• Journal of the Korean Applied Science and Technology
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• v.25 no.1
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• pp.1-14
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• 2008

To prepare weather-resistant modified silane acrylic resin coatings for an architectural purpose, tetrapolymers were synthesized by radical polymerization. 3-Methacryloxypropyltrimethoxysilane (MPTS) as a silicone monomer and n-butyl acrylate, methyl methacrylate, and n-butyl methacrylate as acrylic monomers were used. The composition of monomers was adjusted to fix the glass transition temperature of acrylic polymer for $20^{\circ}C$. The composition of MPTS in the synthesized polymer were varied from 10 wt% to 30 wt%. On the basis of synthesized resin amber paints were prepared and their physical properties and effects on weatherability were examined. The presence of MPTS in modified silane acrylic resins generally resulted in low molecular weight and broad molecular weight distribution, and also lowered the viscosity of the copolymers. The coated films prepared from these resins showed good and balanced properties in general. Adhesion to the substrate was outstanding in particular. Weatherability tests were carried out in three different types such as outdoor exposure, QUV, and SWO. The test results showed that the modified silane acrylic resins containing 30 wt% of MPTS had superior weathering properties.

• Polymer(Korea)
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• v.31 no.1
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• pp.86-91
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• 2007

Polydimethylsiloxane branched HEMA (SH) was Prepared by reacting polydimethylsilorane prepolymer and 2-hydroxyethyl methacrylate (HEMA). Polyacrylate modified Polyorganosiloxane (SMPA) was prepared by polymerization of methacrylic acid(MA), allyl glycidyl ether(AGE), aminopro- pyltrimethoxysilane (APTS), and SH. Their structures were confirmed by the measurement of FTIR and $^1H-NMR$ and thermal properties of SMPA were studied from TGA. Residual weight of SMPA at $400^{\circ}C$ increased according to increasing content of the APTS to 63 from 55%. SMPA sealant was prepared by adding additives, such as viscosity increasing agent, crosslinking agent, and fillers. Adhesion characteristics of SMPA-3 sealant was determined to be maximum load elongation, 2.01 %, and break load elongation, 2.28%. Adhesion characteristics for SMPA sealant prepared from SMPA-3 were better than those for SMPA sealant prepared from SMPA-1 and SMPA-2.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.12
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• pp.7561-7568
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• 2013

Galectin-3 (Gal-3) is a carbohydrate-binding protein which is thought to be involved in cancer progression but its contribution to epithelial ovarian cancer (EOC) remains unclear. The present study sought to determine the role of Gal-3 in chemoresistance of the human SKOV-3 ovarian cancer cell line to paclitaxel (PTX) using recombinant human Gal-3 (rhGal-3) and PectaSol-C modified citrus pectin (Pect-MCP) as a specific Gal-3 competitive inhibitor. Our results showed 41% increased cell proliferation, 36% decreased caspase-3 activity and 33.6% increased substrate-dependent adhesion in the presence of rhGal-3 compared to the control case (p<0.001). Treatment of cells with a non-effective dose of PTX (100nM) and 0.1% Pect-MCP in combination revealed synergistic cytotoxic effects with 75% reduced cell viability and subsequent 3.9-fold increase in caspase-3 activity. Moreover, there was 39% decrease in substrate-dependent adhesion compared to control (p<0.001). These results suggest that inhibition of Gal-3 could be a useful therapeutic tool for combination therapy of ovarian cancer.

• Journal of Adhesion and Interface
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• v.3 no.3
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• pp.15-21
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• 2002

The modified polyethylene(m-PE) films were prepared from aqueous dispersions which were synthesized by reacting poly(ethylene-co-methylacrylate) with aqueous KOH and ammonia solution to attach -COOK, $CONH_2$, and COOH as pendent groups in the polyethylene backbones. Thermal, tensile and heat-seal properties were measured to investigate the effect of the pendent groups. Endothermic peaks on DSC curves were affected by the thermal history of the samples and a melting peak was observed at around $86^{\circ}C$ on the second heating curve while three melting peaks were shown on the first heating curve. A minimum value of tensile strength was shown at 70 mole% of COOK based on pendent groups. Tensile modulus increased with increasing the amide content in pendent groups. The m-PE films were heat-sealed at lower temperature than LDPE films and showed a minimum heat seal strength at around 70 mole% COOK content in pendent groups.

• Journal of Adhesion and Interface
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• v.3 no.3
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• pp.7-14
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• 2002

Modified polyethylenes with polar side groups of -COOK, $-CONH_2$, and -COOH were prepared at a dispersion state in water by reacting poly(ethylene-co-methylacrylate) (PEMA) with aqueous solution of KOH and ammonia. Types and their contents of side groups were investigated by infrared spectroscopy, elemental analysis and atomic absorption analysis. Solution viscosity and surface tension were also measured as a function of solid contents. Stability and transparency of the dispersions were greatly affected by the content of COOK in the side groups. The stable dispersion could be prepared at a composition of COOK of 20 mole% at least. The transparency was increased with increasing the COOK contents, but decreased with increasing the amide content at a constant composition of COOK. Solution viscosities increased abruptly at a lower solid content when the COOK contents were increased, implying higher entanglement between the chains in dispersions with higher content of hydrophilic COOK group. The dispersions of higher COOK content revealed lower surface tension values.

