재생 PET섬유의 친수성표면처리에 따른 시멘트 복합재료의 소성수축균열제어 효과

원종필(Won Jong Pil),박찬기(Park Chan Gi),김황희(Kim Hawang Hee),이상우(Lee Sang Woo) 대한토목학회 2007 대한토목학회논문집 A Vol.27 No.3A

본 연구에서는 폐 PET병을 이용하여 만들어진 재생 PET섬유의 친수성처리에 따른 시멘트 복합재료의 소성수축균열제어 효과를 제시하였다. 재생 PET 섬유는 플라스틱섬유로 알려져 있으며 시멘트 복합재료내에서 시멘트 매트릭스와의 부착력이 약하고, 시멘트 매트릭스 내에서 분산성이 빈약한 특성을 가지고 있다. 이와 같은 재생 PET섬유가 소수성재료의 특성을 가지고 있기 때문이다. 본 연구에서는 재생 PET섬유의 표면을 화학적과정을 통하여 친수화처리 하였다. 일반적으로 화학적 처리법은 소수성인 합성섬유의 표면에 OH?, COOH? 또는 무수기를 도입하여 친수성처리를 하는 것이 가장 효과적인 방법으로 알려져 있으며 이와 같은 화학약품으로는 비닐알코올, 알크릴산 및 무수말레인산이 있으며 특히 시멘트 복합재료를 위한 합성섬유의 친수성처리에는 무수말레인산이 널리 사용되어왔다. 본 연구에서는 무수말레인산이 그라프트된 폴리프로필렌(Maleic anhydride grafted polypropylene, mPP)을 이용한 재생 PET 섬유의 친수성처리효과를 소성수축균열제어 실험을 통하여 조사하였다. 실험결과 섬유표면의 친수성처리는 시멘트 복합재료 내에서 분산성과 부착강도를 증가시켜 소성수축균열저항성을 크게 강화하였다. 또한 본 연구의 결과 친수성처리를 한 embossed 형상의 섬유를 체적비로 1.00% 사용하였을 때 시멘트 복합재료의 소성수축균열제어에 가장 효과적이었다. This research presented the effect of hydrophilic treatments of recycled PET fiber made from waste PET bottle on the control of plastic shrinkage cracking of cement based composites. Recycled PET fibers are usually known that plastic fibers have low bond performance and poor dispersion in cement based composites. The reason is the fibers have the characteristics of hydrophobic materials. In this study, the surface of recycled PET fiber was hydrophilized with chemical process. General chemical method which ensures effectiveness is a hydrophilization as inducing anhydro group like OH?, COOH? through vinyl alcohol, acrylic acid, maleic anhydride. Especially, maleic anhydride has been used in hydrophilization of synthetic fiber for cement based composites. In this research, the effect of hydrophilic treatments of recycled PET fiber using maleic anhydride grafted polypropylene(mPP) was examined through plastic shrinkage cracking tests. Test results shows that hydrophilic treatments of fiber surface, the resistance of plastic shrinkage cracking could be highly enhanced due to increased dispersion and bond strength within cement based composites. Also, the results of this study suggests the most effective performance on plastic shrinkage cracking control under condition of embossed type fiber with hydrophilic treatments and 1.00% fiber volume fraction.

재생 폐 PET섬유보강 콘크리트의 부착 및 휨 특성

원종필(Won Jong-Pil),박찬기(Park Chan-Gi),최민정(Choi Min-Jung) 대한토목학회 2008 대한토목학회논문집 A Vol.28 No.3A

본 연구에서는 폐 PET병을 사용하여 구조적으로 효과가 있는 재생 PET섬유를 생산하였고 세 가지 형상의 재생 PET섬유와 시멘트 매트릭스와의 부착성능을 평가하였다. 또한 세 가지 형상의 재생 PET섬유로 보강된 콘크리트의 휨성능 시험을 실시하였다. 시험결과 재생 PEl섬유는 우수한 부착성능의 증가를 보여주었다. 휨시험 결과 재생 PET섬유는 콘크리트의 휨인성을 증가시킨다는 것을 증명하였다. 부착 및 휨시험 결과를 기본으로 요철형 재생 PET섬유의 부착 및 휨성능이 다른 형상의 섬유와 비교하여 가장 우수하였다. This study can be used to produce structurally efficient recycled PET fiber from used waste PET bottles and evaluated the bond performance of the three type of recycled PET fiber and cement matrix. Also, the flexural tests were performed on concrete reinforced using the three type of recycled PET fibers. The test results showed that the recycled PET fiber was significantly increased bond strength. The flexural test results are demonstrated that recycled PET fibers improved the flexural toughness of concrete. Based on the bond and flexural test results, the bond and flexural performance of embossed type recycled PET fibers were significantly better than those of the other shape fibers.

