• 한국연초학회지
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• 제27권2호
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• pp.178-188
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• 2005

To use the filter materials for selective removal of carbonyl compounds in cigarette mainstream smoke, hydrazine such as 2,4-dinitrophenylhydrazine and dansylhydraznie impregnated adsorbents were prepared with perchloric acid or phosphoric acid as a accelerator in hydrazone formation reaction. The change of morphology of adsorbents in various of impregnator were investigated by SEM. Impregnation amount caused by reaction time, acid type and impregnation reagent, and the adsorption properties of carbonyl compounds in cigarette mainstream smoke were investigated. Amounts of impregnation was increased as increasing reaction time. The removal amount for vapor phase carbonyl compounds by 2,4-DNPH impregnated adsorbent was higher than that of dansylhydrazine impregnated adsorbent. The selectivity of 2,4-DNPH impregnated polyacrylic type adsorbent was superior to those of other adsorbents. This results indicated that the 2,4-DNPH impregnated polyacrylic adsorbent was applicable to cigarette filter material because of its fast reactivity and porosity.

• Journal of Electrochemical Science and Technology
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• 제10권2호
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• pp.131-138
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• 2019

To improve the performance of Si anodes in advanced Li-ion batteries, the design of the electrode plays a critical role, especially due to the large volumetric expansion in the Si anode during Li insertion. In our study, we used a simple fabrication method to prepare Si-based electrodes by grafting polyacrylic acid (PAA) to a carboxymethyl cellulose (CMC) binder (CMC-g-PAA). The procedure consists of first mixing nano-sized Si and the binders (CMC and PAA), and then coating the slurry on a Cu foil. The carbon network was formed via carbonization of the binders i.e., by a simple heat treatment of the electrode. The carbon network in the electrode is mechanically and electrically robust, which leads to higher electrical conductivity and better mechanical property. This explains its long cycle performance without the addition of a conducting agent (for example, carbon). Therefore, the partially carbonized CMC-g-PAA binder presented in this study represents a new feasible approach to produce Si anodes for use in advanced Li-ion batteries.

• 한국재료학회:학술대회논문집
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• 한국재료학회 1999년도 춘계학술발표강연 및 눈문개요집
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• pp.118-118
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• 1999

• 한국세라믹학회지
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• 제50권2호
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• pp.168-172
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• 2013

This work presents the effects of binders on the electrochemical performance of Si-C composites as the anode of lithium ion batteries. PAI (polyamide-imide) was used as an organic binder, and PAN (polyacrylonitrile), PAA (polyacrylic acid) and CMC + SBR (carboxymethyl cellulose + styrene-butadiene rubber) were used as aqueous binders. As a result, stabilization time for the cell with a Si-C composite anode synthesized using aqueous binders became shorter than an organic binder. Particularly in the case of the cell using PAA binder, better performance was observed in terms of adhesion strength, initial efficiency, the volume expansion ratio, Coulombic efficiency, and capacity retention.

• 공업화학
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• 제5권5호
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• pp.786-794
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• 1994

폴리머-시멘트 모르타르의 강도와 내구성에 대하여 검토하였다. 폴리머-혼화제로서 styrene-butadiene rubber(SBR) 라텍스, ethylene-vinyl acetate(EVA) 에멀젼 및 polyacrylic ester(PAE) 에멀젼을 사용하고, 폴린머-시멘트 비를 다양하게 변화시켜(5, 10, 15, 20 wt%) 공시체를 제작하였다. 내구성의 평가시험으로는 동결융해시험, 내산성시험 및 내열성 시험을 수행하였다. 폴리머-시멘트 모르타르의 내동해성은 폴리머-시멘트비가 증가될수록 현저히 향상되었으나 내산성과 내열성은 저하되었다. SBR 폴리머-시멘트 모르타르의 강도(압축 및 휨강도)는 폴리머-시멘트비가 증가될수록 향상되었으나 EVA 및 PAE 폴리머-시멘트 모르타르는 폴리머-시멘트비 10wt%에서 최대치를 나타내었다.

• 한국막학회:학술대회논문집
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• 한국막학회 1993년도 추계 총회 및 학술발표회
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• pp.58-58
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• 1993

Pervaporation has become important as a method to separate liquid mixtures, sepecially azeotropic and close boiling-point mixtures. Especially, water-alcohol separations have been carried out a lot because of the practical interests in the industries. However, outstanding membranes with high selectivity and high permeability have not been available in common use yet. In order to separate selectively out the water mixed with alcohols with an aim of the purification of the alcohols, a membrane has tO have excellent affinity to water. Among the hydrophilic polymers, polyacrylic acid and poly(vinyl alcohol) are used widely. In recent years, ionomers and polyion complexes, better hydrophitic materials, start to be used. The polyion complex membranes, consisting of polyacrylic acid (PAA) and polycation, showed excellent permeation rates and selectivities. It was known that among the polycations, ioneries, which have quaternary ammonium groups in the backbone chain, were more effective in giving membranes of higher permselectivities. On this base, syntheses and characterizations of the polycations, with different chemical structures from the published ones, for the polyion complex membrane formation were studied in this paper.

