• Journal of the Korea Organic Resources Recycling Association
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• v.13 no.3
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• pp.97-104
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• 2005

In this study, the change of water content, pH, and combustion weight on the decomposition of poly ester vinyl and high density poly ethylene were examined. The poly ester vinyl was degraded by microorganism in food wastes for 30 days, while high density poly ethylene vinyl was not degraded. Also, the poly ester vinyl was rapidly degraded after the 10 days of operation and its weight was decreased. In the combustion reaction between $300^{\circ}C$ and $600^{\circ}C$, complete combustion was performed. Due to the degradation of poly ester vinyl by microorganism in food waste, the pH was increased from 4.26 to 7.6. During of 60 days operation, poly ester vinyl was degraded over 90%.

• Journal of the Korean Applied Science and Technology
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• v.6 no.1
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• pp.51-57
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• 1989

A series of four sodium ${\alpha}-sulfo$ fatty vinyl ester oligomers including sodium ${\alpha}-sulfo$ lauric acid vinyl ester oligomer, sodium ${\alpha}-sulfo$ myristic acid vinyl ester oligomer, sodium ${\alpha}-sulfo$ palmitic acid vinyl ester oligomer and sodium ${\alpha}-sulfo$ stearic acid vinyl ester oligomer were examined for surface activities such as surface tension, foaming power, foam stability, emulsifying power, dispersion effect, solubilization of orange OT. The critical micelle concentration(CMC) was also evaluated. Consequently, these sodium ${\alpha}-sulfo$ fatty acid vinyl ester oligomers were shown to have a good cohesive power and dispersion effect.

• Journal of the Korean Applied Science and Technology
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• v.6 no.1
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• pp.21-26
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• 1989

Four fatty acid vinyl esters were synthesized by transesterification between vinyl acetate and lauric acid, myristic acid, palmitic acid, stearic acid, respectively. Fatty acid vinyl ester oligomers were prepared from polymerization of four fatty acid vinyl esters in the presence of potassium persulfate in methanol. The ${\alpha}-sulfonation$ of these four fatty acid vinyl ester oligomer were carried by direct addition of sulfur trioxide. Especially, molecular weights of sodium ${\alpha}-sulfo$ fatty acid vinyl ester oligomers were measured by boiling point method.

• Composites Research
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• v.27 no.1
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• pp.19-24
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• 2014

In this study, an investigation on mechanical properties of flax/vinyl ester natural fiber composite was performed as a precedent study on the design of eco-friendly structure using flax/vinyl ester composite. Vacuum Assisted Resin Transfer Molding(VARTM) manufacturing method was adopted for manufacturing the flax fiber composite specimen. The mechanical properties of the manufactured flax composites were compared with flax composite data cited from some references. Based on this, the experimental data showed that the flax/vinyl ester composite has some advantages when it is applied to environment-friendly structure.

• Proceedings of the Korean Fiber Society Conference
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• 1998.04a
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• pp.130-134
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• 1998

The physical properties of poly(vinyl alcohol) (PVA) are highly dependent on the degree of syndiotacticity, which is determined primarily by the choice of the vinyl ester monomer precursor. Efforts to produce more syndiotactic PVAs, as well to increase the molecular weight, have centered on the polymerization of vinyl trifluoroacetate,$^1$ vinyl trichloroacetate,$^2$ and vinyl pivalate (VPi).(omitted)

• Journal of the Korean Applied Science and Technology
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• v.15 no.3
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• pp.55-60
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• 1998

The sodium ${\alpha}-sulfo$ fatty acid vinyl ester oligomers, which are oligomer type surfactants were prepared by polymerization with fatty acid vinyl acetate. The ${\alpha}-sulfonation$ of fatty acid vinyl ester oligomers were carried by direct addition of sulfur trioxide. The dispersing performance of oligomer type anionic surfactants and sodium dodecyl sulfate(SDS) in the aqueous suspension of iron oxide and titanium dioxide particles was evaluated by particle size distribution and zeta-potential measurement. As results, the particles of iron oxide and titanium dioxide were flocculated by addition of small amount of oligomer type anionic surfactants and sodium dodecyl sulfate(SDS), then the flocks redispersed by more addition of oligomer type anionic surfactants and SDS. The flocculation, redispersion process was observed in lower concentration range of oligomer type anionic surfactants than SDS. Especially, the dispersing action of sodium ${\alpha}-sulfo$ palmitic acid vinyl ester oligomer was better than sodium ${\alpha}-sulfo$ lauric acid vinyl ester oligomer.