• Journal of the Korean Applied Science and Technology
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• v.33 no.1
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• pp.168-175
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• 2016

The surface of glass fiber bundle was modified with functionalized silanes and phenolic resin to improve the tensile strength as well as the adhesion of glass fiber to matrix phenolic resin. The surface modification of reinforcing glass fiber can play a significant role in controlling whole composite characteristics. We applied surface modification of glass fiber with two different functionalized silanes, such as glycidyltrimethoxysilane(G-silane) and aminopropyltriethoxysilane (A-silane), and phenol formaldehyde(PF) resin in one pot or separated process under different coating compositions and temperatures. Thermal treatment temperature is very important factor to improve the mechanical properties of modified glass fiber. Modified glass fiber bundle treated at $170^{\circ}C$ showed the highest tensile strength of $10.05g_f/D$. Surface analyses by scanning electron microscope(SEM) and FT-IR spectroscopy were used to characterize the surface coatings on glass fiber bundles. Mechanical property changes as functions of treatment conditions and coupling agent types were also explained.

• Journal of the Korea Institute of Building Construction
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• v.20 no.1
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• pp.35-41
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• 2020

The thin coating material used in the outer insulation finishing method is a finishing material mainly based on acrylic emulsion. In this study, the properties of silane modified acrylic emulsion and silica dispersed acrylic emulsion were evaluated. Experimental results showed that the silane modified acrylic emulsion had no significant effect on improving tensile strength, but was effective in improving the performance of adhesion strength, water absorption coefficient, and hot and cold repeat resistance. Silica-dispersed acrylic emulsions were effective in improving tensile strength, and at 10% substitution rate, they were effective in improving the performance of adhesion strength, water absorption coefficient and hot / cold resistance. Through this, it was judged that a composite emulsion capable of improving the performance of the acrylic emulsion could be prepared.

• Elastomers and Composites
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• v.39 no.4
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• pp.301-308
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• 2004

Three types of parylene (PA-N, PA-C, PA-D) were used for coating the surface on natural latex rubbers in order to improve surface characteristics including mechanical properties and biocompatibility. The parylene coating was the CVD (chemical vapor deposition) method, and the surface properties of the modified latex were measured. Annealing effects on the mechanical properties of the coated latex were also investigated. The adhesion between latex and parylene was good for all the types of parylene used. As annealing temperature was increased, latex modified with PA-N became more hydrophobic, while the latex treated with PA-C and PA-D became more hydrophilic. As the annealing temperature was raised, the tensile strength was increased, and the elongation was decreased. The biocompatibility was noticeably improved on the latex surface modified with the parylenes through CVD method.

• Journal of Biomedical Engineering Research
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• v.17 no.3
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• pp.355-364
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• 1996

Construction of the stable monolayer of endothelial cells onto physicochemically modified polymeric surFace is one of the appropriate method to develop the small caliber vascular graft with the long-term patency. In this study, we constructed the monolayer of endothelial cells on the fibronectin rind the extracellular matrix-coated polyurethane surface derived from human fibroblast cells. To elucidate the adhesion strength of endothelial cells on the extracellular matrix-coated polyurethane, a laminar flow chamber apparatus was developed to exposure the shear stress on the apical membrane of ondothelial cells. Endothelial cells show the strongest adhesion after two days of seeding onto the fibronectin-coated polyurethane surface, whereas endothelial cells on the extracellular matrix derived from the human flbroblast cells show the minimal doubling time of cellular growth.

• Journal of Adhesion and Interface
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• v.6 no.4
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• pp.7-11
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• 2005

Multi-walled carbon nanotubes (CNTs), which were purified by etching in 25% $H_2SO_4/HNO_3$ solution at $60^{\circ}C$ for 2 h, were modified via plasma polymerization coating of acrylic acid, allylamine or acetylene, and then utilized to prepare PEI/CNT composites. First, plasma polymerization conditions were optimized by measuring the solvent resistance of coatings in THF, chloroform and NMP, and the tensile strength of PEI/CNT (0.5%) composites as a function of plasma power (20~50 W) and monomer pressure (20~50 mTorr). The tensile strength of PEI/CNT composites was further evaluated as a function of CNT loading (0.2, 0.5 and 1%). Finally, FT-IR was utilized to provide a better understanding of the improved tensile properties of PEI/CNT composites via plasma polymerization coating of CNTs. Plasma polymerization of acrylic acid greatly enhanced the tensile strength of PEI/CNT composites, as did allylamine but to a lesser degree, while acetylene plasma polymerization coating decreased tensile strength.