Recycling practice and targets of PET bottles by EPR towards a circular economy in South Korea

( Youngsun Kwon ),( Byeonghwan Kim ),( Yong-chul Jang ),( Hakyun Song ),( Kyunghoon Choi ),( Dong Gyu Shin ),( Yongseon Lee ) 한국폐기물자원순환학회 2022 ISSE 초록집 Vol.2022 No.-

Polyethylene terephthalate (PET) is one of the commonly used plastic packaging materials. Improper disposal of PET bottles may create plastic pollution in oceans and rivers and streams. In Korea, the collection and recycling of used PET bottles has been managed by Extended Producer Responsibility (EPR) system since 2003. In this study, material flow analysis for PET bottles was carried out to elucidate its quantitative flow for collection and recycling. Also, based on the analysis, in 2018, approximately 236 thousand tons of used PET bottles were recycled, while only 30 thousand tons were used as high-grade recycled materials (sheet and bottles), and about 206 thousand tons were used as low-grade recycled materials (e.g., fiber, strings). It is expected that more than 500,000 ton of PET bottles will be consumed in 2030 with an assumption 5% annual increase. In order to accelerate high-quality PET recycling, mandatory recycled content of PET bottles would be required in the future, as many EU countries are adopting the requirement. As a result of greenhouse gas reduction using WARM, in 2030, more than 373,000 ton CO₂eq could be reduced with the assumption of 30% recycled content use in PET bottles. This study proved the potential benefits of PET bottle recycling by providing the amount of greenhouse gas reduction as well as material recycling toward a circular economy in South Korea.

화학재생 폴리에스터 칩의 물성향상 연구

임대희,오미옥,최연주,김성훈,Lim, Dae Hee,Oh, Mi Ok,Choi, Yeon Joo,Kim, Seong Hun 한국섬유공학회 2013 한국섬유공학회지 Vol.50 No.2

Chemically recycled/virgin poly(ethylene terephthalate) (PET) blends were prepared by melt blending to improve the physical properties of the chemically recycled PET. The effect of virgin PET on the mechanical and thermal properties, molecular weight, and crystallinity of the chemically recycled/virgin PET blends was investigated. The tensile strength and modulus of the chemically recycled/virgin PET blends increased with increasing virgin PET content. The crystallinity of the chemically recycled/virgin PET blends depended significantly on the recycled PET content because of the nucleation effect of the residual catalyst generated from the depolymerization of PET. The color index of the chemically recycled/virgin PET blends was also investigated to determine the color of the blends numerically.

순환경제를 위한 PET병 물질흐름분석과 재활용에 따른 온실가스 감축량 산정 연구

임진홍 ( Jin Hong Im ),장용철 ( Yong-chul Jang ) 한국폐기물자원순환학회 2021 한국폐기물자원순환학회지 Vol.38 No.4

Plastic wastes are majorly packaging plastic materials composed of polyethylene terephthalate (PET). The improper disposal of PET bottles can cause severe environmental problems, such as environmental plastic pollution, greenhouse gas emission, resource depletion, and marine plastic pollution. Owing to the steady increase in the consumption of PET bottles, it is important to improve the recycling rates and quality of recycled PET products. This study analyzed the material flow of PET bottles in Korea in 2018 to develop an appropriate management policy for recycling PET bottles. In addition, the content of greenhouse gases reduced via the recycling of PET bottles was quantified using US EPA waste reduction model (WARM). The results revealed that approximately 301,000 tons of PET bottles were sold and discharged as plastic waste in 2018. In addition, approximately 236,000 tons of waste PET bottles were recycled. Consequently, about 240,000 tons of CO₂eq was reduced in 2018 and 1,768 thousand tons of CO₂eq was reduced from 2010 to 2018. This study aimed to highlight the potential benefits of recycling PET bottles by providing the content of reduced greenhouse gas and recycled materials. The quantitative analysis of the material flow revealed that it is essential to perform high-quality recycling of PET bottles (e.g., bottle-to-bottle and long-fiber uses) in contrast to low-grade recycling to achieve a circular economy.

