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

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.29 no.12
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• pp.621-627
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• 2017

Nitrogen ion with various levels of dose and irradiation energy was irradiated on aluminum surfaces. Contact angle of surface was increased and surface color was changed by nitrogen ion implantation. During steam condensation experiment using nitrogen ion implanted specimen, dropwise condensation initially occurred on specimens. However, condensation mode eventually changed into filmwise condensation. The color of the surface was also changed from yellow-brown to silver-white. This change of surface color and condensation mode were results of hydrolysis reaction between condensate and nitrogen ion implanted on aluminum surfaces.

• Analytical Science and Technology
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• v.12 no.6
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• pp.509-514
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• 1999

The systematic modification of titanium(IV) isopropoxide with acetic acid as a organic additive was done and identifided by FT-IR, $^1H$, $^{13}C$ NMR and UV-Vis spectroscopy. The structure was cbanged after hydrolysis-condensation reaction and drying process. The hydrolysis-condensation rates of modified Ti alkoxide with acetic acid were investigated by $^1H$ NMR spectroscopy. This modified Ti(IV) alkoxide was less reactive toward hydrolysis-condensation reaction than $Ti(OPr^i)_4$, which can be attributed to the stable ligand structure between Ti alkoxide and ligand. The structural change on obtained from gel powders with heat treatment was also observed by FT-IR spectroscopy.

• YAKHAK HOEJI
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• v.35 no.5
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• pp.389-393
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• 1991

A convenient method for the synthesis of indobufen, which is a potent antiinflammatory agent, was described. Ethyl 2-phenylbutyrate(4) was prepared by Friedel-Crafts reaction of benzene with ethyl $\alpha$-chloro-$\alpha$-(methylthio)acetate(l) followed by ethylation and desulfurization of the resultant ethyl 2-(methylthio)phenylacetate(2). Ethyl 2-(p-aminophenyl)butyrate(6) was prepared by nitration of (4) and successive reduction of ethyl 2-(p-nitrophenyl) butyrate(5). Indobufen was obtained by condensation reaction of (6) with phthalic anhydride followed by reduction and hydrolysis of the resultant ethyl 2-[p-(1, 3-dioxo-2-isoindolinyl)phenyl]butyrate(7).

• Bulletin of the Korean Chemical Society
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• v.20 no.12
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• pp.1394-1398
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• 1999

The structures of modified Ti$(OPr^i)_4$ with chelating ligands (L) such as ethylacetoacetate (Etac), acetylacetone (Acac) and methylacetoacetate (Mtac) were identified by using IR, ¹H NMR and $^13C$ NMR spectroscopies, and the octahedral structure was confirmed after modification. The pre-edge peaks of XANES spectra of modified metal alkoxides also denoted the mixture of five-fold and six-fold structures. The EXAFS fitting results showed the local structure around Ti atom after alkoxide modification. The hydrolysis-condensation rates of modified Ti alkoxide with organic additives were investigated by ¹H NMR spectroscopy. The Ti$(OPr^i)_4$ modified by Acac was less reactive toward hydrolysis-condensation reaction than those modified by the other alkoxides, which can be attributed to the stable ligand structure between Ti$(OPr^i)_4$ and Acac. The small particle size of modified Ti$(OPr^i)_4$ sol was obtained when Acac was employed.

• Journal of the Korean Ceramic Society
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• v.28 no.11
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• pp.865-872
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• 1991

LAS (lithium aluminosilicate) sol was synthesized using the hydrolysis-condensation reaction of TEOS, chelated Al(OBus)3 and LiNO3 with H2O in alcohol (ethanol+2-propanol) medium. Lowering Li content by a factor of 1/2 significantly enhanced densification and retarded the crystallization of LAS gel by ~30$0^{\circ}C$. Dense LAS specimen with essentially pore-free microstructure was obtained by sintering the sol-gel derived gel at 80$0^{\circ}C$ for 4 h and annealing at 120$0^{\circ}C$ for 2 h. Similary, a mixed colloidal processing was attempted as a convenient, alternative route for the fabrication of dense LAS sintered body. The $\beta$-spodumene seeding (~0.8 ${\mu}{\textrm}{m}$) in the sol-gel derived LAS modified the sequence of phase transformations and lowered the temperature of crystallization by ~12$0^{\circ}C$. Combining the epitaxial seeding with the sol-gel process, we could lower the crystallization temperature to the sintering temperature range (~80$0^{\circ}C$) and, demonstrate a possibility of making the viscous sintering/crystallization as a continuous as a continuous unit process.

