• Journal of the Korean Vacuum Society
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• v.7 no.1
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• pp.72-76
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• 1998

A new gas-flow type reactor for plasma polymerization was developed to synthesize functional polymers, which enhances reaction of radicals activated in the discharge. Styrene was used for the plasma polymerization and molecular strucure and molecular weight distribution of the plasma -polymerized styrene were studies. The ploymer was evaluated to be an efficient electron beam resist. The sensitivity of the plasma-polymerized styrene film formed by this new reactor was better than that of the reported values of conventional polystyrene, Fine resist patterns could be successfully developed by a wet process.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.05a
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• pp.575-577
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• 1999

In this study, the PPPI(Plasma Polymerized Phenyl Isothiocyanate) resist thin film was manufactured in accordance with the plasma polymerization method and after exposing it to an electron beam, a pattern was formed by plasma etching. With the FT-IR(Fourier transform-infrared spectrometry) analysis, it was confirmed that the PI(Phenl Isothiocyanate) monomer was successsfully produced into a thin film by the plasma. The polymerization rate of the thin film was 450~ 1012($\AA$/min) to 100-200(W) discharge power and 120-12($\AA$/min) to 0.1 ~0.4[torr] system pressure.

• The korean journal of orthodontics
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• v.36 no.3 s.116
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• pp.198-206
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• 2006

With the introduction of the xenon plasma arc curing light and the LED curing light as orthodontic curing lights, the polymerizing time of orthodontic composites has clearly decreased. In contrast to various research cases regarding the polymerization time and bond strength of the xenon plasma arc curing light, not enough research exists on the LED curing light, including the appropriate polymerization time. The objective of this research was to compare the bond strength of the plasma curing light and the LED curing light in regards to the polymerization time. The polymerization time needed to achieve an appropriate adhesion strength of the bracket has also been studied. After applying orthodontic brackets using composite resin onto 120 human premolars, the plasma arc curing light and the LED curing light were used for polymerization for 4, 6, and 8 seconds accordingly. This research proved that the LED curing light provided appropriate bond strength for mounting orthodontic brackets even with short seconds of polymerization. The expensive cost and large size of the device limits the use of the plasma arc curing light, whereas the low cost and easy handling of the LED curing light may lead to greater use in orthodontics.

• Membrane Journal
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• v.20 no.4
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• pp.297-303
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• 2010

Composite membranes were prepared for membrane/cold condensation process for recovery of unreacted olefin monomer from the polyolefin polymerization process by solution coating and plasma polymerization processes. Poly(dimethylsiloxane) (PDMS) solution was coated on polysulfone (PSF) support and increase of prepolymer content in solution made more dense membrane structure to result in the increase of separation factor while absolute flux decreased. Permeation of organic materials through the composite membranes follows the sorption and diffusion mechanism, which brought about the results that separation factor increased with critical temperature of the organic materials, and that flux increased with the increase of the molar volume. Crosslinking period affected the permeation characteristics. Other types of composite membranes were fabricated by plasma polymerization of siloxane materials on polypropylene (PP) and PSF supports. PP was tested as a support for composite membranes, which had not been used so far in solution coating process, and plasma polymerization made the composite membranes equivalent performances to those of membranes prepared by solution coating process.

• Composites Research
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• v.26 no.3
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• pp.170-174
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• 2013

Atmospheric glow plasma polymerization was applied to wood powder before fabricating polypropylene (PP) matrix composites. Seven different types of monomers (Oxygen, Benzene, CH4, Acrylic-acid, Hexafluoroethane, Trifluorotolune, Hexamethyl-disiloxane) were analyzed to determine the most suitable precursor for plasma polymerization. The surface energy was calculated from measured contact angle about each monomer on PP. Hexamethyl-disiloxane (HMDSO) had a highest surface energy and is selected as the most suitable monomer. Wood powder and polypropylene were mixed as pellets by twin screw extruder and then 50 wt% wood powder/PP composites were produced by an injection machine. Tensile strength and Flexural strength have improved by 7.59% and 12.43% at the maximum respectively. SEM (Scanning Electron Microscope) observation on the fracture surface revealed that the plasma polymerization have improved the interfacial bonding and the mechanical properties of the composites.