재생 PET 섬유의 형상 및 길이가 시멘트 복합재료의 소성수축균열에 미치는 영향

원종필,박찬기,김황희,이상우 한국콘크리트학회 2007 콘크리트학회논문집 Vol.19 No.2

본 연구의 주요목적은 시멘트 복합재료의 소성수축균열제어에 폐 PET병으로부터 만들어진 재생 PET섬유의 효과를 평가하는 것이다. PET은 플라스틱재료라 알려진 재료로 음료수 병 등에 다양하게 적용되어 왔다. 그렇지만 폐 PET병은 사용 후에 환경적 측면에서 큰 문제점으로 부각되고 있다. 따라서 폐 PET 병을 재활용하는 방법에 대한연구는 환경 및 경제적 측면에서 중요하게 되었다. 폐 PET병을 재활용하는 방법 중 시멘트 보합재료의 보강섬유로 사용하는 방법은 효과적인 방법 중에 하나이다. 본 연구에서는 시멘트 복합재료의 소성수축균열에 재생 PET 섬유의 형상 및 길이의 효과를 얄은 슬래브실험을 통해서 조사하였다. 실험계획은 섬유의 형상, 길이 및 혼입률의 영향을 이해하기 위하여 수행하였다. 재생 PET 섬유의 형상은 straight, crimped 및 embossed type의 3가지 형상을 포함하며, 각 3가지 섬유형상 마다 3가지 수준의 섬유 혼입률 및 2가지 종류의 섬유 길이에 대해서 조사하였다. 실험 결과 재생 PET 섬유는 시멘트 복합재료의 소성수축균열에 효과적이었다. 섬유의 길이의 관점에서 길이가 긴 섬유는 섬유의 형상이 동일할 때 섬유체적비가 적을 때 효과적이며, 섬유체적비가 증가하면 길이가 짤은 섬유가 더욱더 효과적이었다. 또한 embossed type의 섬유는 적은 섬유 혼입률에서 다른 형상의 섬유보다 소성수축균열제어 효과가 우수하였으며, 높은 섬유 혼입률에서는 straight type의 섬유가 다른 형상의 섬유보다 시멘트 복합재료의 소성수축균열제어에 가장 효과적이었다.

Cu, Mn/γ-Al₂O₃ 촉매상에서 polyethylene telephthalate 단량체의 회수 연구

심재욱 ( Jae-wook Sim ),김승수 ( Seung-soo Kim ) 한국공업화학회 2017 공업화학 Vol.28 No.4

Polyethylene terephthalate (PET)는 화학적 안정성과 높은 기계적 강도를 가지고 있어 식품, 의류 등 다양한 분야에서 사용되고 있으며, 이로 인해 PET는 주요 폐플라스틱 폐기물 중 하나이다. 본 연구에서 PET를 재활용하기 위해 ethyl-ene glycol (EG)와 glycolysis의 반응을 이용하여 단량체 회수에 관한 연구를 수행하였다. 마이크로 튜빙 반응기를 사용하여 EG/PET비율 1∼4, 반응시간 15∼90 min, 반응온도 250∼325 ℃에서 망간, 구리 촉매 조건하에서 연구를 진행하였다. 10 wt% Cu/γ-Al₂O₃ 촉매에서 반응온도, 시간과 EG/PET의 비가 각각 300 ℃, 30 min와 1 : 2였을 때 가장 높은 89.46%의 bis (2-hydroxyethyl) terephthalate monomer (BHET) 수율을 나타내었다. Polyethylene terephthalate (PET) has been widely applied in polymers and packaging industries to produce synthetic fibers, films, drink bottles or food containers. Therefore, it has become one of the major plastic wastes. In this article, glycolysis known as one of the main methods in PET chemical recycling was investigated using a glycol to break down the polymer into a monomer. Glycolysis of PET and ethylene glycol was performed in a micro-tubing reactor under various conditions. The effect of glycolysis conditions on the product distribution was investigated at experimental conditions of the EG/PET ratio of 1∼4, the reaction time of 15~90 min and the reaction temperature of 250∼325 ℃ with Mn and Cu catalysts. The highest yield of bis (2-hydroxyethyl) terephthalate monomer (BHET) was obtained as 89.46 wt% under the condition of the reaction temperature of 300 ℃ and the time of 30 min using 10 wt% Cu/γ-Al₂O₃ catalyst, with the PET and ethylene glycol ratio of 1 : 2.

