콘크리트-폴리머 복합재료 개발(Ⅱ) : Physical Properties of Polymer(Resin) Concrete 폴리머(레진) 콘크리트의 물성

황의환,길덕수,황택성 공주대학교 자원재활용 신소재 연구센터 1999 1차년도 센터 성과집 Vol.1999 No.-

고기능성 건설재료로 활용하기 위하여 불포화폴리에스테르수지를 사용한 폴리머 콘크리트의 물성에 대하여 조사하였다. 탄산칼슘(충전제)의 첨가량(5~20 wt %)과 세골재의 첨가량(10~50 wt %)에 따라 다양한 공시체를 제작하여 압축 및 휨강도, 흡수시험, 내열수성시험, 내산성시험, 세공분포측정 및 SEM에 의한 미세조직 관찰등을 실시하였다. 그 결과 폴리머 콘크리트의 압축강도와 휨강도는 시멘트 콘크리트보다 4배 정도 향상되었고 흡수율은 1/100로 가소되었으며, 내산성시험에 의한 중량감소율은 1/27로 현저히 감소되었다. 내열수성시험후에 측정한 폴리머 콘크리트의 압축 및 휨강도는 모두 내열수성시험전에 측정한 강도에 비하여 67%, 47%로 각각 감소되었으며 폴리머결합체의 분해에 의하여 세공율은 크게 증가되었다. The phsical properties of polymer concrete were investigated for development of high performance construction materials. Various specimens of polymer concrete were prepared using unsaturated polyester resin as the ploymer binder with the various dosge of clcium carbonate as microfiller (5~20 wt %) and fine aggregate(10-50%). For the evaluation of the physical properties of polymer concretes, tests such as compressive strength, flexural stength, water absorption test, hot water immersion test, acid resistance test and pore size distribution analysis were conducted. As a result, it is concouded that compressive and flexural strengths of ployemr concretes increased up to 4times than those of conventional cement concrete. Whereas the compressive and flexural strengths of polymer concretes tested after hot water immersion, compared volume and porosity(%) of polymer concretes were remarkably increased due to decomposition of polymer binder. And also, it is showed that water absorption(%) and weight loss(%) of polymer concrete specimens by acid immersion, compared with those of ordinary portland cement cocrete decreased about 1/100, 1/27, respectively.

에틸렌 염회비닐 공중합체의 열분해 특성연구

황택성,서정목,맹기석,송해영 忠南大學校 産業技術硏究所 1987 산업기술연구논문집 Vol.2 No.2

PVC has been developed very rapidly as one of general useful resins, and many scientists have studied complimentary method for thermal stability to improve the disadventages of PVC. This study investigated to promote thermal stability by a VC-Ethylene copolymer synthesis of copolymer syntheses. The effect of the thermal stability was studies with different portion of Ethylene-VC copolymer. As the result, when ethylene copolymer was introduced, the thermal stability was promoted. So this report described the process and the result for such analysis.

