• Korean Chemical Engineering Research
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• v.52 no.1
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• pp.17-25
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• 2014

Wide spread application and non-biodegradability of the poly(ethylene terephthalate) generate a huge amount of waste and disposal, posing serious environmental problems. Disposal of the PET wastes also can be thought as an economic loss of valuable chemical resources. We present various ways of feedstock recycling of PET waste to deal with environmental and economic problems. Feedstock recycling is one of promising technologies. It is based on the concept of depolymerizing the condensation polymer such as PET through solvolytic chain cleavage into low molecular products which can be purified and reused as raw materials for the production of high quality chemical products.

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2003.05a
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• pp.418-421
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• 2003

경량ㆍ고강도 기능성 Composite는 경량구조재료로 차량, 항공기, 선박 및 각종 설비의 안전구조재로 그 용도가 다양하게 사용되고 있다. 특히 폐플라스틱을 이용한 경량구 조재는 가격 경쟁력이 높고 또한 환경 및 자원 재활용 측면에서 관심이 고조되고 있다. 고강도, 안전성 확보를 위해 사용가능한 폐플라스틱 소재로는 가공성이 용이한 폐Polyethylene(PE), 폐Polypropylene(PP), 폐Polyethyleneterephthalate(PET) 등을 주원료로 가공되나, 기계적 특성이 저하되어 이의 개선을 위해 여러 가지 형태의 충진재의 혼합을 통해 개선하고자 하는 연구가 진행되어 왔다.(중략)

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2002.11a
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• pp.185-186
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• 2002

폐 플라스틱은 석유 물질인 탄화수소로 구성하고 있지만 효과적으로 재활용되지 못하고 대부분 매립, 소각 등의 방법으로 처리하고 있다. 플라스틱은 다양한 용도로 사용되기 때문에 플라스틱의 이용과 소비의 증가는 필연적이다. 예로 미국 가정의 폐 플라스틱은 63% 폴리에틸렌, 11% 폴리프로필렌, 11% 폴리스타이렌, 7% PET 그리고 7% PVC가 발생되는데 이들 화합물 구조가 포화탄화수소형이기 때문에 70% 정도가 방향족 화합물인 석탄에 비해 수소첨가 반응이 요구되지 않는다.(중략)

• Journal of the Korea Concrete Institute
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• v.16 no.4 s.82
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• pp.521-528
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• 2004

In general, polymer concrete has more excellent mechanical properties and durability than Portland cement concrete, but very sensitive to heat and has large deformations. In this study, the long-term creep behaviors was predicted by the short-term creep test, and then the characteristic of creep of recycled-PET polymer concrete was defined by material and experimental variables. The error in the predicted long-term creep values is less than 5 percent for all polymer concrete systems. The filler carry out an important role to restrict the creep strains of recycled PET Polymer concrete. The creep strain and specific on using the $CaCO_3$ were less than using fly-ash. The creep increases with an increase in the applied stress, but not proportional the rate of stress increase ratio. The creep behavior of polymer concrete using recycled polyester resin is not a linear viscoelastic behavior.

• Journal of the Korea Concrete Institute
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• v.17 no.4 s.88
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• pp.499-504
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• 2005

Polymer concrete shows excellent mechanical properties and chemical resistance compared with conventional normal cement concrete. The polymer concrete Is drawing a strong interest as high-performance materials in the construction industry Resins using recycled PET offer the possibility of a lower source cost of materials for making useful polymer concrete products. Also the recycling of PET in polymer concrete would help solve some of the solid waste problems Posed by plastics and save energy. An objective of this paper is to estimate the damage of sulfuric acid, through investigating recycled PET polymer concrete, immersed at sulfuric acid solution for 84 days. As a result of testing, recycled PET PC, used $CaCO_3$ as filler, makes a problem of appearance and strength if they are exposed for long term at corrosion environment. On the other hand, recycled PET PC, used fly-ash as filler, had less effect on decrease in weight and strength. Recycled PET PC is excellent chemical resistance, resulting in the role of unsaturated polyester resin which consists of polymer chain structure accomplishes bond of aggregates and filler strongly. Also, recycled PET PC, used fly-ash as filler, is stronger resistance of sulfuric acid corrosion than $CaCO_3$, because it is composed of $SiO_2$ and very strong glassy crystal structure. Therefore, recycled PET PC, used fly-ash as filler, is available under corrosion circumstances like sewer pipe or waste disposal plant.

