• 한국응용과학기술학회지
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• 제13권3호
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• pp.83-94
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• 1996

EMA-co-DAMA were synthesized from 2-diethylaminoethyl metacrylate and ethylhexyl metacrylate in acrylmonomer. To facilitate water emulsification, acrylic copolymer was cationized by acetic acid to produce acetated acrylic copolymer. The structures of the synthesized copolymer and acetated copolymers were confirmed by IR, NMR, and molecular weight was measure by GPC, and C.H.N elemental analysis. Acetated acrylic copolymers were perfectly emulsified in water and showed increased emulsion stability. Polymer dispersion for cement modifier[(PDCM-PED) water proof agent of cement for concrete in building construction] was prepared by blending of the guaternized acrylic copolymer syndisized above, sodium silicate, sodium gluconate and oleic acid emulsion. The result with prepared polymer dispersion of cement modifier was examined, and it was found that excellent waterprooffing effect ; Water permeability ratio is 0.50 under the water pressure of $100g/cm^2$ and 0.60 under $3kg/cm^2$, and water absorption ratio is $0.42{\sim}0.50$ and $1.0{\sim}1.02$ compressive strength ratio at mixed of water/PDCM-PED is 50 times.

• 공업화학
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• 제31권1호
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• pp.49-56
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• 2020

본 연구에서는 실란 커플링제 프로필트리메톡시실란(propyltrimethoxysilane, PTMS)을 사용하여 CaCO₃ 나노입자의 표면을 개질하였으며, 개질된 CaCO₃ 나노입자를 에멀젼 유화제 및 기포 안정화제로의 적용 가능성을 시험하고자 나노입자 표면의 소수성 변화가 기포와 에멀젼의 안정성에 미치는 영향에 관하여 살펴보았다. PTMS에 의한 CaCO₃ 나노입자의 표면 개질은 FT-IR, TGA, DSC 분석을 통하여 확인하였으며, XRD 및 XPS 분석을 통하여 나노입자 표면의 원소 분석을 실행하였다. 또한 부상 시험과 접촉각 측정을 통하여 PTMS 농도가 CaCO₃ 나노입자의 표면 개질에 미치는 영향에 관하여 살펴보았다.

• Macromolecular Research
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• 제15권6호
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• pp.498-505
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• 2007

This study demonstrated the in-situ functionalization with polymers of multi-walled carbon nanotubes (MWNTs) via emulsion polymerization. Polystyrene-functionalized MWNTs were prepared in an aqueous solution containing styrene monomer, non-ionic surfactant and a cationic coupling agent ([2-(methacryloyloxy)ethyl]trime-thylammonium chloride (MATMAC)). This process produced an interesting morphology in which the MWNTs, consisting of bead-string shapes or MWNTs embedded in the beads, when polymer beads were sufficiently large, produced nanohybrid material. This morphology was attributed to the interaction between the cationic coupling agent and the nanotube surface which induced polymerization within the hemimicellar or hemicylindrical structures of surfactant micelles on the surface of the nanotubes. In a solution containing MATMAC alone without surfactant, carbon nanotubes (CNTs) were not well-dispersed, and in a solution containing only surfactant without MATMAC, polymeric beads were synthesized in isolation from CNTs and continued to exist separately. The incorporation of MATMAC and surfactant together enabled large amounts of CNTs (> 0.05 wt%) to be well-dispersed in water and very effectively encapsulated by polymer chains. This method could be applied to other well-dispersed CNT solutions containing amphiphilic molecules, regardless of the type (i.e., anionic, cationic or nonionic). In this way, the solubility and dispersion of nanotubes could be increased in a solvent or polymer matrix. By enhancing the interfacial adhesion, this method might also contribute to the improved dispersion of nanotubes in a polymer matrix and thus the creation of superior polymer nanocomposites.

