Research Trends in Polymer Materials for Use in Lightweight Vehicles

류민영,최태균 한국정밀공학회 2015 International Journal of Precision Engineering and Vol. No.

Weight reduction of vehicle is very important because vehicle weight directly affects energy consumption. Studies researchinglightweight vehicle manufacturing process that use polymers are reviewed in this paper. Approaches reducing the weights of vehiclesusing polymers most frequently involve replacing ferrous and non-ferrous metals with polymers and increasing the specific strengthsand rigidities of polymers. Researches into polymers for use in lightweight vehicle are classified into high performance polymers,polymers for weight reduction, reinforced polymer composites, polymer sandwich panels, and polymer/metal hybrid systems. A diverserange of polymer materials can be used to make vehicle components and the manufacturing methods required to produce and workthose materials vary greatly. Shaping processes must be chosen according to the materials being used and the product design. Replacement of metal products with polymer materials in current vehicles is limited. Large amounts of lightweight materials, suchas polymers, will be greatly used to construct newly developed vehicles, including electric and electric/hybrid vehicles.

나노 MMT-폴리머 복합체를 이용한 폴리머 콘크리트의 강도 특성

조병완(Jo Byung-Wan),문린곤(Moon Rin-Gon),박승국(Park Seung-Kook) 대한토목학회 2006 대한토목학회논문집 A Vol.26 No.4A

Polymer composite are increasingly considered as structural components for use in civil engineering, on account of their enhanced strength-to-weight ratios. Unsaturated polyester (UP) resin have been widely used for the matrix of composites such as FRP and polymer composite, due to its excellent adhesive. Polymer nanocomposites are new class of composites derived from the nano scale inorganic particles with dimensions typically in the range of 1 to 1000 nm that are dispersed in the polymer matrix homogeneously. Owing to the high aspect ratio of the fillers, mechanical, thermal, flame, retardant and barrier properties are enhanced without significant loss of clarity, toughness or impact strength. To prepare the MMT (Montmorillonite)-UP exfoliated nanocomposites, UP was mixed with MMT at 60℃ for 3 hours by using pan mixer. XRD (X-ray diffraction) pattern of the composites and TEM (Transmission Electron Micrographs) showed that the interlayer spacing of the modified MMT were exfoliated in polymer matrix. The mechanical properties also supported these findings, since in general, tensile strength, modulus with modified MMT were higher than those of the composites with unmodified MMT. The thermal stability of MMT-UP nanocomposite is better than that of pure UP, and its glass transition temperature is higher than that of pure UP. The polymer concrete made with MMT-UP nanocomposite has better mechanical properties than of pure UP. Therefore, it is suggested that strength and elastic modulus of polymer concrete was found to be positively tensile strength and tensile modulus of the MMT-UP nanocomposites. 폴리머 복합체는 우수한 강도와 내구성으로 건설현장에서 프리캐스트 부재 및 보수, 보강재로서 널리 쓰이고 있어 폴리머 복합체의 경제성 및 성능 향상에 관한 연구가 이루어지고 있다. 폴리머 나노 복합체는 나노미터 수준의 크기를 가진 Clay 등의 무기 물질을 나노분산 상으로 폴리머에 균일 혼합시킨 것으로 산업적 응용기능성 변에서 뿐만 아니라 재료 및 공학 분야에서도 많은 관심을 가지고 있다. 그리고 기존의 복합체 보다 1/10 혹은 그 이상의 낮은 함량의 분산상만으로도 더 우수한 강도와 역학적 특성 및 열안정성을 나타낸다. 본 실험에서는 폴리머 복합체의 성능을 향상시키고자 유기화된 몬모릴로나이트(MMT)와 유기화 되지 않은 몬모릴로나이트(MMT)를 사용하여 박리된 MMT-UP 나노 복합체를 제조하였다. XRD와 TEM실험결과, Cloisite 30B-UP 나노 복합체에서 층과 층 사이가 100Å 이상 떨어져 단일층으로 분산되었기 때문에 박리가 되었음을 알 수 있었다. 또한 역학적 특성은 기존복합체보다 인장강도와 인장탄성계수을 비교하였을 때 매우 향상됨을 알 수 있었고 열적 특성도 기존복합체보다 우수한 함을 나타내었다. 박리정도가 우수한 MMT-UP 복합체로 제조한 폴리머 콘크리트에서도 순수한 UP를 사용한 것보다 역학적 특성이 두드러졌다. 또한 폴리머 콘크리트의 강도와 탄성계수는 MMT-UP 복합체의 인장강도 및 인장탄성계수와 상관성을 갖는 것으로 판단된다.

