• Korean Chemical Engineering Research
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• 제56권3호
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• pp.303-308
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• 2018

본 연구에서는 리튬이차전지 음극활물질인 Silicon/Carbon (Si/C) 복합소재를 제조하여 바인더 및 첨가제가 전지성능에 미치는 영향을 조사하였다. Si/C 합성물은 마그네슘의 열 환원 반응을 통해 SBA-15 (Santa Barbara Amorphous material No. 15)를 제조한 후 페놀 수지의 탄화 과정을 통해 합성하였다. Si/C 음극소재는 충 방전, 순환전압전류, 임피던스 테스트를 통해 전기화학적 성능을 분석하였다. PAA 바인더를 이용한 Si/C 전지의 용량은 1,899 mAh/g으로 다른 바인더를 사용한 합성물보다 우수하였으며, 40 사이클 동안 92%에 달하는 높은 용량 보존율을 나타내었다. 또한, VC 첨가제를 사용한 전지의 경우 3,049 mAh/g의 높은 초기용량을 나타내며, 실리콘 표면에 보호막을 형성해 초기 비가역용량을 감소시켜줌을 알 수 있었다.

• 한국건축시공학회지
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• 제16권1호
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• pp.45-52
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• 2016

본 연구에서는 무시멘트 결합재(NCB)를 사용한 지반 그라우팅용 약액주입재의 B액 결합재의 종류, 결합재의 W/B 및 A액과 B액의 부피비에 따른 겔타임 및 호모겔강도의 변화 특성을 검토함으로써 무시멘트 결합재의 지반 그라우팅용 결합재로서의 적용 가능성을 검토하고자 하였다. 무시멘트 무기결합재는 당사에서 공동연구를 통해 개발된 시멘트를 대체할 수 있는 고로슬래그 기반의 친환경 무기결합재로서 화학조성비가 다른 NCB-1, 2, 3을 사용하여 실험을 진행하였다. 실험 및 현장 적용성 분석 결과, 겔타임 및 호모겔강도의 요구성능을 확보할 수 있는 결합재 종류별 W/B 및 A액과 B액의 부피비가 도출되었으며, W/B가 100~140%, A : B가 50 : 50~30 : 70인 조건에서 급결구간 및 중결구간의 경우 NCB가 OPC 대비 동일한 겔타임 수준에서 호모겔강도의 확보가 유리한 것으로 평가되어 NCB의 지반 그라우팅용 결합재로서의 적용이 가능할 것으로 판단된다.

• Composites Research
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• 제35권6호
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• pp.365-370
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• 2022

전기자동차 및 E-모빌리티 시장이 급속히 성장함에 따라 리튬이온전지는 현재 가장 주목받는 기술 중 하나로 여겨지고 있다. 따라서 높은 용량 및 출력, 급속 충전 성능을 가지는 고에너지밀도 전극 개발이 매우 중요한 상황이다. 고에너지밀도 전극 구현을 위해서 음극의 경우 실리콘, 주석 등 고용량 활물질 소재에 대한 연구가 진행되고 있는 상황이다. 하지만 이러한 고용량 활물질 소재는 전지의 충방전 과정 시 발생하는 부피팽창이 전지의 성능을 저하시키는 주된 원인이 된다고 알려져 있다. 따라서 활물질의 부피팽창을 완화할 수 있는 바인더 소재 개발이 매우 중요한 상황이며, 기존 PVDF, CMC/SBR계 바인더 뿐만 아니라 수용성 고분자(polyacrylic acid, polyvinyl alcohol, aliginate 등)를 이용한 바인더 소재 개발 연구가 많이 보고되고 있다. 이처럼 앞으로 리튬이온전지의 고성능화를 위해서 바인더는 매우 중요한 기술이 되었으며, 본 논문에서는 리튬이온전지용 음극 바인더 소재의 연구 동향을 살펴보고자 한다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2002년도 학술.기술논문발표회
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• pp.67-76
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• 2002