PVC부분환원에 의한 Ethylene-Vinylchloride 공중합체의 합성과 열특성

황태성,맹기석,구철회 忠南大學校 産業技術硏究所 1994 산업기술연구논문집 Vol.9 No.1

ST-DVB 공중합체에 tinhydride를 고정한 환원제로 PVC를 부분환원하여 EV copolymer를 합성하였다. 환원제와 EV copolymer의 구조를 FT-IR 분광법으로 확인하였으며, EV copolymer의 조성변화, Tg, 분자량 및 열안정성 등을 조사하였다. EV copolymer의 수율은 32%∼57%이었고, 평균분자량은 3 mole% DVB를 함유한 polymeric hydride 환원제를 사용한 반응의 경우 1.41x10⁴∼1.65x10⁴이었고, 5mole% DVB polymeric hydride 환원제 반응의 경우에는 1.61x10⁴∼1.68x10⁴이었다. 환원제량의 증가에 따라 EV copolymer내의 ethylene unit의 mole%는 증가하였으며, 최대 23.74 mole%이었고 3 mole% DVB를 함유한 polymeric hydride 환원제가 환원력이 더 우수하였다. DSC 분석결과 EV 공중합체의 Tg는 ethylene unit의 조성에 따라 2∼3개로 나타났으며, 높은 쪽의 Tg는 PVC의 Tg와 비슷하게 나타나는 것으로 보아 공중합체 내에 상당 부분의 PVC가 존재하고, 구조가 불균일함을 알 수 있었다. 또한 공중합체내의 ethylene unit mole%가 19.8 mole% 이상에서는 3개의 Tg가 나타났으며 이런 결과로부터 공중합체는 block 형태임을 확인할 수 있었다. 초기 열분해 온도는 240∼248℃로 PVC보다 모두 높았고, ethylene unit의 조성이 증가할수록 증가하는 것으로 보아 새로운 polymeric hydride에 의해 합성한 EV copolymer의 열안정성은 PVC의 부분 환원제로 적합함을 알 수 있었다. The ethylene-vinylchoride copolymers(EV copolymer) were synthesized by partial reduction of PVC using the ST-DVB copolymer supported organotin hydride as a reduction agent. The basic structures of EV copolymer and reduction agents were studied by FT-IR spectroscopy, and the mole ratio, the glass transition temperature(Tg), the molecular weight, and the thermal stability of copolymer were investigated. The yield of EV copolymer reached about 32-57 percent. Weight average of molecular weight(Mw) of EV copolymer ranged from 1.41∼1.65x10⁴to 1.61∼1.68x10⁴, measured by gel permeation chromatography(GPC) when 3 mole% and 5 mole% of divinylbenzene(DVB) were involved in reduction agent. Ethylene unit of EV copolymer was increased with increasing in the amount of reduction agent used in the partial reduction of PVC, and their molar content reached a maximum of 23.74 mole% when 3 mole% DVB involved reduction agent was used. Differential scanning calorimetry(DSC) experiments were performed on a series of EV copolymer for the purpose of studying the dependence of their thermal transition temperature upon their values were lower than that of homo PVC. On the other hand, it was found that there were three Tg when the ethylene unit in EV copolymer is above 19.84 mole%. This may indicate that EV copolymer has a structure of block copolymer. Initial thermal degradation temperature of EV copolymer was higher than by thermal gravimetry(TGA). From this result, it was found that thermal stability of EV copolymer by partial reduction of PVC using 3 mole%, 5 mole% reduction agents were increased with increasing in the amount of ethylene unit content in the copolymer.

폐타이어칩 보강 복합재의 제조와 결합재가 복합재의 기계적 물성에 미치는 영향

황택성,박진원 공주대학교 자원재활용신소재지역협력센터 2000 2차년도 센터 사업 성과집 Vol.2000 No.1

For the superior properties of mechanical and thermal aging, this investigation was carried out to develop the recycled of waste tire using various binders (Olefin, SBR Rubber, Polyurethane) for the reuse of the waste tire. In the experimental results show that the mechanical and the thermal aging properties of the composites decreased steadily with increasing content of the waste rubber. We obtained the excellent mechanical and thermal properties when the SBR which is a rubber adhesive was used. Because that total pore area was largen, interfacial adhesive force was weaken. And as the binder was dispersed in waste rubber, the mechanical and thermal aging properties were superior. This result was observed the same phenomena with morphologically.

