• Title/Summary/Keyword: polymer interface

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Trend of Bioadhesives (III) -Pressure-sensitive adhesives for medical application (생체용 접착제의 연구동향(III) - 의료용 감압 접착제의 최근의 개발동향 -)

  • Jeong, Hyun-Cheol;Cho, Chang-Min;You, Jong-Sun;Ha, Chang-Sik;Cho, Won-Jei
    • Journal of Adhesion and Interface
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    • v.2 no.2
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    • pp.28-34
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    • 2001
  • 의료용 감압 접착제(PSAs)는 접착되어지는 피부가 매우 다양한 타입이 있고 그 응용범위가 다양하므로 요구되어지는 것들이 매우 까다롭다. 본 총설은 의료용 PSAs의 특이한 성질의 합성을 포함하여 1985년 이후의 주된 화학적 개발동향에 그 초점을 두고 있다. 응집력 향상으로 Hot melt형 접착제를 주로 검토할 것이다.

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Methods to Formulate Waterborne Conjugated Polymer Nanoparticles (수분산 공액고분자 나노입자의 합성 방법론)

  • Seungju Kang;Boseok Kang
    • Journal of Adhesion and Interface
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    • v.24 no.1
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    • pp.1-8
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    • 2023
  • A conjugated polymer is the next-generation emerging semiconductor material that can be applied in various fields, from organic electronics to biomedical applications. However, its low solubility in an aqueous medium has made the use of toxic organic solvents inevitable, thereby leading to formulation of conjugated polymers in the form of waterborne nanoparticles. This review paper discusses two principles of nanoparticle formation and representative methods for synthesizing conjugated polymer nanoparticles.

Preparation and Characterization of Fluorenyl Polymer Electrolyte Membranes Containing PFCB Groups (PFCB Group을 포함한 Fluorene계 고분자 전해질막 제조 및 특성연구)

  • Kim Jeong-Hoon;Kim Dong-Jin;Chang Bong-Jun;Shin Chong-Kyu;Lee Soo-Bok;Joo Hyeok-Jong
    • Membrane Journal
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    • v.16 no.1
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    • pp.16-24
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    • 2006
  • We report on the preparation and characterization of sulfonated polymer membranes containing perfluorocyclobutane (PFCB) units and fluorene units. The polymers were prepared through three synthetic steps, that is, the synthesis of a trifluorovinylether-terminated monomer, its thermal polymerization, and post-sulfonation using chlorosulfonic acid. A series of sulfonated polymers with different ion exchange capacity (IEC) were prepared by changing the content of chlorosulfonic acid during the post-sulfonation reaction. All the synthesized compounds were characterized by FT-IR, $^{1}H-NMR,\;^{19}F-NMR$, and Mass spectroscopy. As the content of chlorosulfonic acid increased, the SD, IEC, water uptake, and ion conductivity of the sulfonated polymer membranes increased. The sulfonated polymer 4 showed higher values of ion conductivity than the Nafion-$115^{\circledR}$ in a wide range of temperatures ($25{\sim}80^{\circ}C$).

Fabrication of Carbon Nanotubes Monolayer Film using Liquid/Liquid Interface

  • Matsui, Jun;Yamamoto, Kohei;Inokuma, Nobuhiro;Orikasa, Hironori;Kyotani, Takashi;Miyashita, Tokuji
    • Proceedings of the Polymer Society of Korea Conference
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    • 2006.10a
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    • pp.279-279
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    • 2006
  • We report a fabrication of carbon nanotube (CNT) monolayer thin film using liquid-liquid interface. The multiwalled carbon nanotube (MWCNT), which were synthesized by the alumina template method formed a monolayer at the liquid-liquid interface after sonicating the MWCNT water-oil dispersion. Moreover, with the addition of ethanol, the MWCNT monlayer was also formed at the liquid-liquid interface. The monolayer is transferable onto solid substrates and the transferred film was observed using atomic force microscopy (AFM)

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Wetting of Galvanised Steel by An Epoxy Adhesive: Effects of Surface Oil

  • Shanahan, M.E.R.;Greiveldinger, M.
    • Journal of Adhesion and Interface
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    • v.3 no.1
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    • pp.20-23
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    • 2002
  • The wetting properties of an uncured epoxy resin on both clean and oiled, galvanised steel have been studied. Since the polymer is very viscous at ambient temperature, and also with an aim to simulate industrial conditions, the spreading of drops of resin during a heating cycle (temperature increase at $10^{\circ}C/min$) was recorded and analysed. On clean steel, a contact angle, ${\theta}$, vs time, t, plot shows sigmoidal behaviour, whereas on the oiled substrate, spreading almost ceases in an intermediate stage. This strange behaviour is attributed to significant oil absorption by the polymer.