PET분해효소(PETase) 과발현 전세포 촉매의 해양미세플라스틱 생분해 활성 연구

김현지,임성인,박종하,박애란,이대희,전준호,권혁택 (사)한국해양바이오학회 2022 한국해양바이오학회지 Vol.14 No.2

The increased production and consumption of polyethylene terephthalate (PET)-based products over the past several decades has resulted in the discharge of countless tons of PET waste into the marine environment. PET microparticles resulting from the physical erosion of general PET wastes end up in the ocean and pose a threat to the marine biosphere and human health, necessitating the development of new technologies for recycling and upcycling. Notably, enzyme-mediated PET degradation is an appealing option due to its eco-friendly and energy-saving characteristics. PETase, a PET-hydrolyzing enzyme originating from Ideonella sakaiensis, is one of the most thoroughly researched biological catalysts. However, the industrial application of PETase-mediated PET recycling is limited due to the low stability and poor reusability of the enzyme. Here we developed the whole-cell catalyst (WCC) in which functional PETase is attached to the outer membrane of Escherichia coli. Immunoassays are used to identify the surface-expressed PETase, and we demonstrated that the WCC degraded PET microparticles most efficiently at 30°C and pH 9 without agitation. Furthermore, the WCC increased the PET-degrading activity in a concentration-dependent manner, surpassing the limited activity of soluble PETase above 100 nM. Finally, we demonstrated that the WCC could be recycled up to three times.

Cu, Mn/γ-Al₂O₃ 촉매상에서 polyethylene telephthalate 단량체의 회수 연구

심재욱,김승수,Sim, Jae-Wook,Kim, Seung-Soo 한국공업화학회 2017 공업화학 Vol.28 No.4

Polyethylene terephthalate (PET)는 화학적 안정성과 높은 기계적 강도를 가지고 있어 식품, 의류 등 다양한 분야에서 사용되고 있으며, 이로 인해 PET는 주요 폐플라스틱 폐기물 중 하나이다. 본 연구에서 PET를 재활용하기 위해 ethylene glycol (EG)와 glycolysis의 반응을 이용하여 단량체 회수에 관한 연구를 수행하였다. 마이크로 튜빙 반응기를 사용하여 EG/PET비율 1~4, 반응시간 15~90 min, 반응온도 $250{\sim}325^{\circ}C$에서 망간, 구리 촉매 조건하에서 연구를 진행하였다. 10 wt% $Cu/{\gamma}-Al_2O_3$ 촉매에서 반응온도, 시간과 EG/PET의 비가 각각 $300^{\circ}C$, 30 min와 1 : 2였을 때 가장 높은 89.46%의 bis (2-hydroxyethyl) terephthalate monomer (BHET) 수율을 나타내었다. Polyethylene terephthalate (PET) has been widely applied in polymers and packaging industries to produce synthetic fibers, films, drink bottles or food containers. Therefore, it has become one of the major plastic wastes. In this article, glycolysis known as one of the main methods in PET chemical recycling was investigated using a glycol to break down the polymer into a monomer. Glycolysis of PET and ethylene glycol was performed in a micro-tubing reactor under various conditions. The effect of glycolysis conditions on the product distribution was investigated at experimental conditions of the EG/PET ratio of 1~4, the reaction time of 15~90 min and the reaction temperature of $250{\sim}325^{\circ}C$ with Mn and Cu catalysts. The highest yield of bis (2-hydroxyethyl) terephthalate monomer (BHET) was obtained as 89.46 wt% under the condition of the reaction temperature of $300^{\circ}C$ and the time of 30 min using 10 wt% $Cu/{\gamma}-Al_2O_3$ catalyst, with the PET and ethylene glycol ratio of 1 : 2.

재활용 PET 투수블록과 시멘트 투수블록의 환경영향 비교평가에 관한 연구

임성현 ( Sung-hyun Lim ),윤석표 ( Seok-pyo Yoon ) 한국폐기물자원순환학회 2021 한국폐기물자원순환학회지 Vol.38 No.4

In this study, we developed an environmental assessment method to investigate permeable blocks prepared using recycled polyethylene terephthalate (PET) as a binder. First, Los Angeles abrasion test was conducted to simulate the surface abrasion caused by the long-term use of water-permeable block, and the number of rotations was 100-300. To separate the microplastics from the residual fragments of the degraded surface of the permeable block, the microplastics were subjected to a flotation process using calcium chloride as a sorting solvent. The obtained microplastics from the abrasion test was quantitatively and qualitatively analyzed using a particle size analyzer, microscopy, and Fourier transform-infrared spectroscopy. To obtain the extract, the permeable block was subjected to a leaching test, and the pH and Ca concentration were measured. The pH of the cement-based permeable block (10.79 ± 0.17) was higher than that of the PET-based permeable block (9.58 ± 0.23). In addition, the extracts of recycled PET- and cement-based permeable blocks were subjected to an acute toxicity test using Daphnia, and the results revealed that the toxic unit of the recycled PET permeable blocks was 0, whereas that of the cement-based permeable blocks was 1.98 ± 0.11.