C.D와 Democracy

黃澤周 韓國社會事業大學 地域社會開發硏究所 1987 地域社會開發論叢 Vol.9 No.-

This study examines the development of democracy, based upon the community development and its relationships, and tries development with a search of essential autonomvic consciousness and essentiality of self-governing funds. Democracy, the effectual and fittest model that elevates better life, expects us to give up inveterate ritualism and unconditional authority, and develop a rational participatory democracy model. It's indispensible condition is that sovereignty rests with the people. Therefore, the premise and substance of democracy is autonomic consciousness and self-governing funds. And the community development should be based the residents' common interests and needs since it might bring them to participate in, as hosts, a rational and creative initiative when they do this, the development is closely connected with their interest so the idea of participation and funds raise it with the faith for consultation. And this is characterized by the small training camp of democracy as an integration of the community development depens upon their consistant effort, and it may be the effective way to pro-duce a democratic atmosphere with the autonomic conception. Therefore this study examines the autonomic consciouness and democratic funds. In order to develop democracy, the first thing we have to do is to increase and improve the political participation of the masses but generally most developing contries have pressure to democratic participation in the process of modernizaton. However the restraint on participation can't last forever, and dictatorship, which is a lack of public consultation, results in dissatisfaction among the people, eventual violence to promote social instability, and the ultimate distruction of the political system. We can emphasise the development of the community as a bisic organization of democratism. This will enable people to have a we-ness of belonging and unification within the small country, the basis and source of society. And democracy is closely related to self-governing funds. This has been developed in most rich countries that amass wealth and stability, but Korea, as a country without resources and with a high population density, has historically made progress only around Seoul and its neigh-boring districts, and this has drained funds from other areas of this country. Thus many localities in this countryside have financial problems. While some big cities such as Seoul, Pusan, Inchon, and Taegu make rapid progress, others don't. The rural community is especially at stake, as the government has granted privileges in the industrial fields only. At this time, the rural community is need of some sort of assistance or solution to its problems. And it is important that an agricultural reform to enlarge farm land and make the most use of it be instituted, as well as a subsidy policy to pay off the farmers' debts and raise their income. In fact agriculture has been at a disadvantage to other fields in regard to production, Process, transportation and prices. Especially, their possession to improve their economy social and political status. It is widely recognized that popular participation in public affairs at the local level may stimulate commitment and thus logalty to the government. And it also allows them to participate freely and encourages the initiative of the fundamental conditions for democracy. As the concluding remark, the basis of the people's autonomic consciousness and self-governing funds should be the essential factors in accomplishing the community development and democracy.

Atactic Polypropylene에 대한 염회비닐의 그라프트 중합

황택성,민병철,맹기석 忠南大學校 産業技術硏究所 1987 산업기술연구논문집 Vol.2 No.2

Atactic Polypropylene, a byproduct obtained in the manufacture of isotatic polypropylene, has been synthesed under various reaction conditions. In this study, suspension graft polymerizations of Vinylchloride onto Atatic polypropylene were carried out in aqueous with benzoyl peroxide as initiator. The effect on the grafting efficiency and reaction rate was observed by varing APP concentration Also, reactivity onto each hydrogen is the most good tertiary hydrogen among primary, secondary and tertiary. If the vinyl chloride concentration contains small in the polymerization, graftmer have carbonyl group, abnomal structure.

폐 FRP/석분슬러지 충전 복합재의 제조 및 기계적 물성에 관한 연구

황택성,박진원,이철호 공주대학교 자원재활용신소재지역협력센터 2000 2차년도 센터 사업 성과집 Vol.2000 No.1

SMC 욕조 생산 시 발생하는 폐 FRP와 석재 가공공정에서 발생되는 석분슬러지를 재활용하기 위하여 불포화에스테르 매트릭스 수지에 분말 충전하여 복합재를 제조하였다. 또한 충전제와 매트릭스 간의 계면결합력을 향상시키기 의해 석분을 실란 커플링제 γ-methacryloxypropyltrime-thoxysilane (γ-MPS)로 전처리하여 복합재를 제조하고 기계적 물성 및 계면현상을 관찰하였다. 복합재의 굴곡탄성율은 석분함량이 10 wt%, 실란커플링제의 농도가 3 wt%일 때 가장 우수하였으며 석분 충전량이 증가함에 따라 감소하는 경향을 보였다. 또한 복합재의 초기 열분해온도는 352∼359 ℃이었으며 이 온도에서 중량감소율은 약 3%로 충전제의 양에 관계없이 거의 일정한 경향을 보였다. γ-MPS 처리에 따른 복합재의 물성변화를 관찰한 결과 충전제와 매트릭스 수지간 계면결합력인 증진되어 물리·화학적으로 안정한 결합을 이루고 있고 pull out현상이 발생하지 않음을 확인할 수 있었다 In order to recyle the FRP waste from SMC bathtubs and rock-crush sludge obtained as a byproduct of stones, the composite consisting of the FRP and rock-crush sludge and the unsaturated polyester matrix resin were prepared. To enhance the interfacial bonding force between the reinforcements and the matrix resin, the rock-crush sludge was treated with silane coupling agent, γ-methacryloxypropyltrimethoxysilane (γ-MPS ) and their mechanical properties and interface phenomena were examined. The flexural moduius of the composite containing 10 wt% rock-crush powder treated with 3 wt% silane coupling agent showed the maximum value. And also the initial thermal degradation temperature of composites were in the range of 352∼359℃. From these results, we observed that the weight loss of composites was almost constant regardless of the concentration of silane coupling agent. It is confirmed that the interface of the composites containing filler treated with γ-MPS was improved in that were were no pull-out phenomena between the reinforcement and matrix resin.

