2차 아미노기를 갖는 실리카 나노입자와 (메타)아크릴레이트 단량체와의 마이클 부가반응에 대한 분광학적 분석

전하나(Ha Na Jeon),하기룡(Ki Ryong Ha) 한국고분자학회 2012 폴리머 Vol.36 No.5

본 연구에서는 실리카 나노입자를 bis[3-(trimethoxysilyl)propyl]amine(BTMA) 실란 커플링제로 표면 개질한 후, 실리카에 도입되는 2차 아미노기인 -NH기와 Michael 부가반응이 가능한 acrylate기를 가지는 trimethylolpropane ethoxylate triacrylate(TMPET)와 3-(acryloyloxy)-2-hydroxypropyl methacrylate(AHM)로 표면 처리를 하여 반응성(meth)acrylate기를 가지는 brush를 도입하는 연구를 수행하였다. 1분자에 Michael 부가반응성이 있는 acrylate기를 3개 갖는 TMPET와 1분자에 반응성이 있는 acrylate기와 반응성이 없는 methacrylate기를 각각 1개씩 갖는 AHM을 사용하여, 처리 몰(mol)수의 변화가 실리카 표면에 도입되는 (meth)acrylate기에 미치는 영향을 Fourier transform infrared spectroscopy(FTIR), elemental analysis(EA) 및 고체 상태 cross-polarization magic angle spinning(CP/MAS) nuclear magnetic resonance spectroscopy(NMR)법을 사용하여 분석하였다. BTMA로 개질된 실리카를 TMPET로 처리하면, 액체상태의 순수 TMPET와 순수 BTMA의 반응과는 달리 TMPET 1분자당 3개씩 결합있는 acrylate기 대부분이 BTMA의 -NH기와 Michael 부가반응이 일어나는 것을 확인하였다. 따라서 BTMA로 처리한 실리카에 Michael 부가반응으로 반응성 (meth)acrylate기를 도입하기 위하여서는 AHM과 같이 Michael 부가반응성이 있는 acrylate기와 Michael 부가반응성이 없는 methacrylate기를 각각 1개씩 가지는 AHM을 사용하는 것이 필요함을 확인하였다. In this study, we modified silica nanoparticles with bis[3-(trimethoxysilyl)propyl]amine (BTMA) silane coupling agent to introduce secondary amino groups on the silica surface. After modification of silica, we investigated effects of different types of (meth)acrylate group containing monomers on the Michael addition reaction to introduce reactive (meth)acrylate groups on the BTMA modified silica surface. We used two kinds of (meth)acrylate monomers, trimethylolpropane ethoxylate triacrylate (TMPET) which has three identical acrylate groups, and 3-(acryloyloxy)-2- hydroxypropyl methacrylate (AHM) which has one acrylate and one methacrylate group. We used fourier transform infrared spectroscopy (FTIR), elemental analysis (EA) and solid state cross-polarization magic angle spinning (CP/MAS) nuclear magnetic resonance spectroscopy (NMR) to understand reactions between NH groups on the silica surface with (meth)acrylate groups of TMPET and AHM monomers. We found almost complete Michael addition reaction between all three acrylate groups of TMPET with NH groups on the BTMA modified silica. But, for the AHM treatment of BTMA modified silica, we found Michael addition reaction occurred only between acrylate groups of AHM and NH groups of silica surface, not between methacrylate groups of AHM and NH groups of BTMA modified silica surface.