Polymer nanocomposites reinforced with multi-walled carbon nanotubes for semiconducting layers of high-voltage power cables

Jeong, Kwang-Un,Lim, Jee Young,Lee, Jong-Young,Kang, Seong Lak,Nah, Changwoon John Wiley Sons, Ltd. 2010 Polymer international Vol.59 No.1

<P>Polymer nanocomposites reinforced with multi-walled carbon nanotubes (MWCNTs) have been newly introduced for semiconducting layers of high-voltage electrical power cables. Homogeneity of the MWCNT-reinforced polymer nanocomposites was achieved by solution mixing, and their mechanical, thermal and electrical properties were investigated depending on the type of polymer. By changing the polymer matrix, the volume resistance of the MWCNT-reinforced polymer nanocomposites could be varied by more than four orders of magnitude. Through systematic experiments and analysis, two possible factors affecting the volume resistance were found. One is the degree of crystallinity of the polymer used and the other is the change of MWCNT morphology under strain. By increasing the degree of crystallinity above a certain level, the volume resistance linearly increased. The MWCNTs embedded in the nanocomposites gradually protruded through the surface on stretching the sample and reversibly returned back to the original positions at a relatively small strain (below 20%). Based on the criteria of tensile properties and volume resistance, a poly[ethylene-co-(ethyl acrylate)]/MWCNT nanocomposite was selected as the best candidate for the semiconducting layers of high-voltage electrical power cables. Copyright © 2009 Society of Chemical Industry</P> <B>Graphic Abstract</B> <P>Based on the criteria of tensile properties and volume resistance, poly[ethylene-co-(ethyl acrylate)] (EEA)/MWCNT nanocomposite was selected as the best candidate for a SCL of high electrical power cables. <img src='wiley_img/09598103-2010-59-1-PI2696-gra001.gif' alt='wiley_img/09598103-2010-59-1-PI2696-gra001'> </P>

Bioactivity and osteoblast responses of novel biomedical nanocomposites of bioactive glass nanofiber filled poly(lactic acid)

Kim, Hae-Won,Lee, Hae-Hyoung,Chun, Gae-Sig Wiley Subscription Services, Inc., A Wiley Company 2008 Journal of biomedical materials research. Part A Vol.a85 No.3

<P>Biomedical nanocomposites constituted of bioactive ceramic and resorbable polymer have shown promise for the successful regeneration of bone tissues. We developed herein a novel nanocomposite made up of a bioactive glass in a nanofibrous form and a degradable synthetic polymer, poly(lactic acid) (PLA). The glass nanofiber with a bioactive composition was generated via an electrospinning process with an average diameter of ∼320 nm. The nanofiber was homogenized with PLA solution at various concentrations (up to 35% nanofiber), followed by drying and thermal pressing to produce dense nanocomposites. The nanocomposites showed an internal morphology of uniformly dispersed nanofibers within the PLA matrix. The nanocomposites induced rapid formation of a hydroxycarbonate apatite layer on the surface under a simulated physiological medium. As the amount of bioactive nanofiber increased (from 5 to 25%), the in vitro bioactivity of the nanocomposite was improved. The osteoblast responses to the nanocomposites (compositions with 5 and 25% nanofiber) were assessed in terms of cell proliferation, differentiation, and mineralization. Osteoblasts attached and grew well on the nanocomposites and secreted collagen protein at initial culturing periods. The differentiation of cells, as assessed by the expression of alkaline phosphatase, was significantly improved on the nanocomposites as compared to those on pure PLA. Moreover, the mineralized product by the cells was observed to be significantly higher on the nanocomposites with respect to pure PLA. The newly developed nanocomposite constituted of bioactive nanofiber and degradable polymer is considered as a promising bone regeneration matrix with its excellent bioactivity and osteoblast responses. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2008</P>

고분자 전해질과 고분자 나노복합체를 활용한 올레핀 촉진수송 분리막에 대한 총설

Sang Wook Kang 한국막학회 2016 멤브레인 Vol.26 No.3

본 총설에서는 고분자와 은염으로 구성된 고분자 전해질 분리막과 장시간 안정성을 해결하기 위한 방안들이 정리 되었다. 특히 이온성 액체를 활용하여 AgNO3를 새로운 운반체로 사용하기 위한 방안, 새로운 고분자 매트릭스로서 poly(ethylene phthalate) (PEP)를 활용하는 방안과 가장 최근 알루미늄 염을 활용하여 운반체의 안정성을 부여하는 연구결과들이 정 리되었다. 올레핀 촉진수송을 위한 고분자 나노복합체 분리막의 경우, 운반체인 은 나노입자 표면을 극성화시킬 수 있는 전자 수용체의 종류와 특징들이 소개되었으며, 최근 투과도 성능을 향상시킬 수 있는 연구결과들이 정리되었다. In this short review, the polymer electrolyte membranes consisting of polymer and Ag salts were introduced and various approaches to solve the long-term stability were summarized. In particular, utilizing AgNO3 as carriers with ionic liquid, the replacement of polymer matrix as poly(ethylene phthalate) (PEP) for strong coordinative interactions with Ag ions and the introduction of Al(NO3)3 to polymer/AgBF4 complexes were introduced for long-term stable facilitated olefin transport membranes. For the polymer nanocomposite membranes, the role of electron acceptors as polarizer on the surface of AgNPs and the approach to solve the low permeance were introduced.

