• Advances in concrete construction
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• 제10권2호
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• pp.127-140
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• 2020

This study explores the feasibility of granite waste aggregate (GWA) as a partial replacement of natural fine aggregate (NFA) in binary blend self-compacting concrete (SCC) prepared with fly ash. Total of nine SCC mixtures were prepared wherein one was Ordinary Portland cement (OPC) based control SCC mixture and remaining were fly ash based binary blend SCC mixtures which included the various percentages of GWA. Fresh properties tests such as slump flow, T₅₀₀, V-funnel, J-ring, L-box, U-box, segregation resistance, bleeding, fresh density, and loss of slump flow (with time) were conducted. Compressive strength and percentage of permeable voids were evaluated in the hardened state. All the SCC mixtures exhibited sufficient flowability, passing ability, and resistance to segregation. Besides, all the binary blend SCC mixtures exhibited lower fresh density and bleeding, and better residual slump (up to 50% of GWA) compared to the OPC based control SCC mixture. Binary blend SCC mixture incorporating up to 40% GWA provided higher compressive strength than binary blend control SCC mixture. The findings of this study encourage the utilization of GWA in the development of binary blend SCC mixtures with satisfactory workability characteristics as a replacement of NFA.

• International Journal of Concrete Structures and Materials
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• 제7권3호
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• pp.239-249
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• 2013

In the present scenario to fulfill the demands of sustainable construction, concrete made with multi-blended cement system of OPC and different mineral admixtures, is the judicious choice for the construction industry. Silica fume (SF) and fly ash (FA) are the most commonly used mineral admixtures in ternary blend cement systems. Synergy between the contributions of both on the mechanical properties of the concrete is an important factor. This study reports the effect of replacement of OPC by fly ash (20, 30, 40 and 50 % replacement of OPC) and/or silica fume (7 and 10 %) on the mechanical properties of concrete like compressive strength and split tensile strength, with three different w/b ratio of 0.3, 0.4 and 0.45. The results indicate that, as the total replacement level of OPC in concrete using ternary blend of OPC + FA + SF increases, the strength with respect to control mix increases up to certain replacement level and thereafter decreases. If the cement content of control mixes at each w/b ratio is kept constant, then as w/b ratio decreases, higher percentage of OPC can be replaced with FA + SF to get 28 days strength comparable to the control mix. A new method was proposed to find the efficiency factor of SF and FA individually in ternary blend cement system, based on principle of modified Bolomey's equation for predicting compressive strength of concrete using binary blend cement system. Efficiency factor for SF and FA were always higher in ternary blend cement system than their respective binary blend cement system. Split tensile strength of concrete using binary and ternary cement system were higher than OPC for a given compressive strength level.

• Elastomers and Composites
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• 제56권4호
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• pp.234-242
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• 2021

The demand for truck bus radial (TBR) tires with enhanced fuel efficiency and wear resistance have grown in recent years. In addition, as the issue of particulate matter and air pollution increases, efforts are being made to reduce the generation of particulate matter. In this study, the properties of epoxidized natural rubber (ENR) containing a silica-friendly functional group were evaluated by considering it as a base rubber and varying the silica ratio in this binary filler system. The results showed that the wear resistance of the NR/BR blend compound decreased as the silica ratio increased. In contrast, the ENR/BR blend compound exhibited an increase in wear resistance as the silica ratio was increased. In particular, the ENR-50/BR blend compound showed the best wear resistance due to the presence of several epoxide groups. Furthermore, we observed that for tan 𝛿 at 60℃, higher epoxide content resulted in the higher T_g of the rubber, indicating a higher tan 𝛿 at 60℃. On the other hand, it was confirmed that increasing the silica ratio decreased the value of tan 𝛿 at 60℃ in all compounds. In addition, we measured the amount of wear particulate matters generated from the compound wear. These measurements confirmed that in the binary filler system, regardless of the filler type, the quantity of the generated wear particulate matters as the filler-rubber interaction increased. In conclusion, the silica filled ENR/BR blend compound exhibited the lowest generation of wear particulate matters.