지역특성에 따른 자연재해 위험성에 관한 연구

Ha-Na Jeon(전하나) 한국환경정책학회 2010 한국환경정책학회 학술대회논문집 Vol.2010 No.11

실리카 나노입자 표면에 결합된 2차 아미노기와 Poly(ethylene glycol) Diacrylate의 마이클 부가반응에 대한 연구

하기룡(Ki Ryong Ha),전하나(Ha Na Jeon) 한국고분자학회 2012 폴리머 Vol.36 No.6

본 연구에서는 실리카 나노입자를 우수한 내가수분해성을 가지는 dipodal 형태의 bis[3-(trimethoxysilyl)propyl] amine(BTMA) 실란 커플링제로 표면 개질한 후, 실리카에 도입된 BTMA의 2차 아미노기인 N-H기와 마이클 부가 반응이 가능한 acrylate기를 1분자당 2개씩 가지는 poly(ethylene glycol)diacrylate(PEGDA)로 표면 처리하여 acrylate 기를 실리카 입자 표면에 도입하는 연구를 수행하였다. PEGDA의 몰수 및 3가지 서로 다른 분자량의 PEGDA (M.W. 258, 575, 700) 처리가 실리카 표면에 도입되는 acrylate기의 구조에 미치는 영향을 fourier transform infrared spectroscopy(FTIR), elemental analysis(EA, 원소분석) 및 고체 상태 13C cross-polarization magic angle spinning (CP/MAS) nuclear magnetic resonance spectroscopy(NMR)법을 사용하여 분석하였다. 액체상태의 순수 PEGDA와 순수 BTMA를 같은 몰 비로 반응시키면 PEGDA 1분자당 2개씩 존재하는 acrylate기 중 1개 acrylate기는 순수 BTMA의 N-H기와 1:1의 비율로 마이클 부가반응이 일어나 β-amino acid ester를 형성하고, 나머지 1개의 acrylate기 는 남아서 중합반응이 가능한 단량체 합성이 가능하다. 하지만, BTMA로 개질된 실리카 입자를 PEGDA와 반응시 키면, PEGDA 1분자당 2개씩 결합있는 acrylate기 대부분이 실리카 입자에 결합되어 있는 BTMA의 N-H기와 마이 클 부가반응으로 β-amino acid ester를 형성하여, acrylate기의 C=C기 대부분이 C-C로 변화함을 확인하였다. We used dipodal type bis[3-(trimethoxysilyl)propyl]amine (BTMA) silane coupling agent to modify silica nanoparticles to introduce secondary amino groups on the silica surface. These N-H groups were reacted with three different molecular weights (M.W. = 258, 575, and 700) of poly(ethylene glycol) diacrylates to introduce different attached layer thicknesses on the silica surface by Michael addition reaction. After Michael addition reaction, we used several analytical techniques such as fourier transform infrared spectroscopy (FTIR), elemental analysis (EA) and solid state 13C cross-polarization magic angle spinning (CP/MAS) nuclear magnetic resonance spectroscopy to characterize introduced structures. We found almost complete Michael addition reaction of both two acrylate groups of PDGDA with N-H groups of BTMA modified silica to form β-amino acid esters. Between equimolar ratio of pure BTMA and pure PEGDA reaction, only one acrylate group of two acrylate groups of PEGDA reacted with N-H groups of pure BTMA to form β-amino acid ester and the other remaining acrylate group can be used to form a polymer later.

서울시 온실가스 감축목표 성과관리 모니터링 방안 연구

김운수 ( Woon Soo Kim ),전하나 ( Ha Na Jeon ),정남숙 ( Nam Sook Jeong ) 서울시정개발연구원 2011 연구보고서 Vol.2011 No.28

Climate change is today recognized as one of the most serious challenges to the global and local community. The IPCC has concluded that most of the observed warming in global average surface temperature that has occurred since the mid-20th century is very likely a result of human activities. Our society has also experienced climate change; warmer winters, hotter summers and incidences of more extreme weather. Average temperature in Seoul has warmed at a rate of approximately 2.4°C from 1908 to 2007 that is almost triple the global rate in the past 100 years (1906-2005). Climate change is not only bringing subtropical diseases rarely found but also increasing flooding as rainfall become more intense during the summer in Seoul. Hotter temperatures will increase public health risks, particularly for vulnerable populations such as the elderly, and place further strains on our infrastructure. Seoul has already planned for a contribution to climate change and implemented action plans. The target of reducing Seoul`s GHG emissions by 25% of 1990 levels by 2020 and by 40% of 1990 levels by 2030, Seoul should know the strength and weakness in carrying out the plan by monitoring performance in order to successfully achieve greenhouse gas reduction goals. The aim of this study is to provide a monitoring framework for performance management meeting GHG emission reduction target and suggest policy-directions of improving an GHG target management in Seoul, The suggestions of this study are summarized as follows, 1. Seoul GHG Assessment Tool: This study suggests developing ``Seoul GHG Assessment Tool`` that all steps of reducing greenhouse gas are integrated into one system in Seoul:the steps include reporting GHG inventory, setting targets and action plans of GHG reduction, and evaluating performance of meeting the target. It is expected to enhance Seoul`s ability of managing performance, thus contribute much to meeting GHG reduction target in Seoul. 2. use of Seoul GHG Information Management System: In general, it needs to manage exceedingly mass data in order to devise strategy for reducing greenhouse gas and analysis the inventory. When it is extremely costly to produce a new system, it is able to use Seoul GHG Assessment Tool or GHG management systems established by government: NGMS (National Greenhousegas Management System) and GEIS (Greenhouse gas Emission Information System), etc. 3, establishment of monitoring system: The policy conditions and methodologies related to global warming have continuously modified, therefore we should enhance the flexibility for adapting the change in Seoul. For example, IPCC has modified and updated ``guidelines for national greenhouse gas inventories`` since the first report, so Seoul should also adapt its greenhouse gas inventory according to their revision. It is natural that the revisal has an effect on national and local target for climate change. 4, annual progress reporting of GHG reduction plans: New York and London have published the annual progress reports which show their achievement and performance of climate change plans. Those play an important role as informing the progress of plans to citizen and officer. It should be pointed out that local society take part in the action plans, thus Seoul have a duty to report the action plans and performance. 5, introduction of energy management system (ISO50001): According to the implementation of GHG and energy target management that divides the greenhouse gas target into public and private sectors in Korea, some experts predict to increase the works of management greenhouse gas reduction in local government. It is able to reduce the burden of the policy implementation as applying international standard of energy management system (ISO50001). The system stresses the involvement of executive leadership, saying that top management must establish, implement and maintain an energy policy. They must identify the scope of the system, communicate its importance, ensure that appropriate targets and performance indicators are established and ensure that results are measured.

