• Polymer(Korea)
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• v.29 no.1
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• pp.102-105
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• 2005

Photoinitiated polymeric dental restorative nanocomposites (PDRNC) were designed to be useful for the variety of dental restoration. Hybrid-filler composed of barium silicate (avg. dia.:1 ${\mu}m$) and nano-sized silica (avg. dia: 40 and 7 nm) was adopted as a filler system. To improve the interfacial behavior with the resin matrix of bisphenol A glycerolate methacrylate/triethyleneglycol dimethacrylate (60/40 wt%), the surface of the filler was hydrophobically treated with a silane coupling agent. A visible light system of camphorquinone photo-initiator and 2-(dimethylamino)ethyl methacrylate photo-accelerator was utilized to activate the PDRNC. Esthetic properties of PDRNC was investigated by measuring the Hunter L, a, b values and it was discovered that PDRNC produced in this work showed excellent esthetic properties with an increase in 7 nm nanofiller content.

• Journal of Adhesion and Interface
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• v.19 no.4
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• pp.163-166
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• 2018

Dip-pen nanolithography(DPN) is an atomic force microscope (AFM) based method of generating nano- or micro-patterns. This technique has been used to transfer various ink materials on the substrate through water meniscus formed between AFM tip and the substrate surface. In this study, the heptadecafluoro-1,1,2,2-tetrahydrodecyltrimethoxysilane (HDFDTMS) ink materials were coated on the pre-coated AFM tip surface with the HDFDTMS molecules. When the tip brought into contact with the hydroxyl-functionalized silicon surface, HDFDTMS ink molecules have been successfully transported from the tip onto the surface via water meniscus. The created array and passivation area showed stable structures on the surface, and the transport of ink materials from the AFM tip to the surface followed linear increase in pattern size with contact time.

• Polymer(Korea)
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• v.28 no.1
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• pp.3-9
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• 2004

Silane modified perfluoropolyethers (SPFPE) was synthesized as a self-assembled mono-layers (SAMs) thin film for micro-electro mechanical system (MEMS). SPFPE was compared to the Perfluoropolyethers (PFPE) as well as octadecyltrichlorosilane (OTS) and perfluorooctyltrichlorosilane (FOTS) with respect to the development of hydrophobicity in the SAMs surface. SPFPE shows less hydrophobicity than those of OTS and FOTS. Thermal annealing of SPFPE SAMs resulted in the enhancement of hydrophobicity as much as those of OTS and FOTS. The SAMs formed from SPFPE were found to be similar as OTS and FOTS SAMs with smooth R$\sub$a/ values of 0.3 nm. However, the flexible chain mobility of SPFPE resulted in 50% reduction as much as the fiction force in OTS.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2000.04a
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• pp.159-162
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• 2000

Interfacial and microfailure properties of carbon fiber/epoxy matrix composites were evaluated using both tensile fragmentation and compressive Broutman tests with acoustic emission (AE). Amino-silane and maleic anhydride polymeric coupling agents were used via the dipping and electrodeposition (ED), respectively. Both coupling agents exhibited higher improvements in interfacial shear strength (IFSS) under tensile tests than compressive cases. However, ED treatment showed higher IFSS improvement than dipping case under both tensile and compressive test. The typical microfailure modes including fiber break, matrix cracking, and interlayer failure were observed during tensile test, whereas the diagonal slippage in fiber ends was observed during compressive test. For both the untreated and treated cases AE distributions were separated well under tensile testing. On the other hand, AE distributions were rather closer under compressive tests because of the difference in failure energies between tensile and compressive loading. Under both loading conditions, fiber breaks occurred around just before and after yielding point. Maximum AE voltage fur the waveform of carbon or basalt fiber breakage under tensile tests exhibited much larger than those under compressive tests.