Self-leveling material(SLM) is one of the floor finishing materials which make flat surface like as water level by itself in a short time. So it is possible to increase construction speed and enhance economical efficiency. In this study, author intended to develop SLM for the industrial warehouse and factory loading heavy weight machinery and vehicles. The demanded properties for this type of SLM are above 20mm of flow value and above 300kgf/cm2 of 28-days compressive strength. To possess demended strength and fluidity, SLM have to be composed of many types of binders and chemical additives. So it is difficult to decide suitable mixing proportion of composition materials. In this study, author investigated the weight percentage effect of main composition materials for high-strength self-leveling material, by experimental design such as tables of orthogonal arrays and simplex design, and by statistical analysis such as analysis of variance and analysis of response surface. Variables of experiments were ordinary portland cement(OPC), alumina cement(AC), anhydrous gypsum(AG), lime stone(LS) and sand, and properties of tests were fluidity of fresh state and strength of hardened state. Results of this study are showed that suitable mix proportions of binders for the high strength self-leveling materials are two groups. One is 78~85.5% OPC, 7.5~9.5% AC, 9~12.5% AG and the other is 72.5~78% OPC, 9~12.5% AC, 13~l5% AG.

• 한국축산식품학회:학술대회논문집
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• 한국축산식품학회 2005년도 제36차 추계 학술발표대회
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• pp.131-135
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• 2005

In general, the application of HP contributes to improvement of functionalities of meat protein. In the current study, HP allowed the lower thermal processing of restructured meat product. Low thermal processing allowed fresh-like meat color which is one of problems in hot-set restructuring, while they showed slight discolorization induced by HP. In addition, HP processing combined with thermal processing could be achieved the palatable binding strength in restructured meat product. The addition of non-meat protein had an effect in binding strength. However, they showed no effect on water binding properties at 200 MPa, especially in milk proteins such as casein and whey protein. This is probably due to protein aggregation or to increase in surface hydrophobicity under HP. This result indicates that the application of HP on meat restructuring is more significant than the addition of binders. Therefore, the application of HP has apotential benefit in restructured meat product, and further investigations are needed.

• Computers and Concrete
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• 제19권2호
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• pp.133-142
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• 2017

Two-stage concrete (TSC), also known as pre-placed aggregate concrete, is characterized by its unique placement technique, whereby the coarse aggregate is first placed in the formwork, then injected with a special grout. Despite its superior sustainability and technical features, TSC has remained a basic concrete technology without much use of modern chemical admixtures, new binders, fiber reinforcement or other emerging additions. In the present study, an experimental database for TSC was built. Different types of cementitious binders (single, binary, and ternary) comprising ordinary portland cement, fly ash, silica fume, and metakaolin were used to produce the various TSC mixtures. Different dosages of steel fibres having different lengths were also incorporated to enhance the mechanical properties of TSC. The database thus created was used to develop fuzzy logic models as predictive tools for the grout flowability and mechanical properties of TSC mixtures. The performance of the developed models was evaluated using statistical parameters and error analyses. The results indicate that the fuzzy logic models thus developed can be powerful tools for predicting the TSC grout flowability and mechanical properties and a useful aid for the design of TSC mixtures.

• Geomechanics and Engineering
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• 제38권6호
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• pp.541-551
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• 2024

Bottom ash classifies as a hazardous industrial-waste material that adversely affects human health. This study proposes its mixing with controlled low strength materials (CLSM) as a probable recycling approach. To this end, experiments have been performed to investigate the applicability of bottom-ash-based CLSM that comprises eco-friendly soil binders, water, fly ash, and a combination of bottom ash and weathered granite soil. The physical and chemical properties of the weathered granite soil, bottom ash, fly ash, and soil binders are analyzed via laboratory tests, including X-ray diffraction and scanning electron microscopy. To determine an appropriate CLSM mixing proportion, the flowability test is first performed on three mixture types having three replacement ratios of fly ash each. Subsequently, compressive-strength tests are performed. Based on the results of these tests, four mixtures are selected for the freeze-and-thaw test to determine the appropriate mixing proportion. Finally, the ground model and soil-contamination tests are performed to examine the field applicability of the mixture. This study confirms that bottom-ash-based CLSM causes negligible soil contamination, and it satisfies the prescribed performance requirements and contamination standards in Korea.

