• Elastomers and Composites
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• v.32 no.5
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• pp.325-329
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• 1997

Microbial treatment of the powdered waste tire was studied to recycle the waste tires. Chemoautotrophic acidophilic, iron-oxidizing bacterium was employed to unvulcanize the powdered tires. Biotreated rubber powder was compared to a untreated and a chemically treated powder. The results showed sulfur content of rubber powder(1.33%) were decreased to 1.22% by chemical treatment and 1.12% by microbial treatment for 20 days, 0.88%, for 30 days. One of the problems of the powdered utilization of the waste tires is that rubber powder leads to decrease mechanical properties when it is compounded with other virgin polymers. When tee biotreated powder was compounded with natural rubber, the mechanical properties were less decreased when untreated or chemically treated powder. Therefore, the microbial treatment can be one of useful methods to recycle the waste tire.

• Macromolecular Research
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• v.16 no.5
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• pp.404-410
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• 2008

In order to obtain 'value added products' from polypropylene (PP)/waste ground rubber tire powder (WGRT) composites, PP/WGRT microcellular foams were prepared via supercritical carbon dioxide. The effects of blend composition and processing condition on the cell size, cell density and relative density of PP/WGRT micro-cellular composites were studied. The results indicated that the microcellular structure was dependent on blend composition and processing condition. An increased content of waste ground rubber tire powder (WGRT) and maleic anhydride-grafted styrene-ethylene-butylene-styrene (SEBS-g-MA) reduced the cell size, and raised the cell density and relative density, whereas a higher saturation pressure increased the cell size, and reduced the cell density and relative density. With increasing saturation temperature, the cell size increased and the relative density decreased, whereas the cell density initially increased and then decreased.

• Proceedings of the IEEK Conference
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• 2001.10a
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• pp.220-224
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• 2001

Waste tires are a significant problem with the increasing in number of automobiles. Therefore, many researches have been studied on this field. Recycling is the one of the popular method aspect to environmental and economical in the treatment methods of the waste tire, which loads that the reuse of scrap tire rubber has been a challenge in the past. However, it is not easy method to melt down and mold into new products because the in rubber is a cross-linked polymer. Most difficulty in recycling is the recycled product is not economic. Therefore, the goal of this study is to develop the high valuable products for reused waste tires. In this paper, we try to make an economic recycled technology using scrapped waste tires. This technology may applied for manufacturing the end products such as a rubber block and a ballast mat for high-speed train.

• Elastomers and Composites
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• v.46 no.4
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• pp.318-323
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• 2011

To recycle the waste tire rubber powder, rubber powder composite for waterproof sheet was prepared, and analyzed the effect of the kind of resin and the amount of crosslinking agent on the mechanical property of the composites. The elongation-at-break of the PE composite increased more than 3 times as EPDM was added into rubber composites. As the content of the crosslinking agent increased, the tensile strength of composite increased as well. When recycled polypropylene was used, the increase in composite's tensile strength was more than 3 times. Therefore to use the recycled PP in composite is more effective rather than PP in term mechanical properties.

• Elastomers and Composites
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• v.38 no.2
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• pp.128-138
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• 2003

It goes to be serious with environmental pollution because of great number of waste tires scrapped each you. That is why there are lots of studies for efficient recycle. We tried to reduce particle size of the waste tire powder using a new technology of self-designed grinding machine (SDGM) and ultrasonic treatment. The purpose of this study is to improve the physical properties of reduced waste tire powder. We investigated the fine powder by particle size distribution(PSD) analysis. And also we examined the physical and mechanical properties and cross-link density at various particle sire. Also we carried out morphological studies after making the products by SEM.

• Resources Recycling
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• v.12 no.2
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• pp.28-35
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• 2003

The powder utilization is the one of the best recycling methods for the waste tires. However, economic problem still exist. In order to overcome an economic problem the ground rubber particles are surface modified, which induced to the rubber particles that have good mechanical properties and higher compatibility. In this study, we investigated ultrasonic treatment and reduced rubber particle size. Results showed that sulfur cross-linkage network of the waste rubber is changed by the ultrasonic treatment.

• Computers and Concrete
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• v.10 no.2
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• pp.95-104
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• 2012

This study uses recycled green building materials based on a Taiwan-made recycled mineral admixture (including fly ash, slag, glass sand and rubber powder) as replacements for fine aggregates in concrete and tests the properties of the resulting mixtures. Fine aggregate contents of 5% and 10% were replaced by waste LCD glass sand and waste tire rubber powder, respectively. According to ACI concrete-mixture design, the above materials were mixed into lightweight aggregate concrete at a constant water-to-binder ratio (W/B = 0.4). Hardening (mechanical), non-destructive and durability tests were then performed at curing ages of 7, 28, 56 and 91 days and the engineering properties were studied. The results of these experiments showed that, although they vary with the type of recycling green building material added, the slumps of these admixtures meet design requirements. Lightweight aggregate yields better hardened properties than normal-weight concrete, indicating that green building materials can be successfully applied in lightweight aggregate concrete, enabling an increase in the use of green building materials, the improved utilization of waste resources, and environmental protection. In addition to representing an important part of a "sustainable cycle of development", green building materials represent a beneficial reutilization of waste resources.

• Elastomers and Composites
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• v.41 no.1
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• pp.49-56
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• 2006

The waste tire powder is modified with allylamine in the presence of ultraviolet radiation and the influence of surface modification on the thermal and rheological properties of polypropylene/waste tire powder composites was investigated. X-ray diffraction studies of PP/waste tire powder composite without compatibilizer, such as maleic anhydride-g-polypropylene (MA-PP), shows the increase in peak intensity of ${\beta}$ crystalline peaks, whereas it completely disappears in the presence of the MA-PP. Differential scanning calorimetry results further supported the above fact. The melt viscosities and storage modulus of the composites with modified waste tire powder show higher value than that of composites with unmodified powder and it is attributed to the interaction between amine group on modified powder surface and maleic anhydride of MA-PP.

• Resources Recycling
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• v.23 no.3
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• pp.44-50
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• 2014

In this study, a method of shear crushing and a two-stage disk mill were introduced to grind the waste tire powder. Rubber chips with various size were obtained during the crushing or grinding step. The two-stage disk mill was composed of two drum-type blades rotating at various speed and in opposite directions. Therefore, more roughly surfaced particles of micronized waste tire powder were obtained using shear crushing rather than using conventional cutting crushing. In this study, the shape of shear-crushed waste tire particles was compared with conventional cutting crushing particles by scanning electron microscope. In addition, the particle size analyzer was employed to determine the appropriate particle size of waste ground tire powders obtained in this study.

• Resources Recycling
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• v.24 no.2
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• pp.55-61
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• 2015

In this study, mechanical properties of waste ground rubber tire powder were investigated to evaluate the influence of pre-treatment process for recycling. The tensile test, fracture test and morphology observation were carried out using various kinds of waste ground tire powders, which were produced by grinding and devulcanization process, respectively. As a results, it was found that the produced rubber powder through grinding process increased its tensile strength and elongation with decreasing particle size because of decreasing surface area. Devulcanized rubber powder also increased its tensile strength and elongation by de-crosslink with sulfur. It could be also suggested that devulcanization treatment after grinding process was more efficient recycling process for both increasing tensile property and fracture elongation of waste ground rubber tire powders.