• 대한소아치과학회지
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• 제23권2호
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• pp.347-355
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• 1996

The purpose of this study was to compare the bond strengths of different kinds of glass ionomer cements (GIC), which is recently increasing the clinical application in the field of pediatric dentistry and measure the repaired bond strengths in order to examine the clinical applicabilty of partial repaired cases. By using one kind of the light cured type GIC and three kinds of the chemical cured type GIC, the bond strengths of the followings were compared : unrepaired group as control, repaired conditioning group, which was treated the repaired surface using 25% polyacrylic acid and repaired non-conditioning group without surface treatment. Three point bending test was performed under Universal Testing Machine in order to measure the compressive bond strengths. The results were as follows : 1. Light cured GIC had higher bond strength than chemical cured type GIC in both of repaired and unrepaired groups. 2. In repaired cases, all of the materials decreased the bond strength when compared to the control group. In the light cured type, the bond strength of repaired conditioning group decreased 31.6%, repaired non-conditioning group decreased 40.8%. In chemical cured types, the bond strength of repaired conditining group decreased 11.8%, repaired non-conditioning group decreased 20.9%. 3. All the materials, in the case of the chemical treatment on the repaired surface using 25% polyacrylic acid had higher bond strength than untreated but, lower than control group.

• 대한심미치과학회지
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• 제7권1호
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• pp.42-47
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• 1998

This study was performed to compare the bonding mechanism of glass ionomers. In this study, hybrid glass ionomers were used for restoration(Fuji II LC, GC, Japan) as the material of choice. Two different etching solutions were used in this study, 35% phosphoric acid and 10% polyacrylic acid. The effect of two different conditioners to dentin surface of a primary molar was studied and compared by using scanning electron microscope. Further, the interface of the dentin surface and the hybrid glass ionomers were examined.

• 대한치과교정학회지
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• 제27권2호
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• pp.327-334
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• 1997

광중합형 글래스 아이오노머 시멘트(Fuji Ortho $LS^{(R)}$)와 화학중합형 레진 시멘트(Mono $Lok2^{(R)}$)을 선택하여 사람의 소구치를 대상으로 법랑질을 퍼미스 및 10% 폴리아크릴산, 38%인산으로 표면처리한 후 금속 및 프라스틱 브라켓을 부착하고 섭씨 $37^{\circ}C$의 생리 식염수에 24시간, 48시간 경과 시키고 만능강도시험기를 이용하여 전단결합강도를 측정하고 비교함으로써 교정용 접착제로서 광중합형 글래스 아이오노머 시멘트가 임상적 적용 가능성이 있는지 여부를 규명하고자 시행하여 다음과 같은 결론을 얻었다. 1. 퍼미스로 법랑질을 표면처리한 광중합형 글래스 아이오노머 시멘트군의 전단결합강도는 화학중합형 레진군의 결합 강도보다 유의성 있게 낮았다(P<0.01). 2. 10% 폴리아크릴산으로 법랑질을 표면처리한 광중합형 글래스 아이오노머 시멘트군의 전단 결합강도는 화학중합형 레진군보다 유의성이 낮았다(PC0.01). 3. 10% 폴리아크릴산으로 법랑질을 표면처리한 광중합형 글래스 아이오노머 시멘트군의 전단결합강도는 피미스로 법랑질을 표면처리한 광중합형 글래스 아이오노머 시멘트군보다 약간 높았으나 통계적으로 유의성이 없었다(P<0.05). 4. 메탈과 플라스틱군의 법랑질 표면처리에 관계없이 통계적으로 유의성이 없었다(P<0.05). 이상의 결과를 종합해볼 때 비록 광중합형 글래스 아이오노머 시멘트가 화학중합형 레진 시멘트보다 결합강도는 낮지만 이의 임상적 적용은 가능할 것으로 사료된다.

• 폴리머
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• 제30권3호
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• pp.210-216
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• 2006

담배 주류연 중 카보닐 화합물의 선택적 감소를 위한 필터 물질을 제조하기 위하여 하이드라존 반응에 있어서 촉진제로 사용되는 과염소산과 인산을 2,4-dinitrophenylhydrazine (2,4-DNPH)와 dansylhydrazine (DAH)과 함께 각각의 흡착제에 첨착시켰다. 제조된 첨착 흡착제의 구조는 FTIR/ATR을 이용하여 확인하였으며 SEM을 이용하여 표면을 관찰하였다. 또한 첨착 시간과 촉진제 그리고 첨착 시약에 따른 첨착량과 담배 주류연 중 카보닐 화합물의 흡착특성을 조사하였다. 첨착량은 첨착 시간에 따라 증가되었으며 2.4-DNPH를 첨착한 흡착제의 경우 다른 흡착제에 비해 카보닐 화합물의 제거 효율이 우수하였다. 또한 폴리아크릴계 흡착제에 2,4-DNPH를 첨착시킬 경우 다른 기재의 흡착제에 비해 우수한 제거 효율을 나타내었는데 이러한 결과들로부터 궐련필터로의 적용 가능성을 확인할 수 있었다.