• Elastomers and Composites
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• 제34권1호
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• pp.20-30
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• 1999

본 연구는 용융법에 의한 폴리아미드 6,6(PA 6,6)과 에틸렌-프로필렌 고무(EPM) 및 무수 말레인산 그라프팅 EPM(EPM-g-MA)과 블랜딩시 탄성중합체 함유량 변화에 따른 이성분 PA 6,6/ EPM[EPM-g-MA] 블랜드물과 EPM:EPM-g-MA 조성비(wt%) 변화에 따른 삼성분 PA 6,6/ EPM/EPM-g-MA 블랜드물을 제조하여 블랜드물 내 탄성중합체의 평균 입자크기, 입자 형상 및 분포 등의 변화를 분석하고 이에 따른 블랜드물의 기계적, 열적 특성변화를 고찰하였다. 본 연구결과, 이성분 블랜드물 중 PA 6,6/EPM-g-MA 블랜드물은 PA 6,6/EPM 블랜드물에 비하여 EPM-g-MA의 평균 입자크기와 분포, 충격강도 및 상대결정화도 등이 향상되었고 PA 6,6/ EPM-g-MA 블랜드물 중 가장 큰 충격강도의 향상을 보인 PA 6,6/EPM-I-MA(70/30) 블랜드물은 폴리아미드 6,6의 충격강도에 비하여 약 25배 향상되었으며 상대결정화도는 약 7배 증가하였다. 그리고 삼성분 블랜드물 중 조성비가 70:15:15(PA 6,6 :EPM:EPM-g-MA)일 때 블랜드물 내탄성중합체 평균 입자크기는 $0.56{\mu}m$이면서 고른 입자분포를 얻을 수 있었을 뿐만 아니라 이러한 블랜드물의 충격강도는 제조된 모든 블랜드물의 충격강도에 비하여 가장 높았다.

• 공업화학
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• 제10권5호
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• pp.682-689
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• 1999

본 연구는 용융법에 의한 폴리아미드 6,6과 EPM 및 EPM-g-MA와 블렌딩시 탄성 중합체 함유량, 조성비(wt %), 혼합온도, 혼합속도 등의 변화에 따른 이성분 PA 6,6/EPM(or EPM-g-MA) 블렌드물과 삼성분 PA 6,6/EPM/EPM-g-MA 블렌드물을 제조하여 블렌드물 내 탄성 중합체 평균 입자 크기, 입자 형상 및 분포 등의 변화를 분석하고, 이에 따른 블렌드물의 기계적, 열적 특성에 미치는 영향을 고찰하였다. 본 연구결과, 혼합속도 250 rpm하에서 압출기 내 다섯 영역의 온도를 270, 265, 265, 255 및 $255^{\circ}C$로 변화시켜 탄성 중합체의 함유량 변화에 의하여 제조된 이성분 블렌드물중 높은 충격강도는 PA 6,6/EPM-g-MA(70/30) 블렌드물에서 확인되었으며 폴리아미드 6,6의 충격강도에 비하여 25배 증가하였다. 동일한 압출기 내 조건하에서 제조된 삼성분 블렌드물 중 PA 6,6/EPM/EPM-g-MA(70/15/15) 블렌드물 내 탄성 중합체 평균 입자크기는 $0.56{\mu}m$이면서 고른 입자분포를 나타내었으며 충격강도는 제조된 모든 블렌드물 중 가장 높았다. 이러한 블렌드물의 조성비하에서 혼합온도와 혼합속도 변화에 의하여 제조된 블렌드물의 기계적 특성과 블렌드물 내 탄성 중합체 분산정도는 감소하였다.