• Composites Research
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• v.30 no.5
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• pp.303-309
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• 2017

Organo-montmorillonite (OMMT) has attracted much attention for fiber-reinforced polymer composites as a filler material due to high aspect ratio and low charge density. The present study focused on the fabrication of nanocomposites using Vinyl ester and Jute fabric as matrix and reinforcement respectively. The OMMT was uniformly dispersed in vinyl ester resin at 1, 2 and 3 wt%, loading through high speed mechanical stirrer at room temperature and further nanocomposites were manufactured through vacuum assisted resin infusion (VARI) technique. Effects of OMMT on the mechanical properties of vinyl ester/Jute composites were carefully investigated through tensile, bending and Izod impact tests, which revealed significant improvement in mechanical properties. The morphology of the nanocomposites after tensile test was investigated by SEM which affirmed that OMMT filled nanocomposites has improved interactions with the host matrix than the pure composites. Based on the nature and flame retardancy mechanism, the OMMT slightly improved the flammability property which was clearly explained by horizontal burning test.

• Advances in nano research
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• v.13 no.1
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• pp.97-111
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• 2022

In the present article, silica nanoparticles (SNPs) were exploited to improve the tribological and mechanical properties of vinyl ester/glass fiber composites. To the best of our knowledge, there hasn't been any prior study on the wear properties of glass fiber reinforced vinyl ester SiO₂ nanocomposites. The wear resistance is a critical concern in many industries which needs to be managed effectively to reduce high costs. To examine the influence of SNPs on the mechanical properties, seven different weight percentages of vinyl ester/nano-silica composites were initially fabricated. Afterward, based on the tensile testing results of the silica nanocomposites, four wt% of SNPs were selected to fabricate a ternary composite composed of vinyl ester/glass fiber/nano-silica using vacuum-assisted resin transfer molding. At the next stage, the tensile, three-point flexural, Charpy impact, and pin-on-disk wear tests were performed on the ternary composites. The fractured surfaces were analyzed by scanning electron microscopy (SEM) images after conducting previous tests. The most important and interesting result of this study was the development of a nanocomposite that exhibited a 52.2% decrease in the mean coefficient of friction (COF) by augmenting the SNPs, which is beneficial for the fabrication/repair of composite/steel energy pipelines as well as hydraulic and pneumatic pipe systems conveying abrasive materials. Moreover, the weight loss due to wearing the ternary composite containing one wt% of SNPs was significantly reduced by 70%. Such enhanced property of the fabricated nanocomposite may also be an important design factor for marine structures, bridges, and transportation of wind turbine blades.

• Polymer(Korea)
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• v.32 no.2
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• pp.95-102
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• 2008

The $\alpha$,$omega$-diacrylate poly(dimethylsiloxane) (DA-PDMS) containing vinyl ester of versatic acid/vinyl acetate (Veova-10/VAc) was prepared by emulsion copolymerization of (DA-PDMS), Veova-10 (with VAc), and auxiliary agents at $85^{\circ}C$ in the presence of ammonium peroxodisulfate (APS) as an initiator. Sodium dodecyl sulfate (SDS) and nonylphenol ethylene oxide-40 units (NP-40) were used as anionic and nonionic emulsifiers, respectively. The resulting copolymers were characterized by using Fourier transform infrared spectroscopy (FT-IR). Thermal properties of the copolymers were studied by using thermogravimetric analysis(TGA) and differential scanning calorimetry (DSC). The morphology of copolymers was also investigated by scanning electron microscopy (SEM) and then the effects of variables such as temperature, agitation speed, surfactant kinds, molecular weights, initiator, and DA-PDMS concentrations on the properties of the silicone-containing Veova-10/VAc emulsions were examined. The calculation of monomer conversion versus time histories indicates that by increasing the DA-PDMS concentration the polymerization rate and the number of polymer particles decrease, respectively.

• Korean Journal of Microbiology
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• v.33 no.3
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• pp.181-186
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• 1997

Sugar ester compounds were synthesized in organic solvent using lipase. Anhydrous pyridinc was selected as ;I solvent because of reasonable solubility of sugar. The synthesis of sugar ester compound was catalyzed by Pseudomonas sp. lipase in the reaction system containing anhydrous pyridine as .i solvent and vinyl butylate as an acyl donor. The analysis of the reaction product by TLC and GC showed thilt monobutyryl and dibutyryl fructose esters were synthesized by transesterification reaction between fructose and vinyl butyrate. Optimal conditions for the transesterification reaction were as follows: the ratio of fructoselvinyl butylate, I : lO(M : M): reaction temperature, 40^{\circ}C.$, velocity of shaking, 150 rprn: concentration of enzyme, 10 mglml. The longer the reaction period, the higher the conversion rate, and the conversion rate reached up to 90% after about 10 days of reaction. Monobutyryl fructose was mainly synthesized in the early stage of reaction, but the amount of dibutyryl fructose increased gradually as the rcdction progressed. When a small amount of water was added to the reaction mixture (micro-water system), the reaction rate decreased, while that of rnonobutyr~l fructosc increased. Only monobutyryl fructose was obtained when 1% water was added to the reaction mixture.