• 접착 및 계면
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• 제23권3호
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• pp.80-86
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• 2022

본 연구에서는 수계형 아크릴 점착제의 성능 및 점착 물성을 향상시키기 위해 분자량 조절제인 1-dodecanethiol(n-DM)의 함량이 다른 수계 아크릴 점착부여제를 합성하였으며 수계 아크릴 점착부여제의 투입량에 따른 물성 변화 확인을 위해 수분산성 아크릴 에멀젼에 수계 아크릴 점착부여제를 10/20/30 phr로 투입하여 물성을 측정하였다. 합성된 수계 아크릴 점착부여제의 분자량 및 유리전이온도(T_g)는 n-DM의 함량이 증가함에 따라 감소하는 경향을 나타내었다. 수분산성 아크릴 에멀젼에 수계 아크릴 점착부여제를 첨가하였을 때의 점착력 및 내열 유지력은 증가하였으며 수계 아크릴 점착부여제를 10 phr 또는 20 phr로 투입하였을 때에 가장 우수한 값을 나타내었다.

• Korean Chemical Engineering Research
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• 제52권6호
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• pp.789-795
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• 2014

초산은 묽은 산에 의해 처리되어 얻어진 헤미셀룰로오스 가수분해액 중 가장 양이 많을 뿐만 아니라 중대한 에탄올 발효 저해물질이다. 그 가수분해액으로부터 초산을 선택적으로 제거하는데 최적인 분리시스템을 찾기 위하여 모사 헤미셀룰로오스 가수분해액으로 자일로스, 초산과 황산의 혼합물이 선택되었다. 이러한 목적을 이루기 위해 에멀젼형 액막법이 모사 헤미셀룰로오스 가수분해액으로부터 초산을 제거하는데 적용되었다. W/O 에멀젼의 주요 구성 성분들, 즉 아민계 추출제 종류, 계면활성제 조성, 첨가제 종류와 회수제의 종류 및 농도가 모사 헤미셀룰로오스 가수분해액에 있는 초산, 자일로스와 황산의 추출에 미치는 영향이 조사되었다. 특별한 실험 조건에서, 초산의 추출율은 95% 이상이었고, 자일로스의 손실은 미미하였는데, 이것은 현 에멀젼형 액막법이 경제성이 높은 공정이 될 수 있다는 것을 의미한다.

• Journal of Pharmaceutical Investigation
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• 제28권2호
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• pp.87-92
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• 1998

Kojic acid (KA) is an antimelanogenic agent which has been widely used in cosmetics to whiten the skin color. However, it has the drawbacks of the skin irritancy and the instability against the pH, temperature, and light. In order to overcome these problems, various topical gels and multiple emulsion creams which can control the release of active ingredient, KA, were formulated employing cream bases of mineral oil with caprylic capric triglyceride and hydrophilic polymers such as chitosan, carbopol. and pluronics. Using Franz diffusion cells mounted with a synthetic cellulose membrane (MWCO 12,000), drug release characteristics of the formulations were evaluated by the HPLC assay of KA concentration in the receptor compartment of pH 7.4 phosphate buffered saline solution. Drug release from chitosan-based gels (ChitoGel) obeyed to the first order kinetics with a rapid release especially in the initial period. However, pluronic-based gels (PluGel) and carbopol-based gels (CarboGel) revealed controlled release of drug to some extent, followed by the square root-time kinetics. Moreover, the release of KA was further controlled with the W/O/W multiple emulsion creams (MultiCream), showing the apparent zero order release kinetics by virtue of dynamic ratecontrolling membrane of the oil layer. The flux $(J,\;{\mu}g/cm^2/hr)$ of ChitoGel. CarboGel. PluGel. and MultiCream in the initial period of 6hr were 73.30, 28.67. 24.04 and 7.72, respectively. On the other hand, the skin irritancy score of ChitoGel and MultiCream were observed as 2.5 and 2.3 respectively, in the rabbit skin irritation test. Although there were insignificant differences at p<0.05 between those formulations, it was possible to conclude that the W/O/W multiple emulsion creams containing KA might be a good candidate for an antimelanogenic drug delivery system due to the controlled release of acidic drug molecules.

