셀룰로오스 아세테이트/폴리에틸렌글리콜(PEG600)에 대한 폴리에틸렌글리콜(PEG200), 트리아세틴(TA)의 가소화 효과 및 기계적 물성

김상구(Sang Gu Kim),김기홍(Gi Hong Kim),김도영(Do Young Kim),서관호(Kwan Ho Seo) 한국고분자학회 2017 폴리머 Vol.41 No.2

본 연구에서는 셀룰로오스 아세테이트(CA)/폴리에틸렌글리콜(PEG600)의 가소화 한계를 살펴보고 폴리에틸렌글리콜(PEG200), 트리아세틴(TA)을 각각 도입하여 가소화 효과를 향상하고자 하였다. CA/PEG600/PEG200, CA/PEG600/TA는 Tg의 감소가 약 150℃에서 각각 132℃, 145℃로 가소화 효과의 향상을 확인하였다. 특히 CA/PEG600/PEG200은 CA/PEG600/TA보다 혼화성이 좋은 것을 확인하였다. CA/PEG600/PEG200은 용융 흐름성을 증가시키지만 CA/PEG600/TA는 오히려 감소시키는 것을 확인하였다. CA/PEG600/PEG200은 CA/PEG600에 비해 인장강도 및 신장률 모두 증가하지만 CA/PEG600/TA는 인장강도의 증가만을 확인하였다. 또한 이축 압출기를 통한 CA/PEG600의 가소화 영향은 기존 실험보다 상대적으로 감소하는 것을 확인하였다. In this study, cellulose acetate (CA)/polyethylene glycol (PEG600) were investigated for the limitation of the plasticizing. Then, polyethylene glycol (PEG200) and triacetin (TA) were respectively introduced to improve the plasticizing effect. As a result, CA/PEG600/PEG200, CA/PEG600/TA confirmed an increase in the plasticizing effect by decreasing the Tg from about 150 ℃ to 132 ℃, and 145 ℃. In particular, CA/PEG600/PEG200 had better miscibility than CA/PEG600/TA. It was also found that the melt flow of CA/PEG600/PEG200 was increased but CA/PEG600/TA was decreased. CA/PEG600/PEG200 was increased both tensile strength and elongation compared to CA/PEG600, while CA/PEG600/TA indicated only an increase in tensile strength. The influences of twin-screw extruder were confirmed that plasticizing effect relatively decreased to compare the conventional experiment.

Numerical Simulation on the Enhanced Mixing of Polymer Melt by Single Screw with Torsion Elements in the Homogenizing Section

Ranran Jian,Weimin Yang,Lisheng Cheng,Pengcheng Xie 한국고분자학회 2018 폴리머 Vol.42 No.6

As one of key factors that determine the quality of products, the homogenization of polymer melt is closely dependent on the mixing of polymers. The mixing of polymer melt in the homogenizing section by a single screw with torsion elements was analyzed with the computational fluid dynamics (CFD) simulation. The simulation results reveal that screws with such torsion elements arranged in a decentralized form have smaller segregation scale, distribution index and higher mixing efficiency, compared with the conventional screw. The decentralized arrangement is more effective for mixing than the centralized distribution. The rotational flow induced by the torsion elements can significantly enhance the mass transfer process and improve mixing and plasticizing. Compared with those in conventional screw, the distributions of temperature and viscosity are more uniform at the outlet of torsion screws, which also made the torsion element generally more effective and efficient for mixing and plasticizing.

A strategy to prepare internally plasticized PVC using a castor oil based derivative

Hongying Chu,Jinju Ma 한국화학공학회 2018 Korean Journal of Chemical Engineering Vol.35 No.11

Internally plasticized PVC was prepared via chemical reaction of azide PVC and alkynyl group containing castor oil methyl ester. The chemical structure of alkynyl group containing castor oil methyl ester and internally plasticized PVC was characterized with FT-IR and 1H NMR. Properties of internally plasticized PVC, including thermal stability, tensile tests and resistance to extraction in different solvents, was investigated. The results showed that alkynyl group containing castor oil methyl ester, as internal plasticizer of PVC, not only decreased the Tg of PVC from 84.6oC to 41.6oC efficiently, but also presented no plasticizer loss in five different solvents. The tensile tests showed that elongation at break and tensile strength of internally plasticized PVC was 353.8% and 18.1MPa. The internally plasticized PVC has potential application in replacing the traditional PVC material in PVC products with high durability.