• Korean Chemical Engineering Research
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• 제49권3호
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• pp.381-386
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• 2011

염료감응형 태양전지의 광전극용 바인더로 화학적으로 기능기 작용을 가진 식물성 오일인 maleinized acrylated epoxidized soybean oil(MAESO)를 이용하였다. 제조된 광촉매의 특성을 고찰하기 위해 FE-SEM, EDS, XRD, XPS, 그리고 질소 흡착법(BET) 분석을 수행하였다. 식물성 오일 바인더를 이용하여 제조된 $TiO_{2}$ 입자는 P-25 광촉매와 비교하여 볼 때 비표면적과 특정한 크기를 갖는 세공의 수가 증가하였는데 이는 광촉매에 기능기가 증가하였기 때문이다. 기능기가 첨가된 $TiO_{2}$ 입자 표면에서 OH 관능기는 9.9에서 16.62%로 증가하였다.

• 한국건축시공학회지
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• 제15권1호
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• pp.1-7
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• 2015

본 연구의 목적은 ALC 블록대체를 위한 고성능 기포콘크리트 배합설계를 개발하는 것이다. 대기양생 하에서 기포콘크리트의 고강도 발현(특히 초기재령에서)을 위하여 결합재 및 혼화제를 사전연구에서 다음과 같이 설계하였다. 규산3칼슘이 60% 이상인 보통포틀랜드시멘트에 무수석고 3%를 첨가하였으며, 폴리카르본산계 감수제에서 폴리알킬에테르 성분을 28%로 조절하였다. 이들 재료를 사용하여 물-결합재비와 단위결합재양을 변수로 기포콘크리트 11배합을 실험하였다. 배합된 기포콘크리트의 품질 및 실용성은 KS 규격의 ALC 블록의 요구조건 및 기존의 일반 기포콘크리트와 비교하였다. 실험결과 본 연구의 고성능 기포콘크리트는 ALC 블록의 요구조건을 만족하면서 높은 실용가능성을 보였다.

• 한국도로학회논문집
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• 제16권5호
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• pp.9-18
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• 2014

PURPOSES : The objective of this study is to evaluate the applicability of the pitch, which is produced during SDA petroleum upgrading process, as a pavement paving material. In order for the purpose, the physical and chemical properties of the pitch are analyzed, and then the various plasticizers are applied in the pitch. METHODS : Two types of pitch are selected from oil refinery companies, which are owned the SDA petroleum upgrading process. Also, two types of asphalt binders, PG 64-22 and PG 58-22, are employed to compare with the pitch because these two types of asphalt binders are currently used as paving materials. For the chemical property of the pitch, the composition of SARA (Saturate, Aromatic, Resin, Asphaltene), the elementary composition, and the functional group are analyzed. For the physical property of the pitch, the basic material property tests, such as penetration test, softening point test, flash point test, ductility test, and rotational viscometer test, are performed. Also, the DSR (Dynamic Shear Rheometer) test and the BBR (Bending Beam Rheometer) test are conducted using asphalt binder specimens obtained by both short term aging (Rolling Thin Film Oven, RTFO) and long term aging (Pressure Aging Vessel, PAV) processes. The rheological property of each pitch type is evaluated as a function of temperatures and loading cycles. PG 64-22 asphalt binder is used as a control material. RESULTS AND CONCLUSIONS : The Pitch may not be suitable for the pavement paving material without modifications, but the pitch can be used as alternatives of modified addictive or asphalt. If low molecular component, such as saturate and aromatic components, are added in the pitch based on the development of various plasticizers, it has a strong possibility for the pitch to be used as a alternative. However, in order to verify the performance property of the pitch, further research is needed.