• Korea-Australia Rheology Journal
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• 제17권2호
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• pp.71-77
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• 2005

We investigated thermal, rheological, morphological and mechanical properties of a binary blend of poly(lactic acid) (PLA) and poly(butylene succinate adipate) (PBSA). The blends were extruded and their molded properties were examined. DSC thermograms of blends indicated that the thermal properties of PLA did not change noticeably with the amount of PBSA, but thermogravimetric analysis showed that thermal stability of the blends was lower than that of pure PLA and PBSA. Immiscibility was checked with thermal data. The rheological properties of the blends changed remarkably with composition. The tensile strength and modulus of blends decreased with PBSA content. Interestingly, however, the impact strength of PLA/PBSA (80/20) blend was seriously increased higher than the rule of mixture. Morphology of the blends showed a typical sea and island structure of immiscible blend. The effect of the blend composition on the biodegradation was also investigated. In the early stage of the degradation test, the highest rate was observed for the blend containing $80wt\%$ PBSA.

• Macromolecular Research
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• 제8권1호
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• pp.34-43
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• 2000

The melt rheology of four binary blends of ethylene 1-octene copolymers (EOCs) which consist of one component by Ziegler-Natta and another by metallocene catalysts, was studied to elucidate miscibility in the melt by using torsion rheometer at 200$\^{C}$ and different shear rates. The four blend systems, designated into the FA+FM, SF+FM, RF+EN, and RF+PL blend, are divided and interpreted based on the melt index (MI), the density and the comonomer contents. The melt viscosity such asη', η", and η$\^$*/ is weight average value if the comonomer contents are similar, otherwise they show different manner. The experimental resole are analyzed based on the Cole-Cole plot of logη' uersus log η", the logarithmic plots of the dynamic storage modulus (G') versus the dynamic loss modulus (G") for various blend compositions, and the melt viscosity of 11', n", and f" as a function of blend compositions. As a cerise-quence, the FA+FM blend is miscible, but the SF+FM, RF+EN, and RF+PL blends are not in the melt. Thus miscibility of the blends studied in this communication is suggested to strongly influence by the comonomer contents rather than the density or the MI.

• Fibers and Polymers
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• 제4권4호
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• pp.188-194
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• 2003

Phase behavior and spinodal phase separation kinetics in binary blends of a random copolymer of vinylidene fluoride and trifluoroethylene (75/25) [P(VDF/TrFE)] and poly(l,4-butylene adipate) (PBA) have been investigated by means of optical microscopic observation and time-resolved light scattering. The blends exhibited a typical lower critical solution temperature (LCST)∼${34}^{\circ}C$ above the melting temperature of the P(VDF/TrFE) crystals over the entire blend composition range. P(VDF/TrFE) and PBA were totally miscible in the temperature gap between the melting point of P(VDF/TrFE) and the LCST. Temperature jump experiments of the 3/7 P(VDF/TrFE)/PBA blend were carried out on a light-scattering apparatus from a single-phase melt state (${180}^{\circ}C$) to a two-phase region (205∼${215}^{\circ}C$). Since the late stage of spinodal decomposition (SD) is prevalent in the 3/7 blend, SD was analyzed using a power law scheme. Self-similarity was preserved well in the late stage of SD in the 3/7 blend.

• Structural Engineering and Mechanics
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• 제61권2호
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• pp.171-181
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• 2017

This paper summarizes the study on effect of ceramic waste powder as partial substitute to cement in binary blend and along with silica fume in ternary blend high strength concrete in normal and aggressive environments. Strength parameters such as compression & tension and durability indices such as corrosion measurement, deterioration, water absorption and porosity were studied. Ceramic waste powder was used in three different percentages namely 5, 10 and 15 with constant percentage of silica fume (1%) as substitutes to cement in ternary blend high strength concrete was investigated. After a detailed investigation, it was understood that concrete with 15% ceramic waste powder registered maximum performance. Increase of ceramic waste powder offered better resistance to deterioration of concrete.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2007년도 추계학술발표대회 및
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• pp.48.2-48.2
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• 2007