폐 FRP/Urethane Foam 충진 혼성복합재의 제조 및 기계적 물성에 관한 연구

황택성,신경섭,박진원 공주대학교 자원재활용신소재지역협력센터 2000 2차년도 센터 사업 성과집 Vol.2000 No.1

욕조 생산시 발생하는 폐 FRP와 냉장고 등 가전품과 폐단열재로부터 발생하는 폐우레탄폼을 흡음 및 경량판재로 재활용하기 위하여 불포화 폴리에스테르 매트릭스 수지에 보강하여 복합재를 제조하였다. 또한 충진재의 함량의 변화가 복합재의 기계적 물성에 미치는 영향과 기지와 보강재간의 계면현상을 관찰하였다. 충진제의 함량이 70 wt%인 복합재의 인장강도는 82.34MPa로 가장 우수하였으며, 인장탄성율은 보강재의 함량이 증가함에 따라 감소하였다. 또한 굴곡강도와 굴곡탄성율은 폐FRP의 함량이 70wt% 충진된 복합재가 가장 우수하였으며, 그 값은 각각 72.5, 958.4MPa이었다. SEM 관찰 결과 70 wt% 충진된 충진제 매트릭스 수지의 계면에서 pull out 현상이 확인되지 않았으며 균열도 발생하지 않았고, 매트릭스 수지내에 충진된 폐 FRP/우레탄폼 충진제가 잘 분산되어 있음을 확인할 수 있었다. The waste FRP oocured in the fabrication of SMC (sheet molding campound) bathtubs and the waste polyurethane foam occured in electronic manufacture and waste insulator were applied as a soundproof and light weight pannel in the waste FRP unsaturated polyester matrix resin composites to recycle. The effect of filler contents of the mechanical properties and interfacial phenomena of the filler and matrix on the composites was evaluated. The tensile strength of composites reached its maximum value of 82.34 MPa when the filler content was 70 wt%, and the more content of reinforcement is increased, the more tensile modulus was decreased. The flexural strength and modulus of csomposites, reinforced 70 wt% with filler content, were dominant compared to the other samples to 72.5 Mpa, 958.4 MPa respectively. When composite of reinforced 70 wt% with filler content, it was confirmed that pull out phenomena and cracks did not occur in the interface of reinforcement and matrix resin through the SEM observation. Also, waste FRP and urethane foam were dispersed well into matrix resin as filler.