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Role of Charges of the Surface-grafted Polymer Chains for Aqueous Lubrication at a Nonpolar Interface

  • Ron, Troels;Madsen, Jan Busk;Nikorgeorgos, Nikolaos;Lee, Seunghwan
    • Tribology and Lubricants
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    • v.30 no.5
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    • pp.247-255
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    • 2014
  • Charged polymer chains, i.e., polyelectrolytes, are known to show superior aqueous lubricating properties compared to those of neutral polymer chains, especially in brush conformation. This is primarily because of the incorporation of a large amount of counterions within the polymer layers and the consequently increased osmotic pressure. However, this effect is active only when the polymer chains remain immobilized even under tribostress, which is not realistic for high-contact pressure tribological applications, especially when they are irreversibly immobilized on tribopair surfaces. In contrast, with free polymers, which can be included as surface-active additives in the base lubricant (water), long-term lubricating performance based on "self-healing" properties is readily expected. In order to assess whether the superior aqueous lubricating properties of polyelectrolyte chains are valid for free polymers too, this study reviews recent studies on the tribological properties of many charged biopolymer and synthetic copolymers at a nonpolar, hydrophobic interface. In contrast to the irreversibly immobilized polyelectrolyte chains, free polyelectrolyte chains show inferior aqueous lubricating properties compared to their neutral counterparts owing to charge accumulation and the consequently impeded surface adsorption on the nonpolar surface. Nevertheless, bovine submaxillary mucin (BSM), a representative biopolymer, shows a sufficiently effective surface adsorption and aqueous lubricating capabilities even at neutral pH without losing the polyanionic characteristics.

Curing Properties of UV-LED Curable Color Coating (UV-LED 경화형 칼라 코팅의 경화특성 연구)

  • Ho, Shin-Chan;Kim, Jong-Gu;Hong, Jin-Who;Ahn, Tae-Jung;Kim, Hyun-Kyoung
    • Journal of Adhesion and Interface
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    • v.13 no.1
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    • pp.31-37
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    • 2012
  • In this study, we investigated the curing properties of UV-LED curable color coating. Specially, the effects of UV-LED wavelength (365, 395, and 405 nm), inert gas, the concentration of photosensitizer, and dual curing on the curing behavior of UV-LED coating systems were studied. The photopolymerization behaviors and the unreacted acrylate groups at Film-air (FA) interface and Film-substrate (FS) interface were investigated by photo differential scanning calorimetry (Photo-DSC) and Fourier-transform infrared spectroscopy with attenuated total reflection (FT-IR/ATR), respectively. Photo-DSC results showed that the heat flow and the ultimate conversion for coating system cured by 405 nm UV-LED were higher than the corresponding values for coating systems cured by 395 and 365 nm UV-LED. FT-IR/ATR results showed that the UV-LED curing systems improved interior and through curing of the coating film, but significantly are affected by oxygen inhibition at FA-interface. The inert environment such as nitrogen purging and the dual curing improved the surface and interior curing of the coating films.

Interfacial Phenomena of Lignocellulose Fiber/Thermoplastic Polymer Composites (리그노셀룰로오스 섬유/열가소성 고분자 복합재의 계면 현상)

  • Son, Jungil;Yang, Han-Seung;Kim, Hyun-Joong
    • Journal of Adhesion and Interface
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    • v.3 no.4
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    • pp.44-52
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    • 2002
  • Composite materials are created by combining two or more component to achieve desired properties which could not be obtained with the separate components. The use of reinforcing fillers, which can reduce material costs and improve certain properties, is increasing in thermoplastic polymer composites. Currently, various inorganic fillers such as talc, mica, clay, glass fiber and calcium carbonate are being incorporated into thermoplastic composites. Nevertheless, lignocellulose fibers have drawn attention due to their abundant availability, low cost and renewable nature. In recent, interest has grown in composites made from lignocellulose fiber in thermoplastic polymer matrices, particularly for low cost/high volume applications. In addition to high specific properties, lignocellulose fibers offer a number of benefits for lignocellulose fiber/thermoplastic polymer composites. These include low hardness, which minimize abrasion of the equipment during processing, relatively low density, biodegradability, and low cost on a unit-volume basis. In spite of the advantage mentioned above, the use of lignocellulose fibers in thermoplastic polymer composites has been plagued by difficulties in obtaining good dispersion and strong interfacial adhesion because lignocellulose fiber is hydrophilic and thermoplastic polymer is hydrophobic. The application of lignocellulose fibers as reinforcements in composite materials requires, just as for glass-fiber reinforced composites, a strong adhesion between the fiber and the matrix regardless of whether a traditional polymer matrix, a biodegradable polymer matrix or cement is used. Further this article gives a survey about physical and chemical treatment methods which improve the fiber matrix adhesion, their results and effects on the physical properties of composites. Coupling agents in lignocellulose fiber and polymer composites play a very important role in improving the compatibility and adhesion between polar lignocellulose fiber and non-polar polymeric matrices. In this article, we also review various kinds of coupling agent and interfacial mechanism or phenomena between lignocellulose fiber and thermoplastic polymer.

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