Synthesis of MWCNTs-core/thiophene polymer-sheath composite nanocables by a cationic surfactant-assisted chemical oxidative polymerization and their structural properties

Reddy, Kakarla Raghava,Jeong, Han Mo,Lee, Youngil,Raghu, Anjanapura Venkataramanaiah Wiley Subscription Services, Inc., A Wiley Company 2010 Journal of polymer science Part A, Polymer chemist Vol.48 No.7

<P>Multi-walled carbon nanotubes (MWCNTs)-core/thiophene polymer-sheath composite nanocables were synthesized by chemical oxidative polymerization of 3,4-ethylenedioxythiophene (EDOT) with oxidant (FeCl<SUB>3</SUB>) in the presence of cationic surfactant, deceyltrimethyl ammonium bromide (DTAB). In the polymerization process, DTAB surfactant molecules were adsorbed on the surface of MWCNTs and forms MWCNTs-DTAB soft template. Upon the addition of EDOT and oxidant, the polymerization take place on the surface of MWCNTs and PEDOT is gradually deposited on the surface of MWCNTs. The resulting MWCNTs-PEDOT nanocomposites have the nanocable structure. Nanocomposites were characterized by HRTEM, FE-SEM, XRD, XPS, TGA, FTIR and PL, respectively. The π-π interactions between PEDOT and MWCNTs enhancing the thermal and electrical properties of the nanocomposites with loading of MWCNTs. The temperature dependence conductivity measurements show that the conductivity of the nanocomposite decrease with a decrease of temperature, and conductivity-temperature relationship is well fit by the quasi-one dimensional variable range hopping mode. The mechanism for the formation of composite nanocables was explained on the basis of self- assembly of micelles. The reported self-assembly strategy for the synthesis of PEDOT-coated MWCNTs in micellar medium is a rapid, versatile, potentially scalable, stable, and making it useful for further exploitation in a varies types of applications. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 1477–1484, 2010</P> <B>Graphic Abstract</B> <P>The MWCNTs-thiophene polymer core-sheath composite nanocables were synthesized by chemical oxidative polymerization of 3,4-ethylenedioxythiophene (EDOT) with oxidant (FeCl<SUB>3</SUB>) in the presence of cationic surfactant, deceyltrimethyl ammonium bromide (DTAB) that acts as the structure-directing agen. In the polymerization process, DTAB surfactant molecules were adsorbed on the surface of MWCNTs and forms MWCNTs-DTAB soft template. On the addition of EDOT and oxidant, the polymerization takes place on the surface of MWCNTs, and PEDOT is gradually deposited on the surface of MWCNTs. The resulting nanocomposites have the nanocable structure as shown in the scheme. The structural, morphological, thermal, optical, and electrical properties of the synthesized nanocomposites were fully characterized by using various techniques. The mechanism for the formation of composite nanocables was explained on the basis of self-assembly of micelles. The reported self-assembly strategy for the synthesis of PEDOT-coated MWCNTs in micellar medium is a rapid, versatile, potentially scalable, stable, and making it useful for further exploitation in various types of applications. <img src='wiley_img_2010/0887624X-2010-48-7-POLA23883-gra001.gif' alt='wiley_img_2010/0887624X-2010-48-7-POLA23883-gra001'> </P>

Fabrication of Plasmon-Active Polymer-Nanoparticle Composites for Biosensing Applications

Abhinay Mishra,Abdul Rahim Ferhan,Chee Meng Benjamin Ho,Joohyun Lee,Dong-Hwan Kim,Young Jin Kim,Yong-Jin Yoon 한국정밀공학회 2021 International Journal of Precision Engineering and Vol.8 No.3