• Journal of Environmental Science International
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• v.14 no.1
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• pp.97-103
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• 2005

Because of the toxicity of hexavelant chromium ion, treatments of metallic surface with chromate compounds to retard corrosion are undesirable for safety control in industrial uses and protection of environment. In this study, we investigated several compounds such as inorganic, organic, and polymer materials in order to sub­stitute the chromate conversion treatment on steel sheet. The corrosion property was investigated in a salt spray tester with 3.5 $wt.{\%}\;NaCI\;at\;35^{\circ}C.$ The results showed that the zirconium/silane/polymer triple coatings on the galvanized steel exhibited a significant retardation of corrosion. Although the multicoating system needs a com­plexed processing, we can confirm a possibility of development of a chromate-free chemical conversion treat­ment for galvanized steel sheet.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2004.05a
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• pp.33-37
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• 2004

Recently, Growing tendency for structure surface to use water repellent agent has increased steadily. But investigation of it's protection and durability property is not sufficient. Therefore, this paper shows the investigation about repellent property and micro structure's change in surface layer of mortar that is applied by water repellent agent. Water repellent property, absorption coefficient, air permeability, porosity and observation of micro construct was investigated according to water repellent agent type. The test results indicated that mortar applied water repellent agent appears tiny absorption coefficient, but air permeability is maintained. The reason is because silane solution is coating at capillary surface of a wall and minute pore structure is changeless.

• Journal of Industrial Technology
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• v.20 no.A
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• pp.179-184
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• 2000

The surface of porous alumina membrane was modified with silane coupling agent in order to enhance hydrophobicity. The contact angle of water to the surface-modified alumina membrane was greater than $90^{\circ}$. The surface-modified membrane was tested in vapor permeation for the concentration of aqueous ethanol. With the increase of ethanol concentration in the feed, permeation flux increased due to the greater affinity of ethanol with surface-modified alumina membrane than that of water. The experimental results showed that the permeation rate of surface-modified alumina membrane was 15~1000 times greater than that of polymer membranes.

• Macromolecular Research
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• v.17 no.4
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• pp.227-231
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• 2009

New polyelectrolytes derived from poly(amide-sulfone)s and 1,5-dibromopentane were simultaneously fabricated on the electrode by the crosslinking reaction. The substrate was pretreated with a bromoalkyl-containing, silane-coupling agent to anchor the humidity-sensitive membrane to the substrate through the covalent bond. When the resistance dependence on the relative humidity of the crosslinked poly(amide-sulfone)s was measured, the resistance varied by three orders of magnitude between 20%RH and 90%RH, which was the required RH range for a humidity sensor operating at ambient humidity. Their water durability, long-term stabilities under various environments, hysteresis and response and recovery times were measured and evaluated as a humidity-sensing membrane.

• Textile Coloration and Finishing
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• v.20 no.4
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• pp.1-7
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• 2008

Methacryloxypropyl trimethoxysilane (MAPTMS), a hybrid organic-inorganic monomer, was photografted onto PET fabric using benzophenone (BP) as a photoinitiator. It was found that a UV energy of 43.2J/$cm^2$ was required to optimally photograft the MAPTMS onto PET fabrics which was applied with an aqueous formulation of 10% MAPTMS, 20% BP and 0.5% N-Methyldiethanol amine (MDEA). The MDEA additive was efficient in reducing atmospheric oxygen inhibition of polymer radicals which eliminated compulsory nitrogen inerting. The surface grafting of PET fabrics was verified by fourier transform infrared spectroscopy (FT-IR) and scanning electron spectroscopy (SEM). The grafted PET fabrics with the hybrid monomer showed higher thermal stability due to the introduced silane component in the monomer as ascertained by higher char content at 800$^{\circ}C$, which increased to 14.5% for the 15.8% grafting compared to 8.2% for the untreated.

• Journal of Integrative Natural Science
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• v.2 no.2
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• pp.78-81
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• 2009

In recent years, organometallic polymer containing silane and silole unit has been a topic of interest because of the wide range of optical, electrical and luminescent properties. In previous work, we synthesized functionalsilanebridged[1]ferrocenophane from the reaction of dimethyldichlorosilane[Me2SiCl2] and diphenyldichlorosilane[Ph2SiCl2] and dichloromethylvinylsilane[C3H6SiCl2] with ferrocene$[Fe({\eta}-C5H4)2]$ and n-BuLi. In this work, we have synthesized Poly(ferrocenylsilane) via the Thermal Ring-Opening Polymerization(ROP). characteristics of the poly(ferrocenylsilane) were investigated by gel permeation chromatography(GPC), 1H- and 13C-NMR spectroscopy.