• Korean Journal of Materials Research
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• v.33 no.4
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• pp.115-123
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• 2023

In this paper, we report and discuss the semi-permanently hydrophilic (SPH) treatment of polyester fabric using plasma polymerization and oxidation based on atmospheric pressure dielectric barrier discharge (APDBD) technology. SiO_xC_y(-H) was coated on polyester fabric using Hexamethylcyclotrisiloxane (HMCTSO) as a precursor, and then plasma oxidation was performed to change the upper layer of the thin film to SiO₂-like. The degradation of hydrophilicity of the SPH polyester fabrics was evaluated by water contact angle (WCA) and wicking time after repeated washing. The surface morphology of the coated yarns was observed with scanning electron microscopy, and the presence of the coating layer was confirmed by measuring the Si peak using energy dispersive x-ray spectroscopy. The WCA of the SPH polyester fabric increased to 50 degrees after 30 washes, but it was still hydrophilic compared to the untreated fabric. The decrease in hydrophilicity of the SPH fabric was due to peeling of the SiO_xC_y(-H) thin film coated on polyester yarns.

• Proceedings of the Korean Vacuum Society Conference
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• 1999.07a
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• pp.161-161
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• 1999

In the field of material science, the interests and efforts to modify the surface of materials in agreement with the need of usage have been extensively increasing. he modification to improve the wettability of surface is very important is terms of adhesion, printing, etc. It is very difficult to modify metal surface into hydrophilic one. therefore, surfactant coating has been generally used in many cases. However, surfactant has disadvantages such as environmental problem, soluble in water. in this study, hydrophilic polymer films as alternative of surfactant were deposited on metal substrate by DC plasma polymerization. Hydrophilic polymer films deposited by DC plasma show many merits such as good wettability, stone adhesion to substrate, high resistance to most chemicals. Monomer gas and reactive gas were used as source plasma polymerization. Plasma polymerized films were fabricated with process parameters of deposition time, ratio of gas mixture, current, pressure, etc. Effects of these variables on wettability of plasma polymer films will be discussed. With XPS and FT-IR analyses of plasma polymeric films, the relation between wettability and chemical state of polymer films by DC plasma was investigated.

• Proceedings of the KIEE Conference
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• 2002.07c
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• pp.1419-1421
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• 2002

Plasma polymerization of thiophene was carried out in a vacuum reactor with capacitively coupled electrode. This paper describes the dependence of molecular structure and electrical properties on the polymerization conditions such as plasma energy, mass flow rate and pressure. The plasma polymerized thiophene films were chracterized by FT-IR spectroscopy and SEM. The IR analysis revealed the thiophene rings are broken by the discharge energy.

• Korean Journal of Materials Research
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• v.15 no.8
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• pp.521-527
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• 2005

Surface modification of polypropylene hollow fiber membranes was peformed in order to develop blood-compatible biomaterials for use in the blood contacting and oxygenation membranes of a lung-assist device(LAD). Blood compatibility was determined by using anticoagulation blood and evaluating formation of blood clots on their surfaces as well as activation of plasma coagulation cascade, platelet adhesion, and aggregation. It was verified that the number of platelets on the silicone coated fibers was significantly lower than those on polypropylene. It was also found that the polypropylene hollow fiber membranes using plasma treatment exhibited suppression of complement activation in blood compatibility test.

• Journal of Integrative Natural Science
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• v.6 no.4
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• pp.211-214
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• 2013

In this study, in order to investigate how consecutive treatments of glass surface with HF acid and water vapor/Ar plasma affect the quality of 3-aminopropyltriethoxysilane self-assembled monolayer (APS-SAM), poly(3,4-ethylenedioxythiophene) (PEDOT) thin films were vapor phase-polymerized immediately after spin coating of FeCl3 and poly-urethane diol-mixed oxidant solution on the monolayer surfaces prepared at various treatment conditions. For the film characterization, various poweful tools were used, e.g., FE-SEM, an optical microscope, four point probe, and a contact angle analyzer. The characterization revealed that HF treatment is not desirable for the synthesis of a high quality PEDOT thin film via vapor phase polymerization method. Rather, sole treatment with plasma noticeably improved the quality of APS-SAM on glass surface. As a result, a highly dense and smooth PEDOT thin film was grown on uniform oxidant film-coated APS monolayer surface.