한국 재래 나물콩 품종 및 계통의 콩나물 특성

황영현,이정동,조호영,권택화,정연신 慶北大學校農業科學技術硏究所 2002 慶北大農學誌 Vol.20 No.-

우수한 특성을 가진 나물콩 품종 육성을 위하여 국내 재래 나물콩 계통의 콩나물 특성을 분석한 결과는 다음과 같다. 1. 공시된 301품종 및 계통의 콩나물 전체길이의 범위는 9.5∼23.0cm, 하배축 길이는 5.9∼15.1cm, 뿌리 길이는 3.2∼9.2cm로 다양한 변이를 보였고, 수율에서도 121∼695%로 다양하게 분포하고 있다. 2. 공시된 301품종 및 계통의 종피색에 따른 콩나물 수율은 혼색종피종에서 409%로 가장 높게 나타났고, 백립중에 따른 콩나물 수율은 소립종일수록 높은 경향이었으며, 잔뿌리수는 흑색종피종과 갈색 종피종에서 현저히 적었다. 3. 콩나물 길이와 전체길이에 대한 뿌리길이의 비율, 수율을 기준으로 한 공시품종 및 계통들의 분포에서 장려품종보다 우수한 특성을 가지는 다수의 재래계통이 분포하고 있었다. 4. 콩나물 하배축의 색도는 백색도(L값)에서 장려품종이 재래계통에 비해 백색에 더 가까웠고, 적색도(a값)와 황색도(c값)는 장려품종보다 재래계통에서 높은 경향이었다. To develop good soybean varieties for sprouts. 285 indigenous lines and 16 recommending varieties were evaluated by the sprout and agronomic characteristics. The range of whole length, hypocotyl length, root length, and yield rate of sprouts was 9.5~23.0cm, 5.9~15.1cm, 3.2~9.2cm, and 121~695%, respectively. Yield rate of sprouts was the highest, 409%, in the lines of mixed seed coat color. At the same time, it was reversely proportional to seed weight : the smaller the seed weight, the higher the yield rate as in all other reports. The number of roots was significantly fewer in the lines of the black and the green seed coat color than others. Based on whole length, rate of root length, and yield rate of sprouts, many indigenous lines were evaluated much better than recommending varieties. In the hypocotyl color of sprouts, the brightness was higher in improved variety than indigenous lines but vice versa in redness and yellowness in general.

Gas-Liquid Chromatography를 이용한 사과 및 배 중의 농약 다성분 잔류분석법

박주황,김택겸,오창환,김정한,이영득,김장억 한국환경농학회 2004 한국환경농학회지 Vol.23 No.3

사과 및 배 시료에서 농약 다성분의 gas chromatography를 이용한 잔류분석법 확립을 위하여 199가지의 농약를 선정 하여 retention time 및 검출기에 따라 ECD 5 그룹 및 NPD 5 그룹의 10개 그룹으로 분류하였다. 시료의 종류에 따른 분석조건을 확립하기 위한 회수율 시험은 농약들의 log P_(ow) 값과 화학적 분류에 따라 총 18개 (ECD 11개, NPD 7개)의 농약을 선정하였다. 예비실험 후 확립된 분석방법에 따라 10개 그룹의 혼합 표준용액으로 사과 및 배에 대한 회수율시험을 행하였다. 그 결과, 총 196가지의 농약의 70%에 해당하는 사과에서 136개, 배에서 133개의 농약들에서 회수율 70에서 120%의 양호한 결과를 나타내었다. 그러나 사과에서 43개, 배에서 45개의 농약들이 70% 미만의 회수율을 보였고, fenvalerate는 120% 이상의 회수율을 나타내었으며, 사과에서 17개 및 배에서 18개의 농약들은 검출이 되지 않았다. 그러나 확립된 분석법은 SOP에 의한 신속하고 수월한 수행으로 농산물 중의 잔류농약을 검출 및 모니터링하는 목적에 적합하다고 사료된다. A rapid analytical method was developed to determine multiple pesticide residues in apples and pears using gas-liquid chromatography (GLC). The samples were extracted with water-miscible solvents and purified by cleanup procedures serially comprising liquid-liquid partition and solid-phase extraction (SPE). Each analyte was separated and determined by a high-resolution GLC equipped with electron-capture detector (ECD) and nitrogen-phosphorous detector (NPD). A total of 196 pesticides, which were previously classified into 5 groups each for ECD and NPD based on their retention behaviors on the capillary column and responses to the detector, were subjected to the recovery experiment. In compliance with the analytical criteria, 70 to 120% of recovery and less than 20% relative standard deviation, the proposed method could be successfully applied to analyze 136 and 133 pesticide residues in apples and pears, respectively, which enabled not only rapid screening but quantitation of the residues. Even though less reliability was resulted from unacceptable recovery range, rest of pesticides including 43 and 45 analytes in apples and pears, could be also detected for their identity. The proposed method, failed to cover 17 and 18 pesticides for apples and pears, which mostly showed high polarity or heat-lability but, could be suitable for fast surveilance or monitoring of fruit harvests.