• Polymer(Korea)
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• v.35 no.4
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• pp.302-307
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• 2011

The parameters of silanol formation reaction of organosilane including solvent type, solution concentration, pH and hydrolysis time influence the adhesion property of 2 layer flexible copper clad laminate (FCCL). Especially, the hydrolysis reaction time of silane coupling agent affects the formation of the silanol groups and their self-condensation to generate oilgomeric structure to enhance the surface treatment as an adhesive promoter. In our study, we prepared the binary silane coupling agents to control hydrolysis reaction rate and surface energy after treatment of silane coupling agents for increasing the adhesive property between a copper layer and a polyimide layer. The surface morphology of rolled copper foil, as a function of the contents of the coated binary silane coupling agent, was fully characterized. As fabricated 2-layer FCCL, we observed that adhesive properties were changed by hydrolysis rate and surface energy.

• Journal of the Korean Ceramic Society
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• v.32 no.7
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• pp.783-792
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• 1995

Sol-Gel derived ferroelectric PZT thin films were fabricated on ITO/Glass and Si/SiO2 substrates. In order to investigate the effect of catalysts on the densification and crystallization of PZT thin films, a nitric acid or ammonium hydroxide was added to the PZT stock solution at the state of partial hydrolysis reaction. The measured pH for a stable PZT sol was 5.2~9.3. In case of an acid-catalyzed PZT sol, a highly condensed particulate PZT sol was formed by accelerating the hydrolysis reaction. But weakly branched polymeric PZT sol was formed with a base-catalyzed condition. The difference in densification behavior was not found in the pH range of added catalyst, but the refractive index of PZT thin film was increased rapidly as the annealing temperature increased. The PZT thin film annealed at 54$0^{\circ}C$ for 10 min was fully densified and its refractive index was above 2.4. When the annealing temperature increased, the transition from the pyrochlore phase to perovskite appeared at 54$0^{\circ}C$. The base-catalyzed PZT thin film suppressed to form the pyrochlore phase and proceeded effectively to convert the perovskite phase. This was due to the formation of polymeric molecular structure by controlling the hydrolysis and condensation reaction through the additiion of the ammonium hydroxide.

• YAKHAK HOEJI
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• v.35 no.4
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• pp.314-318
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• 1991

A convenient method for the synthesis of indoprofen, which is a potent antiinflammatory agent, w described. Ethyl $\alpha$-(4-aminophenyl)propionate was prepared by nitration of ethyl $\alpha$-phenylpropionate, followed by reduction. Ethyl $\alpha$-[4-(1, 3-dioxo-2-iso-indolinyl)phenyl]propionate was obtained from condensation reaction of phthatic anhydride and ethyl $\alpha$-(4-aminophenyl)propionate. Indoprofen was prepared by reduction of ethyl $\alpha$-[3-(1, 3-dioxo-2-iso-indolinyl)phenyl]propionate with zinc dust-acetic acid, followed by hydrolysis of the resultant ethyl $\alpha$-[4-(1-oxo-2-iso-indolinyl)pheriyl]propionate.

• Korean Journal of Materials Research
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• v.22 no.6
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• pp.298-302
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• 2012

Fe/$SiO_2$ core-shell type composite nanoparticles have been synthesized using a reverse micelle process combined with metal alkoxide hydrolysis and condensation. Nano-sized $SiO_2$ composite particles with a core-shell structure were prepared by arrested precipitation of Fe clusters in reverse micelles, followed by hydrolysis and condensation of organometallic precursors in micro-emulsion matrices. Microstructural and chemical analyses of Fe/$SiO_2$ core-shell type composite nanoparticles were carried out by TEM and EDS. The size of the particles and the thickness of the coating could be controlled by manipulating the relative rates of the hydrolysis and condensation reaction of TEOS within the micro-emulsion. The water/surfactant molar ratio influenced the Fe particle distribution of the core-shell composite particles, and the distribution of Fe particles was broadened as R increased. The particle size of Fe increased linearly with increasing $FeNO_3$ solution concentration. The average size of the cluster was found to depend on the micelle size, the nature of the solvent, and the concentration of the reagent. The average size of synthesized Fe/$SiO_2$ core-shell type composite nanoparticles was in a range of 10-30 nm and Fe particles were 1.5-7 nm in size. The effects of synthesis parameters, such as the molar ratio of water to TEOS and the molar ratio of water to surfactant, are discussed.