Polymer-nanoparticle composites find relevance in various fields ranging from optoelectronics to the biomedical sciences. Various efforts have been made to devise fabrication strategies that are simple, robust,and reproducible. Herein, we demonstrate a universal strategy to fabricate plasmon-active polymer-nanoparticle composites, exemplified by the incorporation of gold nanoparticles (AuNPs) into a triethylene glycol dimethacrylate (TEGDMA) polymer scaffold. The TEGDMA scaffold was synthesized on a planar glass support substrate via surface-initiated atomic transfer radical polymerization, followed by the immersion of the TEGDMA-coated glass substrate in a solution of AuNPs prepared via conventional wet-chemical synthesis. This led to the strong attachment of AuNPs to the TEGDMA nanolobes, which was confirmed by the UV absorption peak at 527 nm, due to localized surface plasmon resonance of AuNPs. More importantly, the nanolobe architecture facilitates nanoparticle trapping while allowing molecular access to the nanoparticle surface. This enabled us to further functionalize the incorporated AuNPs with thrombin binding aptamer and utilize the biofunctionalized polymer-nanoparticle composite as a thrombin sensor. The synergistic combination of metallic nanoparticles acting as a sensing module with a nonfouling polymer matrix acting both as a nonrigid scaffold and to screen biomolecules allowed the detection of thrombin with good sensitivity down to 0.01 ng/mL with a linear range over three orders of magnitude. Our work paves the way for the fabrication of reliable biomolecular sensors based on the polymer brush-nanoparticle architecture.

Organoclay/TLCP nanocomposites의 제조 및 특성

김원,최재곤,조병욱 조선대학교 생산기술연구소 2003 生産技術硏究 Vol.25 No.2

The organoclay/TLCP(Thermotropic Liquid Crystal Polymer) nanocomposites were prepared by in-situ polymerization. To discuss the effect of the organoclay contents on the polymer properties, we prepared organoclay/TLCP nanocomposites of 2, 5, 10wt% in organoclay contents. The organoclay/TLCP nanocomposites were characterized by scanning electron microscopy(SEM), X-ray diffractometer(XRD), dynamic mechanical thermal analysis (DMTA), differential scanning calorimetry (DSC), and thermogravimetric analyzer(TGA). The bending moduli of organoclay/TLCP nanocomposites were improved with increasing organoclay contents. The TLCPs and organoclay/TLCP nanocomposites showed the nematic phase above those melting ternperature(T_(m)). The TLCPs and organo clay/TLCP nanocomposite seem to act as plasticizers and nucleating agents in the matrix polymers.

Development of PMMA/TiO2 nanocomposites as excellent dental materials

Md. Alamgir,Ashis Mallick,G. C. Nayak,Santosh K. Tiwari 대한기계학회 2019 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.33 No.10

This paper presents the application of the in-situ synthesized nanocomposites of poly (methyl methacrylate) (PMMA) and TiO 2 for use as dental materials. TiO 2 nanoparticles with different percentages (1wt% and 2 wt%) were blended with PMMA through a melt compounding process. The prepared nanocomposites were characterized by a micro-indentation test, scratch test, and field emission scanning electron microscopy analysis. The effects of different vol. % of TiO 2 on the mechanical properties of the composites were studied. The evaluation of the mechanical properties of the composites revealed that the utilization of TiO 2 as a reinforcing agent strengthened the polymer. The morphological observation demonstrated the presence of significant adhesion between TiO 2 and the polymer matrixes with a homogeneous distribution of TiO 2 in the polymer matrix. The proper compatibilization between TiO 2 and the polymer matrix enhanced the mechanical properties. Overall, this work may pave the way for the production of a new compatibilized TiO 2 -based blend for dental applications.

Highly Precise Determination of Structural and Optical Parameters of an Innovative (PVA-VOCl) for Flexible Polymer-Semiconductor Devices

Fayez M. Ali,Fethi Maiz 한국고분자학회 2020 Macromolecular Research Vol.28 No.9

A novel polymer-semiconductor nanocomposites of polyvinyl alcoholoxovanadium chloride (PVA-VOCl) films have been successfully synthesized by the simple solution casting technique. XRD analysis of the prepared films confirms the formation of VOCl nanocrystals with different particle sizes distributed in the PVA polymer resulting in the increment in the crystalline phase of the whole structure of PVA-VOCl polymer nanocomposite. The Fourier transform infrared (FT-IR) spectroscopy measurements indicate the distribution of VOCl in the polymer matrix. The optical absorption spectra measurements exhibit a complete blocking of the UV range (200 - 400nm) due to VOCl dispersion in the polymer matrix. The optical gap E g of the films were determined with a high degree of precision using Tauc relation, Absorption spectra fitting and the new accurate geometric method show a strong decrease from 5.2 eV for pure PVA to 2.85 eV with increasing the VOCl level in the polymer film. In addition, the high-frequency refractive index estimated from the optical gap values exhibits a significant increase from 1.70 to 2.07. Our samples can be considered as an innovative flexible optical material for UV filters, optoelectronics, and photonics applications.