously diagnosed with adrenal insufficiency of unknown aetiology at age 13 years. Delayed puberty and incomplete HHG were observed. Direct sequencing of the NR0B1 gene revealed the patient to have a novel insertion mutation (c.959_960insT; Leu321ProfsX68). Although AHC is believed to be rare, it should be considered in a differential diagnosis of patients showing late-onset primary adrenal insufficiency.
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Affiliation(s)
- Y-W Lee
- Department of Laboratory Medicine and Genetics, Soonchunhyang University Bucheon Hospital and Soonchunhyang University College of Medicine, Bucheon, South Korea
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Lee ES, Hong SK, Kim YS, Lee JH, Won JC. Preparation and characteristics of cross-linkable polysulfone having methylene methacrylate side-chain. J Appl Polym Sci 2008. [DOI: 10.1002/app.27944] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Hur SR, Kim YS, Won JC, Lee JH, Jung HM. Hollow hybrid spheres with silica inner shell for non-deformable, core exchangeable properties. Chem Commun (Camb) 2008:5405-7. [DOI: 10.1039/b811724a] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Kim DW, Kang Y, Jin MY, Seok S, Won JC, Lee C, Yi J, Kim J, Kang J, Shin JS. Porous polyimide films prepared by thermolysis of porogens with hyperbranched structure. J Appl Polym Sci 2004. [DOI: 10.1002/app.20624] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Kim JH, Kim YH, Kim YJ, Won JC, Choi KY. Synthesis and characterization of novel aromatic condensation polymers containing rigid benzoxazole pendent groups. J Appl Polym Sci 2004. [DOI: 10.1002/app.13629] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Kim JH, Lee JK, Kim YJ, Won JC, Choi KY. Synthesis and characterization of poly(amic acid)s from a novel aromatic diamine with bilaterally attached benzoxazole groups. Macromol Res 2002. [DOI: 10.1007/bf03218312] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Suh DH, Won JC, Kim DK, Jung JC. A novel synthesis of polysulfide by phase transfer-catalyzed terpolymerization of malononitrile, carbon disulfide, and α,α′-dichloro-p-xylene. ACTA ACUST UNITED AC 1988. [DOI: 10.1002/pol.1988.140260204] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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