• Journal of the Korea Concrete Institute
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• v.17 no.3 s.87
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• pp.335-342
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• 2005

In this paper, fundamental properties of Polymer Concrete(PC), made from unsaturated polyester resin based on recycled PET and recycled aggregate were investigated. Mechanical properties include strength, modulus of elasticity, and chemical resistance. Resins based on recycled PET and recycled aggregate offer the possibility of low source cost for forming useful products, and would also help alleviate an environmental problem and save energy. The results of test for resin contents and recycled aggregate ratio we, first, the strength of Polymer Concrete made with resin based on recycled PET and recycled aggregate increases with resin contents relatively, however beyond a certain resin contents the strength does not change appreciably, Second, the relationship between the compressive strength and recycled aggregate ratio at resin $9\%$ has a close correlation linearly whereas there is no correlation between the compressive strength and the flexural strength of RPC with recycled aggregate ratio. Third, the effect of acid resistance at resin $9\%$ was found to be nearly unaffected by HCI, whereas the PC with $100\%$ recycled aggregate showed poor acid resistance. Unlike acid, alkali nearly does not seem to attack the RPC as is evident from the weight change and compressive strength. And last, In case of stress-strain curve of polymer concrete with $100\%$ of natural aggregate and $100\%$ recycled aggregate it is observed the exceptional behavior resulting in different failure mechanisms of the material under compression.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.797-800
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• 2008

To decrease the usage of cement, the pozzolan reaction materials are used as a mineral admixture. Hwang Toh which is broadly deposited in Korea is well known as a environment friendly material and the activated Hwang Toh which has the property of pozzolan reaction is practically used as a mineral admixture of concrete. PET fiber which is made by recycled PET bottle controls micro crack in concrete. But the study about concrete mixed with reinforcing fiber is not enough and the property of Hwang Toh concrete mixed with PET fiber is more complicated case. So this study performed drying shrinkage experiment to analyse mechanical property of Hwang Toh concrete mixed with PET fiber.

• Proceedings of the Korea Concrete Institute Conference
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• 2002.05a
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• pp.631-636
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• 2002

This study shows basic data for using as the structural lightweight aggregate. This will be the procedural method of recycling environmental close waste PET bottle lightweight aggregate(PBLA) that is rapidly increased the amount of production of waste PET bottle recently, the quality of developed PBLA and the fundamental properties by analyzing of mortar containing with PBLA. After experiment, the result shows the PBLA quality that have oven dry specific gravity of 1.39, unit volume weight of 844 kg/m$^3$ and absorption rate of 0% is satisfied with qualify regulation of lightweight aggregate. The flowability of mortar containing PBLA is increased maximum 16% with increasing mixing ratio of PBLA, however the compressive strength of mortar is decreased maximum 35% with increasing mixing ratio of PBLA.

• Resources Recycling
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• v.18 no.2
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• pp.30-38
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• 2009

In this research, we studied the scale-up triboelectrostatic process for separation of PVC from higher gravity fraction of plastic wastes produced from wet gravity separation process. High density polyethylene (HDPE) was found to be the most effective materials for a tribo-charger in the separation of plastic tailings. In a commercial scale triboelelctrostatic separator unit, using the HDPE pipe-line charger, a grade of 99.1% with PET, PS and others and a recovery of 86% was obtained under optimum conditions at over 250 kV/m electric field, a splitter position of -8 cm from the center, and less than 40% relative humidity. The developed unit can process the plastic wastes at a 300 kg/h, and the product can be utilized as RPF or RDF of over grade 2.

• Journal of the Korea Concrete Institute
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• v.16 no.1 s.79
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• pp.79-87
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• 2004

The qualify of lightweight aggregate made from waste PET bottle(WPLA) and the workability, the unit weight and strength property of concrete with WPLA were investigated for the purpose of recycling the waste PET bottles as lightweight concrete fine aggregate. This study indicated a good result that WPLA should be replaced with less than $50\%$ of natural fine aggregate. When WPLA was replaced with $50\%$ of natural fine aggregate, the specific gravity and water absorption of mixed fine aggregate were greatly reduced about 23 and $75\%$ respectively in comparison with those of river sand. The quality of WPLA affected on the properties of lightweight aggregate concrete. The workability of fresh concrete with WPLA(WPLAC) was improved with increasing the replacement ratio of WPLA and water cement ratio. Slump increasing ratio of the former showed about $45 {\~} 120\%$ because that a specific gravity of fine aggregate was decreased from 2.6 to 1.7. The unit weight of concrete with $75\%$ WPLA was decreased about $17\%$ in comparison with that of control concrete. Furthermore, the compressive strength of concrete with 25 and $50 \%$ WPLA at the age of 28 days increased higher than 30 MPa regardless with water cement ratio (W/C=45, 49 and $53\%$) of this study. Specific strength of concrete with $25\%$ WPLA, $15.11{\times}10^3 MPa{\cdot}m^3/kg$, was higher than that of contro concrete in water cement ratio of $49\%$. The compressive strength-splitting tensile strength ratio and compressive strength-modulus of elasticity ratio of WPLAC were similar to that of nomal lightweight aggregate concrete. This results showed a good estimation that WPLA will be able to recycled as a fine aggregate for lightweight concrete.