• Transactions of the Korean Society of Automotive Engineers
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• v.22 no.4
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• pp.1-9
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• 2014

The vast stores of biomass available in the worldwide have the potential to displace significant amounts of petroleum fuels. Fast pyrolysis of biomass is one of several paths by which we can convert biomass to higher value products. The wood pyrolysis oil (WPO) has been regarded as an alternative fuel for petroleum fuels to be used in diesel engine. However, the use of WPO in a diesel engine requires modifications due to low energy density, high water contents, high acidity, high viscosity, and low cetane number of the WPO. One possible method by which the shortcomings may be circumvented is to co-fire WPO with other petroleum fuels. WPO has poor miscibility with light petroleum fuel oils; the most suitable candidates fuels for direct fuel mixing are methanol or ethanol. Early mixing with methanol or ethanol has the added benefit of significantly improving the storage and handling properties of the WPO. For separate injection co-firing, a WPO-ethanol blended fuel can be fired through diesel pilot injection in a dual-injection dieel engine. In this study, the performance and emission characteristics of a dual-injection diesel engine fuelled with diesel (pilot injection) and WPO-ethanol blend (main injection) were experimentally investigated. Results showed that although stable engine operation was possible with separate injection co-firing, the fuel conversion efficiency was slightly decreased due to high water contents of WPO compare to diesel combustion.

• Applied Chemistry for Engineering
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• v.4 no.2
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• pp.349-357
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• 1993

Polyarylate(PAR)-nylon 6 block copolymers of various block lengths were prepared by the anionic polymerization of ${\varepsilon}$-caprolactam using the polymeric activator from hydroxy-difuncrtional PAR and toluene diisocyanate. Phase separated morphology of PAR-nylon 6 block copolymer was suggerted from the thermal properties measured by differential scanning calorometry(d.s.c.). Partial miscbility between PAR block and nylon 6 block of the block copolymers was more evident at shorter length of constituent blocks. In binary blends of PAR-nylon 6 block copolymer with PAR or nylon 6 homopolymer, molecular-level mixing of homopolymers with corresponding blocks of block copolymer was supposed from the thermal properties measured by d.s.c..

• International Journal of Highway Engineering
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• v.10 no.3
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• pp.239-246
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• 2008

In this study, the influence of reaction temperatures, mixing time and flexible modifier for crumb rubber modified asphalt(CRMA) as processing conditions were investigated. The temperature susceptibility and adhesion properties of neat and modified asphalts at low temperature measured using the penetration and tensile adhesion test. It was found that processing temperatures and flexible modifier were important factors for tensile adhesion strength and toughness energy at low temperature. The CRMA in the higher processing temperature and flexible modifier exhibited improved tensile adhesion properties which indicated the flexible structure of neat and modified asphalt binder. In general, the improvements of the physical properties in the CRMAs were due to the improvements of miscibility between CR and asphalt binder. It was found that the adhesion properties of the flexible agent modified CRMA were higher than CRMA were related to the flexible agent tend to penetrate into CR particles and asphalt binder.

• KSBB Journal
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• v.20 no.3
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• pp.183-191
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• 2005

Ionic liquids, composed of organic cations and either organic or inorganic anions remain liquid over a wide range of temperature. ionic liquids are a new group of solvents or extractants of great interest as a potential 'green solvent'. Ionic liquids are gaining wide recognition as novel solvents in many research fields, such as chemistry, chemical engineering, electrochemitry, etc. However, not much researches have been done related to biotechnology using ionic liquids, while a lot of researches have been performed in chemistry. The merits of ionic liquids in bioseparation technology are originated from some unique properties of ionic liquids, such as negligible vapor pressure, good thermal stability, controllable viscosity and miscibility with water and organic solvents. An appropriate selection of ionic liquid for bioprocesses requires basic knowledge on physicochemical properties of ionic liquids. This review gives a brief overview on the application of ionic liquids in biotechnology, including bioconversion and bioseparation.

• Polymer(Korea)
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• v.26 no.1
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• pp.71-79
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• 2002

RPP(maleic-anhydride grafted PP)and OPS(oxazoline grafted PS) do not react to each other, and thus show immiscibility. In this study, Nylons was added to RPP/OPS blend systems, as a reactive compatibilizer for enhancing the miscibility of the blends. When Nylon6 was added to the blends of RPP and OPS, RPP/Nylon6/OPS was produced. The effects of the molar ratio of Nylon6 on the RPP-Nylon6-OPS reaction were studied. Torque test and FT-IR analysis have been carried out to investigate the reaction of RPP/Nylon6/OPS system. The reaction torgue ratio and reaction efficiency show the maximum values at 1 : 0.66 : 1 and 1 : 1 : 1 (in moles) for RPP/Nylon6/OPS. In the RPP/Nylon6/OPS blends, their mechanical properties were changed with the molar ratio of Nylon6 and showed the highest value at molar ratio of 1.5. Physical properties and compatibility of RPP/Nylon6/OPS were compared with those of PP/Nylon6/OPS. Consequently, RPP/Nylon6/OPS plays a proper role as a reactive compatibilizer to the PP/PS blend system.

