• Journal of the Korean Applied Science and Technology
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• v.30 no.4
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• pp.701-714
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• 2013

Recently, due to the activation policy of biodiesel, the blending biodiesel to petroleum product is increasing. Low-temperature fluidity and oxidation stability are the most significant issues to the marketers and end users of biodiesel. Thus, the way to control the quality of biodiesel blended fuels was investigated by duplicating the real storage situation of biodiesel blended fuels and evaluating the effect of oxidation trend and quality degradation. From the results of oxidation degradation test of biodiesel blended fuels, no special quality degradation has been observed through the evaporation for 18 weeks in a summer season under a storage circumstance without exposure to the sun light. However, the severe quality degradation was observed in PE vessel in only 2 weeks of storage. This oxidation degradation was also verified with FT-IR spectrum change. However, the special symptom cannot be distinguished by the quality test because the quality specifications were satisfied despite of the drastic oxidation degradation. Namely, the problem in a vehicle could be occurred by oxidation materials(polymer, organic acid. etc.) under oxidation even though it satisfied the quality specification.

• Korean journal of applied entomology
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• v.46 no.2
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• pp.325-330
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• 2007

Among various food base baiting materials, beer and macerated cucumber were the most effective to induce slug that is a troublesome pest on leafy vegetables, especially on lettuce. However, the baits attracted only but did not kill the pest. When the baits were combined with various insecticidal organic materials, a few combinations such as beer and cigarette mixture successfully induced and killed the slug in the field test. The most effective combination of beer 50ml and a cigarette contained in a small plastic box killed 25 slugs per night. While macerated cucumber 50ml and a cigarette mixture killed only 4.3 slugs. The bait of beer and cigarette mixture revealed 68.4% control value against slug damage when treated for 3 consecutive days in a lettuce cultivation greenhouse. The bait also effectively reduced the slug damage in a lettuce nursery showing 58.3% control value. The method seemed highly useful for the control of slug in the organic farming system in which application of pesticides are strictly prohibited.

• Resources Recycling
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• v.12 no.4
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• pp.58-64
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• 2003

A study on the preparation of RDF with ASR materials from shredder line of end-of-life vehicles has been peformed by using hot molding method. ASR materials used in the work were plastics, fibers and sponge which were cut by less than 10 mm in size prior to hot molding and 40, 60 and 80 mm mold in diameter were employed for RDF forming. It was found that heating temperature, heating time and mixing ratio of materials played an important role in the hot molding of ASR materials. Density of RDF samples Prepared in the work was in the range of 0.5∼0.9gr/ml depending on the hot molding conditions and it was decreased with increase in the content of sponge. Breaking strength of RDF samples was observed to 0.8∼3.0MPa and it was also increased with increase in density of RDF samples. Finally, when heating temperature was elevated, density of RDF was increased due to Increase in molten part of ASR materials which resulted in the enhancement of breaking strength of RDF.

• Resources Recycling
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• v.23 no.4
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• pp.30-36
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• 2014

300,000 tons of waste tires are annually being produced with development of the automotive industry in Korea. Landfill and incineration treatment system are causing the economic problem through secondary environmental pollution and waste. Therefore, as one of the ways to take advantage of this, Thermo-Plastic Vulcanized (TPV) composite was prepared by the ground waste tire and plastic powders. The waste tire powder was gained by mechanical fracturing through crushers. The waste tire powder was ground by a shear crushing method and a 2-stage disk mill method instead of cutting crushing one. The waste tire powder of 50 mesh was mixed with Polypropylene(PP) in various proportions. TPVs were prepared by an extrusion, and tensile and impact tests were performed. In addition, the same experiments were repeated in 40, 80, 140 mesh conditions in order to observe size effect of waste tire powders.

• Clean Technology
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• v.15 no.3
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• pp.186-193
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• 2009

The characteristics of product materials obtained from thermal degradation of low-qualify pyrolytic oil were investigated in this study. The reactants were produced by pyrolysis of mixed plastic waste with film type in a commercial rotary kiln reaction system. The properties of reactants were measured by elemental analysis, calorimetry analysis and SIMDIST analyst. The result of degradation experiments with different reaction temperature programs was discussed through product yields, cumulative yields and production rates of oil products. The multi-step reaction temperature program resulted in higher yields of product oils and lower yields of residues than one-step reaction temperature program. The product characteristics such as production yield and the rate of oil products etc. were influenced by reaction temperature program in the continuous thermal degradation.

