• Elastomers and Composites
• /
• v.55 no.2
• /
• pp.137-146
• /
• 2020

Part 1 provides a theoretical introduction of the hydrolysis mechanism, while Part 2 introduces other types of reaction mechanisms after hydrolysis in elastomer and PA66 composites. We reviewed the condensation reaction, which occurs after hydrolysis in bi-functional alkoxy silane (TESPD & TESPT), and investigated its effects on the mechanical properties of the composites. We also reviewed activators such as zinc soap, which enhances the mechanical properties of silica-silane-filled elastomer composites. The interaction parameter of silica-silane-filled elastomer composites [α_C (alpha C)] were also discussed. The effects of hydrolysis on the mechanical property changes in plastic composites were compared and reviewed.

• Proceedings of the Membrane Society of Korea Conference
• /
• 2004.05a
• /
• pp.170-174
• /
• 2004

Most of thin film composite reverse osmosis membranes include amide linkages, which are susceptible to chlorine attack resulting in N-chloro derivatives. This study examined a new method based on post-treatment of reverse osmosis membrane with various silane derivatives to improve chlorine resistance. The silane derivatives contain one alkyl group and three alkoxy groups such as trifluoromethyltrimethoxysilane, 3-aminopropylmethoxydiethoxysilane and 3, 3, 3-trifluoropropyltrimethoxysilane. Compared to commercial membranes, silane derivatives coated membranes showed significantly enhanced chlorine durability.

• Journal of the Korean Society of Propulsion Engineers
• /
• v.4 no.2
• /
• pp.1-5
• /
• 2000

The silane compounds as a coupling agent have been used in the propellant in order to enhance the mechanical property and lower the viscosity. They showed great effects in the PEG propellant. In PCP propellant, however, the silane compounds not only made a severe cure problem but also deteriorated the mechanical property. In this study, TESPN as a silane compound was applied in PEG and PCP binder for finding above factors. The main reason was that the main chains of PCP were broken due to the trans-esterification reaction of ester groups in PCP and alchol which was produced by reacting silane compounds and moisture in the solution of liquid binder.

• Macromolecular Research
• /
• v.13 no.5
• /
• pp.409-417
• /
• 2005

The surface of rutile titania nanoparticles was chemically modified by reacting with alkoxy silane. The surface and rheological properties in silicone oil having a wide range of viscosity were investigated. Total surface free energy($\gamma_S$) of the titania particles decreased from 53.12 to 26.94 mJ/$m^2$ as the silane used for surface treatment was increased from 0 to 5.0 wt$\%$. The surface free energy of neat silane was 25.5 mJ/$m^2$, which is quite close to that oftitania particles treated with 5.0 wt$\%$ silane. Due to the hydrophobic nature oftreated-titania, the contact angle was accordingly higher for polar solvent in the order of water>ethylene glycol> formamide>$\alpha$-bromonaphthalene. In sum of rheological behavior, as the applied shear stress or viscosity of the silicone oil increased, the titania particles tend to form layers and agglomerated clusters, showing shear-thinning and shear-thickening behaviors, sequentially. A good dispersion of discrete titania particles obeying a Newtonian flow behavior was achieved at a surface energy or low concentration of silane-treated titania particles in hydrophobic silicone oil.

• Applied Chemistry for Engineering
• /
• v.22 no.6
• /
• pp.691-696
• /
• 2011

Organic-inorganic hybrid coating solutions were prepared by using a sol-gel method for transparent film. In this study, colloidal silica (CS) and alkoxy silane such as vinyltrimethoxysilane (VTMS), and [3-(methacryloyloxy)]propyltri methoxy silane (MAPTMS) were used in various conditions such as types of organic silane, weight ratios of CS to silane and reaction times. Coating solutions which were bar coated on the PET (polyethyleneterephthalate) film and cured were investigated on the chemical and physical properties. The pencil hardness and adhesion of coating films were increased with increasing the organic silane content in the coating solution compared to that of PMMA (polymethamethylcrylate) coating solution.

• Applied Chemistry for Engineering
• /
• v.25 no.4
• /
• pp.352-356
• /
• 2014

PDMS modified epoxy resin with epoxy group (EMPDMS) was prepared from the reaction of ${\alpha},{\omega}$-aminopropylpolydimethylsiloxane and diglycidyl ether of bisphenol-A (DGEBA) based epoxy resin, and PDMS modified epoxy hybrid compound (EMPDMSH) was prepared by introducing alkylesteraminopropyl alkoxy silane to EMPDMS. Their structures were characterized using FT-IR, $^1H$-NMR and $^{29}Si$-NMR. Coating materials were prepared by mixing EMPDMSH base and solvent. Physical properties of the coating materials coated on epoxy/glass fiber composite film were measured according to the content of PDMS in EMPDMSH. Contact angle of coating film was increased 30 to 71 degree. Adhesive property of coating film was 5B degree better then epoxy or acrylate coating materials, and surface roughness was decreased as increasing in EMPDMSH.

• Membrane Journal
• /
• v.17 no.1
• /
• pp.44-53
• /
• 2007

The primary objective of this study is to increase the extent of water flux and fouling resistance of nano-filtration or reverse osmosis membranes. This study was performed to investigate the effect of surface characteristics of silane coated membranes on modified fouling index. Commercial polyamide composite RO membrane (RE1812-LP) and NF membrane (ESNA4040-LF) were treated with silane coupling agents in ethanol at five different concentrations. The silane coupling reagent, aminopropylmethoxydiethoxysilane, contains one aminoalkyl and three alkoxy groups. The hydrophilic effect of aminoalkyl group of APMDES on the permeability and fouling resistance of the modified membrane was examined. The surfaces of the modified membranes were characterized by FE-SEM, contact angle analyzer, and zeta potentiometer in order to confirm successful sol-gel methods. The modified NF membranes showed significantly enhanced water flux and fouling resistance without a decrease in salt rejection in divalent ionic feed solution.

• Polymer(Korea)
• /
• v.29 no.3
• /
• pp.242-247
• /
• 2005

Two kinds of colloidal silica(CS)/silane sol solutions were prepared in variation with synthesizing parameters such as kinds of CS, ratio of CS to silane and reaction time. Such sol solutions were obtained from 1034A Cs/methyl-trimethoxysilane(MTMS) and HSA CS/MTMS solutions. In the case of 1034A CS/MTMS CS/silane sol, coating film had high contact angle and more enhanced flat surface than those in the case of HSA CS/MTMS sol. In the case of thermal stability, thermal dissociation of 1034A CS/MTMS sol did not occur up to $550^{circ}$. The thickness of coating film obtained from 1034A CS/MTMS sol increased with increasing the amount of MTMS. The hardness of coating films obtained from 1034A CS/MTMS sol decreased with increasing the amount of MTMS. Surface free energy of CS/silane sol-gel coating film decreased with increasing amount of MTMS.

• Journal of Conservation Science
• /
• v.26 no.3
• /
• pp.325-334
• /
• 2010

In order to clarify the effect of consolidant, the artificial porous material with low intensity was manufactured using granite powder and Portland cement. We have prepared four kinds of alkoxysilane system consolidants, a acrylic resin and a epoxy resin and investigated about characteristics before and after consolidation. As a result of the research, Silres BS OH 100 was effective for density and surface hardness. SS-101 with hydrophobicity and Site SX-RO with hydrophilicity had the good durability over salts weathering. On the other hand, Syton HT-50 and Paraloid B72 were easily destructed by salt weathering because they were concentrated on surface area by the low penetration depth. Araldite 2020 was the most effective consolidant for improvement of physical properties.