• Elastomers and Composites
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• 제52권3호
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• pp.187-193
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• 2017

In this study, the effect of the cure, mechanical properties, and oil resistance of NBR (acrylonitrile-butadiene rubber)/peroxide compounds were investigated for various co-agents. NBR compounds were characterized using a swelling test, a rheometer (MDR), and a compression set test. Mechanical properties were tested with original compounds, heated in air and exposed to the ASTM No.1, IRM 903 oil. NBR compounds were prepared using peroxide as the crosslinking agent. Trimethylolpropane trimethacrylate (TMPTMA), triallyl isocyanurate (TAIC), and 1,2-polybutadiene (HVPBD) were used as co-agents. The NBR compounds containing TMPTMA and HVPBD lowered the scorch time, while the addition of TAIC did not significantly change the scorch time. NBR compounds containing TMPTMA increased the crosslinking density, while the addition of TAIC and HVPBD lowered the crosslinking density. Moreover, the addition of TMPTMA improved the oil resistance of the NBR compound.

• 센서학회지
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• 제17권2호
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• pp.143-146
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• 2008

Polymer-coated film SAW sensors have been fabricated and their sensing properties for toxic chemicals have been extensively investigated. Four types of the toxic chemical compounds of hydrogen cyanide(AC), carbonyl dichloride(CG), pinacolyl methylfluorophosphonate(GD), 2,2'-dichlorodiethylthio ether(HD) were used as target gases. SAW sensors using five different kinds of polymers were used to detect toxic chemicals and their gas sensing characteristics were investigated. The polymers used as the sensing materials were polyisobutylene(PIB), polyepichlorohydrin(PECH), polydimethylsiloxane(PDMS), polybutadiene(PBD) and polyisoprene(PIP). The recommendable mixing ratio of PIB, PECH, PDMS, PBD and PIP to solvents were 1:30, 1:40, 1:10, 1:30 and 1:30, respectively. The sensing characteristics of the SAW sensors were measured by using E-5061A network analyzer.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 추계학술대회 논문집 학회본부 C
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• pp.950-952
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• 1999

In this paper, we are studied a electrical properties study with P.D.GEORGE/STER LING Co. P.B 302-LV-2 POLYBUTADIENE RESIN which is used for VPI(Vacuum Pressure Impregnation)processing of field magnet and armature of traction motor in Korean national railroad at present was carried out its FT-IR (Fourier Transform Infra-Red) volume resistivity characteristics. The varnishes were experimented with the temperature range form $25[^{\circ}C]$ to $180[^{\circ}C]$ and applied voltage were supplied at 100, 250, 500, 1,000[V]. In this condition, the volume resistivity for specimens were measured. From the above study, the following data obtained for volume resistivity. It can be confirmed that velume resistivity with the increase of temperature is lower rapidly from room temperature to $130[^{\circ}C]$, and it is lower slowly at temperature higher than $130[^{\circ}C]$. Volume resistivity value is higher, according as the specimen is thick gradually. As the applied voltage is higher in the same temperature, volume resistivity value is lower.

• 분석과학
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• 제23권5호
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• pp.505-510
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• 2010

톨루엔에 녹인 폴리부타디엔을 탄소가루의 결합재로 사용하였을 때, 탄소반죽은 전극 제작 후 용매 증발에 의하여 기계적 물성을 보였으며, 이 성질은 탄소반죽전극 실용화의 선행조건을 충족시키는 것이었다. 부타디엔 고무를 결합재로 사용하여 새로운 효소전극을 제작하고, 그것이 정량적인 전기화학적 행동을 보이는지 확인하기 위하여 여러 가지 전기화학 속도론적 파라메터 즉 대칭인자, 교환전류밀도, 이중층의 축전용량, 시간상수, 최대전류, Michaelis 상수 등을 구하였다. 이 결과들은 부타디엔 고무가 탄소반죽전극 실용화에 추천할 만한 위한 결합재임을 보여 주는 것이었다.

• Elastomers and Composites
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• 제6권1호
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• pp.53-70
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• 1971

We have studied the blending effects of cis-1,4-polybutadiene (CBR) and styrene-tutadiene rubber at various blending ratios of 100 : 0, 70 30, 50 : 50, 30 : 70, 0 : 100, and of carbon black ISAF and HAP at various compounding ratios of 45 PHR, 55 PHR, 65 PHR, for tyre tread rubber. The results obtained are summerized as follows; 1. For tyre tread rubber, it was found to increased efficiency to use SBR polymer only than to use the blending ratio CB/SBR=30/70 below. But it was observed that the latter was adapted for the bus or truck tyre and the former for the passenger tyre. 2. Excellent efficiency was obtained in case of carbon black compounding ratio of 55%, and also the compounding of ISAF made better efficiency than that of HAF. 3. Carbon black was more efficient to SBR than to CB. 4. For the aging ratio, the compounding rubber of NR was the highest, and the ratio was decreased in order of the compounding rubber of oil-extended SBR or CB polymer only, the compounding rubber of non oil-extended SBR or CB polymer only, and the blending rubber.

