• Bulletin of the Korean Chemical Society
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• v.28 no.9
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• pp.1493-1498
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• 2007

In this work, alkyl methacrylate-based microgels were synthesized by an experimental design method, and their sebum absorption characteristics were investigated. The results of fractional factorial experimentation indicated that the cross-linking agent content, solvent content, and stirring speed were the main parameters in the synthesis of the microgels. The suitable synthesis conditions were determined by the response surface design method. Through a study of the monomer and solvent effects, it was confirmed that the microgel shows the highest sebum absorption ratio when t-butyl methacrylate is used as a monomer or when acetone is used as a solvent. The optimal microgel synthesis conditions for cosmetic application were determined, and the resulting microgel had a mean particle size of 4.7 μm and a sebum absorption ratio of 435%.

• Journal of Pharmaceutical Investigation
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• v.21 no.2
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• pp.111-116
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• 1991

Dextromethorphan HBr (DMP HBr) ion exchange albumin microcapsules were prepared by the interfacial polymerization method. The incorporation of drugs in empty albumin microcapsules was more increased in case of glutaraldehyde (GA) and formaldehyde (FA) than terephthaloyl chloride (TC) as a cross linking agent. The amount of DMP HBr incorporated into empty albumin micorcapsules was augemented with increasing DMP HBr concentration and the amount of empty microcapsules in the incorporation medium. Increasing the salt concentration in the release medium, the release rate and the DMP HBr amount released from microcapsules were increased. The release rates of DMP HBr from microcapsules retarded considerably compared with DMP HBr powder.

• Journal of the Korean Chemical Society
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• v.64 no.6
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• pp.354-359
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• 2020

This research was conducted to analyze the compatibility of used monomers and produce the high functional contact lens material containing silicone monomers. Silicone monomer (Sil-OH), Trimethylsilylmethacrylate (TSMA) were used as additives for the basic combination of Polyhedral Oligomeric Silsesquioxane (POSS), methyl methacrylate (MMA) and methyl acrylate (MA). And also, the materials were copolymerized with ethylene glycol dimethacrylate (EGDMA) as the cross-linking agent, AIBN (thermal polymerization initiator) as the initiator. It is judged that the fabricated lenses of all combinations are optically excellent and thus used monomers have good compatibility. Measurement of the optical and physical characteristics of the manufactured hydrophilic lens material were varied in each case. Especially TSMA with POSS increases the oxygen permeability and Sil-OH with POSS increases the wettability by the addition of Sil-OH. These materials were considered to have compatibility each other, so it can be used in functional contact lens material.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.48 no.1
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• pp.61-66
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• 2016

In order to improve the bonding efficiency of starch adhesives and water resistance of corrugated board, mixing ratio of additives dosage was changed and its effects were analyzed. When the additives dosage was increased, bonding strength, vertical compression strength, bursting strength and water resistance were increased, because of hydroxyl groups or acetyl groups in starch adhesives and cellulose fibers of corrugated board were cross-linked by additives. When 1.0% glyoxal dosage was added, flat crush strength and vertical compression strength were increased. With 1.5% glyoxal, bonding strength and bursting strength were increased. However, 2.0% glyoxal dosage was added, most of strength except bursting strength were decreased. Thus, when the appropriate amount of additives are added during corrugated board production process, increased bonding efficiency of starch adhesives and higher water resistance of corrugated board can be achieved.

• Membrane Journal
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• v.25 no.5
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• pp.391-397
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• 2015

The porous support polyvinylidene fluoride (PVDF) with a salting out based on the hollow fiber membrane polyethyleneimine (PEI) and polyvinylsulfonic acid (PVSA) by coating with by phase separated and pressurization (PSP) method to produce a multilayer membrane. The resulting membranes were characterized under the various conditions, such as the heat treatment temperature, coating concentration, feed concentration, cross-linking time and cross-link agent concentration in terms of flux and rejection rate for NaCl 100 ppm solution at 4 atm. The best results were PEI 20,000 ppm and PVSA 1,000 ppm, PEI 15% with a 2% malic acid aqueous solution coated by PSP method the hollow fiber membrane heat-treated for 1 minute showed flux 24.3 LMH, the rejection of 82.1%.

• Textile Coloration and Finishing
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• v.34 no.1
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• pp.1-9
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• 2022

The durable FR treatments such Pyrovatex and Proban have been used for cotton fibers, while the finishes involve toxic ammonia or formaldehyde release during finishing process or finished products. In this study, ecofriendly flame-retardant treatment of cotton fabrics was carried out using UV-curable formulations of Vinyl bisphosphonic acid (VBPA), Acrylaminide and Triacryloylhexahydro-1,3,5-triazine, as a monomer, a comonomer and a cross-linking agent respectively, which can introduce a cross-linked copolymer networks. With an optimal finish formulation, the flame retardancy of LOI 29.8 was maintained even after 10 laundering cycles. In TGA analysis, the DTGA peak decreased from 389℃ to 252℃ and the amount of char yield increased from 6.1% to 46.1% compared to the untreated cotton. In addition, MCC analysis showed that Peak HR and THR decreased by 59.4% and 69.2% respectively, compared to the untreated cotton. The pyrolysis and combustion behaviors of the FR-treated cotton implied a condensed-phase flame-retarding mechanism.

