• Polymer Science and Technology
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• v.23 no.3
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• pp.282-288
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• 2012

• Proceedings of the Membrane Society of Korea Conference
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• 2005.05a
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• pp.93-94
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• 2005

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.26 no.1
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• pp.39-46
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• 2015

In this paper, a gas sensor using a modified $90^{\circ}$ hybrid coupler structure with conducting polymer which operates at 2.4 GHz is represented. Conducting polymers are used to the gas sensing material in proposed sensors. The conducting polymer varies its electrical property, such as work function and conductivity corresponding to the certain gas. To verify this variation of electrical property of conducting polymer at microwave frequencies, the conducting polymer is incorporated with the $90^{\circ}$ hybrid coupler structure, and this proposed sensor operates as reflection type variable attenuator and variable phase shifter. The conducting polymer is employed as impedence-variable transmission lines that cause a impedance mismatching between the general transmission line and conducting polymer. The experiment was conducted with 100 ppm ethanol gas at temperature of $28^{\circ}C$ and relative humidity of 85 %. As a result, the amplitude deviation of $S_{21}$ is 0.13 dB and the frequency satisfying ${\angle}S_{21}=360^{\circ}$ is shifted about 2.875 MHz.

• Proceedings of the Korean Fiber Society Conference
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• 2003.10a
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• pp.43-44
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• 2003

The new method for preparing hybrid fibers from aqueous solution is described. The method is based on interfacial polyionic complexation between the counter-charged polymers. Polysaccharides, chitosan and gellan, and polypeptides, poly(L-lysine) and poly(L-glutamic acid) were utilized as the components of the fibers. The chitosan-gellan and poly(L-lysine)-gellan hybrid fibers exhibited a high level biodegradability.

• Proceedings of the Korea Concrete Institute Conference
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• 2009.05a
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• pp.509-510
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• 2009

In strengthening reinforced concrete beams using fiber reinforced polymer sheets, brittle structural failures occur due to the linear stress-strain relationship of the fibers. Hybrid fiber reinforced polymer sheets using two different types of fibers were investigated in this study

• Macromolecular Research
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• v.15 no.2
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• pp.95-99
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• 2007

The most recent developments in two areas: (a) synthesis of inorganic particles with control over size and shape by polymer additives, and (b) synthesis of inorganic-polymer hybrid materials by bulk polymerization of blends of monomers with nanosized crystals are reviewed. The precipitations of inorganics, such as zinc oxide or calcium carbonate, in presence and under the control of bishydrophilic block or comb copolymers, are relevant to the field of Biomineralization. The application of surface modified latex particles, used as controlling agents, and the formation of hybrid crystals in which the latex is embedded in otherwise perfect crystals, are discussed. The formation of nano sized spheres of amorphous calcium carbonate, stabilized by surfactant-like polymers, is also discussed. Another method for the preparation of nanosized inorganic functional particles is the controlled pyrolysis of metal salt complexes of poly(acrylic acid), as demonstrated by the syntheses of lithium cobalt oxide and zinc/magnesium oxide. Bulk polymerization of methyl methacrylate blends, with for example, nanosized zinc oxide, revealed that the mechanisms of tree radical polymerization respond to the presence of these particles. The termination by radical-radical interaction and the gel effect are suppressed in favor of degenerative transfer, resulting in a polymer with enhanced thermal stability. The optical properties of the resulting polymer-particle blends are addressed based on the basic discussion of the miscibility of polymers and nanosized particles.

• Membrane Journal
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• v.15 no.1
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• pp.62-69
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• 2005

SEBS-clay hybrid membranes were prepared by melt intercalation method with internal mixer. In the hybrid, the amount of clay content was fixed to 5 phr. MMT was intercalated or exfoliated by the ionomer and it was confirmed by X-ray diffraction method. D-spacing of the characteristic peak from MMT plate in SAXD was moved and diminished. Gas permeability, mechanical properties and thermal properties of the SEBS-clay hybrid membranes were investigated. Gas permeability through the SEBS-clay hybrid membranes decreased due to increased tortuosity made by intercalation of clay in SEBS.

• Journal of Adhesion and Interface
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• v.20 no.4
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• pp.146-154
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• 2019

In this study, alkoxysilane-functionalized amphiphilic polymer (AFAP), which have hydrophilic segment and hydrophobic segment functionalized by alkoxysilane group at the same backbone, was synthesized and used as a dispersant and control agent for reaction rate in the preparation of colloidally stable organic-inorganic (O-I) hybrid sols. After reaction with fluorosilane compounds, fluorinated O-I hybrid sols were prepared and coated onto glass substrate to form hydrophobic O-I hybrid coating films through low-temperature curing process. Surface hardness and hydrophobicity of cured coating films were varied with type of solvent and composition of AFAP and fluorinated alkoxysilane compounds. At appropriate solvent and composition of fluorinated alkoxysilane compounds, O-I hybrid coating film having high transparency and surface hardness could be prepared, which could be applicable to cover window of solar cell and displays.

• Polymer(Korea)
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• v.30 no.5
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• pp.380-384
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• 2006

Polyhedral oligomeric silsesquioxanes (POSS) were used as starting materials for the preparation of hybrid materials with polystyrene (PS). Optically transparent hybrids were obtained in a wide range of weight ratios when phenyl groups were introduced to each corner of the silsesquioxane. In contrast, as cyclohexyl groups were introduced, the obtained hybrid materials with PS resulted in turbid films. The aromatic (${\pi}-{\pi}$) interaction was confirmed to be a quite effective tool for the synthesis of organic-Inorganic polymer hybrids with POSS. The obtained homogeneous and transparent hybrid films could be dissolved in solvents and East again without any separation. The homogeneity of polymer hybrids with POSS was supported by the result of scanning electron microscopy (SEM), X-ray diffraction (XRD), and differential scanning calorimetry (DSC), which demonstrated a nanometer-level integration of PS and POSS.

• Journal of Adhesion and Interface
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• v.5 no.1
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• pp.21-28
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• 2004

In this work, glass fiber/nylon 6 and woven glass fiber/nylon 6 composites have been fabricated using glass fiber reinforcements sized with 3-chloropropyltrimethoxysilane(CTMS) having a chloropropyl organo-functional group in the molecular chain end. The interfacial shear strength of glass fiber/nylon 6 composite was measured using a single fiber microbonding test and the interlaminar shear strength and the storage modulus of woven glass fabric/nylon 6 composites were measured using a short-warn shear test and a dynamic mechanical analysis, respectively, informing the effect of the concentration of CTMS on the properties. With increasing CTMS concentration, the interfacial properties of the composites were improved. The results on the interfacial shear strength, interlaminar shear strength, interlaminar failure pattern, and storage modulus with varying the CTMS concentration agree with each other.