• Elastomers and Composites
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• 제55권2호
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• pp.95-102
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• 2020

Currently, peroxide cure is a widely used cure system for rubber materials. To improve its effectivity, co-agents are used to enhance the peroxide efficiency and mechanical properties of rubber materials. Co-agents are multifunctional organic compounds that are highly reactive towards free radicals. These co-agents provide higher cross-link densities for a given peroxide concentration and improve the mechanical properties of peroxide-cured rubber composites. In this study, trimethylolpropane trimethacrylate (TMPTMA) and high vinyl 1,2-polybutadiene (HVPBD) were used as co-agents. In order to obtain a concentration that achieves a favorable balance between mechanical properties and co-agent concentration, this research investigated the effects of co-agent content on the curing characteristics, chemical structures, and mechanical properties of HNBR composites. Additionally, the heat aging properties and compression sets of HNBR composites were investigated. Based on the results, we found that the HNBR composites with TMPTMA co-agents exhibited higher Shore A hardness and 10% modulus and better heat aging resistance and compression set than that of the HVPBD co-agent. The heat aging resistance and compression set deteriorated with increasing HVPBD content.

• 한국추진공학회지
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• 제9권2호
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• pp.40-45
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• 2005

본 연구에서는 연소촉매인 Butacene과 $Cr_2O_3$를 함유하는 HTPB/AP 추진제 조성이 추진제의 friability에 미치는 영향을 조사하였다. Inston tensile tester와 strand burner를 이용하여 HTPB/AP 추진제의 기계적 특성과 연소속도를 측정하였다 추진제의 탄속에 따른 shot-gun과 closed bomb 시험 결과로부터 추진제의 friability를 계산하였다. 결론적으로, 추진제의 조성 중 Butacene의 함량이 많은 추진제 또는 AP $6{\mu}m$의 함량이 많은 추진제가 friability가 큼을 알 수 있었다.

• 한국추진공학회지
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• 제23권1호
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• pp.9-14
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• 2019

고체 추진기관의 HTPB 추진제는 저장소에서 저장소 환경에 따라 물리적, 화학적 노화가 진행된다. 추진기관 수명은 HTPB 추진제의 노화도에 의해 결정되며, 생산 초기에 점탄성 특성 및 노화 시험을 통해 예측된다. 본 논문에서는 생산 초기 물성 및 가속노화 시험을 통해 획득한 노화 물성과 장기 저장되어 자연 노화된 물성을 비교 분석하였다. 획득된 초기 및 노화물성 결과를 적용하여 중공형 그레인의 온도 하중에 의한 변형율을 분석하였다.

• Advances in materials Research
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• 제13권2호
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• pp.129-140
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• 2024

This study evaluates the ratio of Toluene di-isocyanate (TDI) functional group isocyanate (NCO) to the binder functional hydroxyl group (OH) in HTPB/AP/Al-based propellants on their mechanical properties, flow rate, and viscosity to determine the limitations of NCO/OH in the composition of solid propellants. The propellants consisted of hydroxyl-terminated polybutadiene (HTPB) polyurethane (PU), aluminum (Al) and tri-modal ammonium perchlorate (AP). The tri-modal AP consisted of 30% of coarse AP, 30% of medium AP, and 8% of fine AP. The ratio of NCO/OH varies from 0.73 to 0.85, with two binder percentages of 10.5% and 12%. An increase in NCO/OH ratio with 10.5% binder provided 20%, 95%, and 8 to 9% increments in UTS, modulus, and hardness, respectively. However, the propellant elongation, density, and flow rate decreased by 170%, 0.2%, and 11-12%, respectively. Viscosity increased 20% based on initial hour reading. The 12% binder provides 27%, 47%, and 5~6% an increment of UTS, modulus and hardness respectively. However, the propellant elongation, density, and flow rate decreased by 47%, 0.17% and 27%, respectively. The viscosity increased 30% based on initial hour reading. This study suggests the NCO/OH value of 0.77 and 10.5~11% binder content in propellant based on the mechanical properties, flow rate, and viscosity for better processing and pot life.

• 폴리머
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• 제34권2호
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• pp.159-165
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• 2010

리빙 음이온 중합에 의해 sec-BuLi으로 개시된 polystyryllithium (PSLi)과 polybutadienyllithium (PBDLi)의 연쇄 말단에 di(2-pyridyl)ketone(DPK)을 반응시켜 dipyridine이 말단 관능화된 폴리스티렌과 폴리부타디엔을 각각 합성하였다. 분자량이 1000~2000 g/mol인 PSLi과 PBDLi을 사용하여 TMEDA 존재하에서 말단 DPK-관능화 반응 후 GPC에 의한 분자량 특성분석과 $^1H$-NMR, $^{13}C$-NMR 분석에 의한 고분자 말단 구조 분석을 통하여 말단 관능화 수율과 함께 유기리튬의 피리딘 링 친핵성 부가 반응으로 인한 커플링 현상을 확인하였다. PBDLi에 DPK를 부가하는 일반적인 말단 관능화 방법에 비하여 역으로 부가하는 방법에서 최대 9% 정도의 커플링 정도와 86% 이상의 관능화 수율을 보였다. 이 반응에서 LiCl 첨가효과는 없었으며, 반응온도가 낮을수록 높은 관능화 수율을 나타내었다.