• Journal of Fashion Business
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• v.18 no.5
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• pp.159-170
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• 2014

Recent concerns about the PFOA(perfluorooctanoic acid), have been increasing, which is generally applied in the water-repellent finishing process of textile products. It has been proven through animal testing to be harmful to humans, as possible carcinogens and neuro-toxic material. Thus U. S. Environmental Agency has gone as far as requiring the material to be eliminated in its entirety by 2015. As a viable alternative to this water-repellent finishing agent, the development of C6 product is gaining its popularity. The effects of PFOA finishing on the silk fabrics were examined, and we reviewed parameters of the needed process for optimizing appearance and functionality of silk fabrics treated with eco-friendly water-repellent finishing agent. Cross-linking agent affected the most on black color of reactive ink, among the physical properties. The contact angle reading was the highest in $8g/{\ell}$ of concentration for all fabrics. All the fabric specimens, subjected to the DTP and water repellent finishing, exhibited higher stiffness, where rayon specimen showed the highest, compared to the untreated specimens. The results may provide basic information leading to the development of value-added silk fabrics with water-repellency without excessive deterioration of the delicate appearance and inherent soft touch.

• Polymer(Korea)
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• v.33 no.4
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• pp.319-325
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• 2009

The solution polymerization was conducted to synthesize pressure sensitive adhesive for polarizer film using acrylic monomers. 2-Ethylhexylacrylate, butylacrylate, acrylic acid were used as acrylic monomers. The ratio was 2-ethylliexylacrylate:butylacrylate:acrylic acid=25:50:3.6 by reflecting $-40^{\circ}C$ of glass transition temperature in the pressure sensitive adhesive. When 1 wt% of coupling agent was added to the polymerized pressure sensitive adhesive, the light transmissivity was significantly increased. This result is due to the enhancement of adhesive power against liquid crystal cell by Si-O bond of coupling agents. Cross-linking agent was added by 0.5, 1.0, and 1.5 wt% with respect to the synthesized polymer. Initial tackiness decreased, while cohesion increased with increasing crosslinking agent. In the analysis of contact angle, the increase of crosslinking agents yielded the enhancement of surface energy, resulting in the decrease of contact angle. From the measurement of heat resistance, the acrylic pressure sensitive adhesive showed excellent heat resistance regardless of change in temperature and contents in crosslinking agent. In the observation of a cutting plane, the increased crosslinking agent represented a smoother and cleaner section. Comprehensively, the optimum additive amount of crosslinking agent was determined to be 1.0 wt% to monomer.

• Membrane Journal
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• v.24 no.4
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• pp.311-316
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• 2014

The polyacrylonitrile (PAN) hollow fiber composite membranes were prepared and their pervaporation performance was tested to concentrate the acetic acid aqueous solution. The coating of the composite membranes were confirmed by SEM images and the coating thickness was averagely $3.85{\mu}m$. As the crosslinking agent and the crosslinking temperature increase, the permeability decreases while the separation factor increases. Typically, the permeability $250g/m^2{\cdot}hr$ and the separation factor 13 were obtained for glutaraldehyde 13 wt% as the crosslinking agent and crosslinking temperature $140^{\circ}C$. And for the use of another crosslinking agent, poly (acrylic acid) 9 wt% and crosslinking temperature $140^{\circ}C$, the permeability $330g/m^2{\cdot}hr$ and separation factor 9 were obtained.

• Journal of Hydrogen and New Energy
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• v.25 no.6
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• pp.561-569
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• 2014

Ceria ($CeO_2$) was used to increase the durability of the membrane in the polymer electrolyte membrane water electrolysis (PEMWE) circumstance. The sulfonated polyether ether ketone (SPEEK) as polymer matrix was prepared in the sulfonation reaction of polyether ether ketone (PEEK) to improve electrochemical characteristics. After sulfonation reaction, the organic-inorganic blended composite membranes were prepared by means of sol-gel casting method with loading the highly dispersed $CeO_2$ and Cs-substituted molybdophosphoric acid (Cs-MoPA) with cross-linking agent (tetrapropyl orthosilicate). Consequently, the composite membrane CL-SPEEK/Silane 4wt%/Cs-MoPA/Ceria(1%) showed the improved characteristics such as 82% of water content, 0.11136 S/cm of proton conductivity at $80^{\circ}C$, 55.50 MPa of tensile strength and 4.37% of breeding out of MoPA.