• Polymer(Korea)
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• v.36 no.5
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• pp.617-621
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• 2012

PHEAs [${\alpha}$,${\beta}$-poly(2-hydroxyethyl-DL-aspartamides)], a class of poly(amino acid), have been widely studied as biodegradable and biocompatible polymers for potential biomedical and pharmaceutical applications. In this study, we investigated a homogeneous blend of PHEA with poly(N-vinyl pyrrolidone) (PNVP) and its semi-IPN (semi-interpenetrating polymer network) gels. Blend films were prepared by a solution casting method. The resulting blends were totally transparent over the whole composition ranges and the single $T_g$, changing monotonously with composition, was observed by DSC to confirm the miscibility between these two polymers. FTIR was used to discuss the possible hydrogen-bonding interaction between polymers. In addition, semi-IPN type gels were prepared by chemical crosslinking of PHEA/PNVP blend solution using hexamethylene diisocyanate (HMDI) as a crosslinking reagent. The prepared gel was characterized by their swelling property and morphology.

• Journal of Adhesion and Interface
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• v.2 no.1
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• pp.18-22
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• 2001

Surface morphology of [poly(vinylidene fluoride)/poly(methyl methacrylate)] (PVDF/PMMA) was investigated on the basis of atomic force microscopy and differential scanning calorimeter measurements. The surface of (PMMA/PVDF) and (H14-PMMA/PVDF) blend films was fully composed with PVDF crystals. Although the difference of surface free energy between PMMA and PVDF is increased with increasing carboxyl group content in PMMA, however, in the case of (H24-PMMA/PVDF) blend film surface, the existence of aggregated H-PMMA was observed. It was found that the degree of surface enrichment of the blend is more affected by the magnitude of intermolecular interaction than the surface free energy difference, Besides, the introduction of carboxyl group for miscible (PVDF/PMMA) blend decreased the miscibility in the blend.

• Macromolecular Research
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• v.15 no.2
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• pp.95-99
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• 2007

The most recent developments in two areas: (a) synthesis of inorganic particles with control over size and shape by polymer additives, and (b) synthesis of inorganic-polymer hybrid materials by bulk polymerization of blends of monomers with nanosized crystals are reviewed. The precipitations of inorganics, such as zinc oxide or calcium carbonate, in presence and under the control of bishydrophilic block or comb copolymers, are relevant to the field of Biomineralization. The application of surface modified latex particles, used as controlling agents, and the formation of hybrid crystals in which the latex is embedded in otherwise perfect crystals, are discussed. The formation of nano sized spheres of amorphous calcium carbonate, stabilized by surfactant-like polymers, is also discussed. Another method for the preparation of nanosized inorganic functional particles is the controlled pyrolysis of metal salt complexes of poly(acrylic acid), as demonstrated by the syntheses of lithium cobalt oxide and zinc/magnesium oxide. Bulk polymerization of methyl methacrylate blends, with for example, nanosized zinc oxide, revealed that the mechanisms of tree radical polymerization respond to the presence of these particles. The termination by radical-radical interaction and the gel effect are suppressed in favor of degenerative transfer, resulting in a polymer with enhanced thermal stability. The optical properties of the resulting polymer-particle blends are addressed based on the basic discussion of the miscibility of polymers and nanosized particles.

• Polymer(Korea)
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• v.33 no.3
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• pp.248-253
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• 2009

Blend films based on the poly($\varepsilon$-caprolactone) (PCL) and amphiphilic biodegradable polymer, poly(ethylene glycol) grafted poly($\varepsilon$-caprolactone) (PCL-g- PEG), were prepared with different blend ratios in order to develop new biomedical material. PCL was the main component in the blend. The miscibility and characteristics of the blends were investigated. The crystallization temperature of the blend shifted to high temperatures with an increase of the graft copolymer contents when the homopolymer PCL was the main component of the blend. The PEG side chain in the blend affected the crystallization rate of the PCL crystals in the blend and alternating extinction bands were observed by optical microscopy. The protein adhesion behavior of the film was influenced by the water uptake of the film.

• Elastomers and Composites
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• v.36 no.3
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• pp.169-176
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• 2001

Ethyl-branched polyethylene[PE(2)] containing 2mole% ethyl branch and three ethylene-propylene rubbers(EPR's) haying the same ethylene(E)-propylene(P) molar ratio(E/P=50/50) with different stereoregularity, that is, random EPR(r-EPR), alternating-EPR(alt-FPR) and isotactic-alternating-EPR(iso-alt-EPR) were mixed for the investigation of their properties depending on the stereoregurarity. The three blends were immiscible at room temperature, and showed the simple additivity effect in density behavior. The melting point depression with blend composition increased in order of PE(2)/r-EPR>PE(2)/alt-EPR>PE(2)/iso-alt-EPR. In the tensile test, this blend systems have the lowest value or the breaking strength at FE(2) fraction of 0.5. This phenomenon results from the greastest separated phase morphology at this blend composition.