인천 도서지역의 해양환경자원과 관리실태분석

변병설 ( Byung Seol Byun ),전하나 ( Ha Na Jeon ) 한국경제지리학회 2008 한국경제지리학회지 Vol.11 No.4

Bis[3-(trimethoxysilyl)propyl]amine 커플링제로 개질된 실리카 나노입자의 실란화도 정량 분석

김정혜(Jung Hye Kim),하기룡(Ki Ryong Ha),전하나(Ha Na Jeon) 한국고분자학회 2012 폴리머 Vol.36 No.3

본 연구에서는 실리카 나노입자의 표면을 실란 커플링제인 bis[3-(trimethoxysilyl)propyl]amine(BTMA)을 사 용하여 개질하였다. BTMA의 가수분해 시간, 농도 및 개질 시간의 변화가 실리카 표면 개질 반응에 미치는 영향을 Fourier transform infrared spectroscopy(FTIR), elemental analysis(EA) 및 고체 상태 cross-polarization magic angle spinning(CP/MAS) nuclear magnetic resonance spectroscopy(NMR)법을 사용하여 분석을 수행하였다. 연구 결과 BTMA의 가수분해 시간, 농도 및 표면 개질 시간이 증가할수록 3737 cm-1에 나타나는 실리카의 고립 실란올 (isolated silanol) 피크의 세기는 점점 약해지고, 도입되는 BTMA의 -CH2 기에 의한 신축(stretching) 및 굽힘 (bending) 진동 피크는 점점 강하게 나타났다. EA 분석을 통한 N 및 C의 함량에서도 같은 경향을 나타내었다. BTMA를 사용한 실리카 입자의 처리 조건 중, BTMA의 농도 변화는 실리카 입자 표면과 반응하는 BTMA의 양에 큰 영향을 미치지만, BTMA의 가수분해 시간 및 표면 개질 반응 시간의 영향은 크지 않은 것으로 나타났다. In this study, we treated silica nanoparticles with bis[3-(trimethoxysilyl)propyl]amine (BTMA) silane coupling agent to modify their surfaces. We investigated the effects of BTMA hydrolysis time, BTMA concentration and BTMA treatment time on the degree of silanization reaction of silica nanoparticles. We used Fourier transform infrared spectroscopy (FTIR), elemental analysis (EA) and solid state cross-polarization magic angle spinning (CP/MAS) nuclear magnetic resonance spectroscopy (NMR) to obtain quantitative data. We found the decrease of isolated Si-OH peak intensity at 3747 cm-1 and the increase of -CH2 stretching and bending peaks with increasing hydrolysis time, concentration and treatment time of BTMA. EA analysis results also supported this trend. We found a strong effect of BTMA concentration on the degree of silanization of the silica particles, but weak effects of the hydrolysis time and the treatment time.

서울시 대기환경 개선목표 달성을 위한 오염물질 저감대책 수립연구

김운수 ( Woon Soo Kim ),최유진 ( Yu Jin Choi ),김정아 ( Jeong Ah Kim ),전하나 ( Ha Na Jeon ) 서울시정개발연구원 2011 연구보고서 Vol.2011 No.44

고속가공시 다중센서를 이용한 가공상태 감시 기술

김전하(Jeon Ha Kim),강명창(Myeong-Chang Kang),김정석(Jeong-Suk Kim),나승표(Seung-Pyo Na),김기태(Gi-Tae Kim) 한국생산제조학회 2000 한국공작기계학회 추계학술대회논문집 Vol.2000 No.10

고속가공시 다중센서를 이용한 가공상태 감시 기술

김전하,강명창,김정석,나승표,김기태 한국공작기계학회 2000 한국공작기계학회 추계학술대회논문집 Vol.2000 No.-

The high hardened materials that are remarkable in aspects of durability have been used for die and mold industry. As the high hardened materials are hard to machine, the high-speed machining is essential to manufacture these materials. Currently, in the general turning and milling, experiments to the tool wear monitoring have studied, but those have not applied in high-speed machining. In this study, the cutting mechanism was analysed by the cutting force according to cutting conditions, and the parameters to monitor the tool wear were selected from the tendency of the cutting force and acceleration according to cutting length in the high-speed machining of the high hardened materials(STD11).