• Applied Chemistry for Engineering
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• v.35 no.4
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• pp.273-283
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• 2024

As the adverse environmental impacts due to plastic waste become more severe, there is an increasing demand for developing a sustainable ecosystem using biodegradable polymers. Biodegradable polymers are those that can be biochemically decomposed through the enzymatic activity of microorganisms. Currently, a variety of biodegradable polymers with varying properties is being investigated. In particular, polymer blends with an aim to control the biodegradation rate and mechanical properties are under active research. The biodegradable polymer industry, which has not yet reached economies of scale, does not have a cost advantage compared to petroleum-derived polymers. To overcome this challenge, there is an urgent need to expand its application fields to various high-value industries (separators, electronic materials, and medical fields). This review summarizes the current state-of-the-art biodegradable polymers, polymer blends, and recent research trends in new niche applications.

• Journal of the Korean Wood Science and Technology
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• v.27 no.3
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• pp.51-62
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• 1999

The objective of this research is to develop paper sludge reinforced thermoplastic composites which incorporate the advantages of each component materials. The effects of paper sludge content(0, 10, 20, 30, 40----), mesh size(20~40, 60~80, less than 100mesh), and coupling agent(Epolene E-43 and Epolene G-3003) on the mechanical properties of paper sludge-polypropylene composites were investigated. Composite density increased with an increase in the paper sludge content. When paper sludge is incorporated into a polypropylene matrix, the flexural properties of the composite increase significantly with an increase in the paper sludge mixing ratio. Especially, flexural modulus was improved with increasing paper sludge content. The flexural strength of composites was improved, but flexural modulus reduced somewhat with decreasing paper sludge particle size. The flexural properties of paper sludge-polypropylene composites were improved by using coupling agents to enhance the bonding between reinforcing filler and matrix. Use of the epolene E-43 and G-3003 resulted in considerable improvement in the flexural strength over control specimens. The flexural strength of the G-3003 composite system is higher than that of the E-43 system. Generally, izod notched impact strength of paper sludge-polypropylene composite decreased slightly, whereas izod unnotched impact strength decreased significantly with increasing paper sludge contents. There was no effects of paper sludge particle size on impact strength of paper sludge-polypropylene composites. And izod unnotched impact strength of epolene E-43 composite system sharply decreased but that of G-3003 composite system was no tendency with increasing additive content.

• Journal of the Korean Chemical Society
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• v.54 no.1
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• pp.137-141
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• 2010

Generally, polymer materials are not air-permeable and hydrophilic. In addition, they do not possess anti-fungal property. Hydrophilicity, air-permeability, and anti-fungal properties of new composites consisting of polymer, ceramic nanoparticles, and silver ion were investigated by contact angle measurements, air permeation time, and cell culture. The hydrophilic, air-permeable, and anti-fungal composites can be used in health care industry.

• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.321-324
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• 2009

Upgrading of pyrolysis wax oil has been conducted in a continuous fixed bed reactor at $450^{\circ}C$, 1hour, LHSV 3.5/h. The catalytic degradation using HZSM-5 catalyst are compared with the thermal degradation and also was studied with a function of experimental variables. The raw pyrolysis wax oil shows relatively high boiling point distribution ranging from around $300^{\circ}C$ to $550^{\circ}C$, which has considerably higher boiling point distribution than that of commercial diesel. The product characteristic from thermal degradation shows a similar trend with that of raw pyrolysis wax oil. This means the thermal degradation of pyrolysis wax oil at high degradation temperature is not sufficiently occurred. On the other hand, the catalytic degradation using HZSM-5 catalyst relative to the thermal degradation shows the high conversion of pyrolysis wax oil to light hydrocarbons. This liquid product shows high gasoline range fraction as around 90% fraction and considerably high aromatic fraction in liquid product. Also, in the catalytic degradation the experimental variable such as catalyst amount and reaction temperature was studied.

• Fire Science and Engineering
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• v.19 no.4 s.60
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• pp.87-92
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• 2005

The PASCON of the flame resistance and the economic feasibility was prepared by non-halogenate flame retardant system. Prepared PASCON samples contained various flame retardants were subjected to flame tests(KS M 3015). We have studied that the effect of various flame retardants on the inflammability of PASCON and the effect of synergist on the flame resistance. As results, PASCON contained red-phosphorus as flame retardant exhibited excel lent flame retardancy. Also, the improvement of flame resistance is achieved by addition of 2.5phr synergist in the red-phosphorus(RP)/magnesium hydroxide(MH) system.