• 한국축산식품학회지
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• 제43권3호
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• pp.502-511
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• 2023

The use of nitrite as a conventional curing agent is decreasing because of the negative consumer perception of synthetic compounds in foods. Therefore, this study was conducted to investigate the efficacy of dongchimi as an alternative to synthetic nitrite and its effect on the qualitative properties of emulsion-type sausages. Under all tested fermentation conditions, both nitrite and nitrate contents were the highest when dongchimi was fermented at 0℃ for 1 wk. The fermented dongchimi was powdered and added to the sausages. Emulsion-type sausages were prepared with 0.25% (treatment 1), 0.35% (treatment 2), 0.45% (treatment 3), or 0.55% (treatment 4) dongchimi powder, with 0.01% sodium nitrite-treated (control 1) and 0.40% celery powder-treated (control 2) sausages as controls. There were not different (p>0.05) in the pH, cooking yield, CIE L^*, and CIE a^* between the control 1 and treatments 2, 3, and 4. CIE b^* was significantly higher (p<0.05) in the control 2 and lower (p<0.05) in the control 1 than that in the other groups. Treatment 4 and control 1 had similar contents of residual nitrite, nitrosyl hemochrome, and total pigment. Additionally, treatment 4 exhibited a significantly better (p<0.05) curing efficiency than the control 1. However, naturally cured sausages showed higher (p<0.05) lipid oxidation than the control 1. This study suggests that the use of more than 0.35% dongchimi powder could replace sodium nitrite or celery powder as curing agents for emulsion-type sausages.

• 화약ㆍ발파
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• 제22권1호
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• pp.1-4
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• 2004

우리나라에서 전통적으로 사용해 왔던 제2세대의 젤라틴 다이너마이트 폭약은 경제구조와 안전의식 및 생활환경의 급변으로 제5세대의 에멀젼폭약으로 급변, 대체되고 있다. 이제 대량생산 및 발파기술의 도입으로 벌크에멀젼폭약의 상용화가 눈앞에 다가왔다. 그러나 에멀젼 폭약 제조기술의 중요한 요소인 계면활성제에 대한 연구발표가 부족하고 특히 그라스마이크로볼륨(GMB)의 사용기술은 전무한 실정이다. 실험실연구를 통하여 에멀젼 폭약 제조시 최적의 계면활성제를 알고 그의 효율적 사용법(최적반응온도 변화도)과 GMB의 혼합적정온도와 시점을 연구하여 제조공정에서의 경제성과 안전성을 향상시켰다.

• Food Science and Biotechnology
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• 제18권4호
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• pp.900-903
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• 2009

An oat gum was extracted from whole seeds of a drought harvested oat (Avena sativa). Oat gum presented a ${\beta}-glucan$ content of 65%(w/w) and an intrinsic viscosity of 141 mL/g. Gelling capability of oat gum at different concentrations was investigated. Gel hardness increased from 0.08 to 0.25 N as the oat gum concentration changed from 5 to 10%(w/v). Whippability, foam stability, emulsion stability, and reduced viscosity of oat gum at different pH were also investigated. Oat gum whippability was maximum at pH 7 (146%), while the higher foam and emulsion stability values were found at pH 9 (88 and 96%, respectively). The gum reduced viscosity increased from 715 to 958 mL/g as the pH changed from 7 to 9. Oat gum shows great potential as a gel forming, thickening, and stabilizing agent.

• 한국응용과학기술학회지
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• 제21권3호
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• pp.191-196
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• 2004

An emulsion of octadecamidoethylaminoethyl dodecate (which provides softness) and an emulsion silicone oil KF-96 (which provides lubricity) were separately synthesized. Then PP finishing softeners (SSA-7) was prepared by blending of the synthesized emulsions with beef tallow hardened oil (a softness improving agent). PP finishing treatment was carried out with the prepared SSA-7 and PP finishing resin by a one bath method, and several physical properties were tested. As a result, crease recovery, tear strength, softness, lubricity, and bending resistance were all good, indicating that the prepared SSA-7 is a good PP finishing softener.