Process modeling and optimization studies of high pressure membrane separation of CO2 from natural gas

ABDUL LATIF AHMAD,Jimoh Kayode Adewole 한국화학공학회 2016 Korean Journal of Chemical Engineering Vol.33 No.10

Process design and optimization methodology for high pressure membrane removal of CO2 from natural gas was developed. An approximate model based on plasticization pressure and permeability parameters at plasticization was proposed for quick evaluation of membrane materials for the high pressure operation. The model was derived by applying the partial immobilization assumption to the fundamental model of solution - diffusion mechanism along with a modified upper-bound curve. About ninety membranes obtained from literature were used to illustrate this methodology. The best three were selected for detailed process modeling and optimization. Process optimization was achieved via non-linear programming constraint optimization model. Gas processing cost was used as the objective function, while plasticization pressure and the CO2 concentration in the feed were used as the constraints. Membrane of 6FDA-durene had the lowest annual gas processing cost while 6FDA-DAM : DABA 2 : 1 had the highest optimum product purity.

사출 성형의 가소화 과정의 공기유입에 관한 연구

이병옥(B. O. Rhee),박호근(H. G. Park),김봉주(B. J. Kim) 한국생산제조학회 2017 한국생산제조시스템학회 학술발표대회 논문집 Vol.2017 No.4

PMMA 전용 가소화 스크류 개발

현창훈(C.H. Hyun),신현철(H.C. Shin),박경호(K.H. Park),유성철(S.C. Yoo) 한국생산제조학회 2012 한국생산제조시스템학회 학술발표대회 논문집 Vol.2012 No.4

Microfabrication and mycelial-based leather production from mushrooms.

Jegadeesh Raman,Da-Song Kim,Hyun-Jae Shin 한국버섯학회 2021 버섯 Vol.25 No.2

복합재료 전처리 온도에 따른 유리전이온도 분석

손진혁(Jin-Hyeok Son),임준선(Jun-Seon Lim),조성인(Sung-In Cho) 항공우주시스템공학회 2023 항공우주시스템공학회 학술대회 발표집 Vol.2023 No.05

산업디자인을 위한 플라스틱 소재 활용 가이드 - 지속 가능한 디자인의 관점에서 -

오세헌 한국디자인트렌드학회 2020 한국디자인포럼 Vol.25 No.4

Background Plastic is one of the most essential materials used in the industrial design field today. However, there are too many types of plastics, and if you dig into the contents, it is difficult to approach from the design field because it requires knowledge of petrochemistry or chemical engineering. However, as environmental problems caused by plastics have recently emerged, the need for understanding plastics in the industrial design field has increased. Methods Due to the lack of related prior research in the design field, I first looked at the characteristics and uses of plastics through literature research while referring to data in other fields related to plastics first, and then analyzed the problems caused by plastics. Then the solutions being tried to solve the problems were considered. Result Based on an understanding of existing petroleum-based plastics and bio-plastics, and also a detailed review of the negative effects plastics are currently having on people and the environment, 5 categories and 8 action items were derived to minimize such negative aspects when using plastic materials in the design field. Conclusion This study was attempted to examine the specific characteristics of plastic materials from the perspective of industrial design, what aspects are problematic, and how the design field should deal with that problem. It is hoped that this study will be helpful in starting the related discussion in the future in the field of design. 연구배경 플라스틱은 오늘날 산업디자인 분야에서 가장 널리 활용되는 소재 중 하나임에도 불구하고, 종류가 너무 많기도 하고 내용을 파고들어가다 보면 석유화학이나 화학공학적 지식을 필요로 하기 때문에 비전공자들이 접근하기가 쉽지 않다보니 아직까지 디자인분야에서 플라스틱과 관련된 선행 연구는 부족한 실정이다. 하지만 최근 들어 플라스틱으로 인해 발생하는 환경 문제가 세계적인 이슈로 대두되면서 산업디자인 분야에서의 플라스틱에 대한 이해의 필요성은 크게 증가하였다. 연구방법 지속가능한 디자인의 관점에서 플라스틱 소재를 조망할 수 있는 디자인 분야의 선행 연구가 부족하다보니 플라스틱과 관련된 타 분야 자료들을 주로 참고하면서 문헌 연구를 통해 플라스틱의 종류별 특성과 용도를 먼저 살펴보았고, 다음으로 플라스틱이 유발하는 문제들을 분석하였으며, 그 문제들을 해결하기 위해 시도되고 있는 현재의 해결책들까지 고찰하였다. 연구결과 기존에 사용되고 있는 석유계 플라스틱 및 바이오 플라스틱에 대한 이해와 플라스틱이 현재 사람과 환경에 끼치고 있는 부정적인 영향에 대한 상세한 고찰을 바탕으로 디자인 분야에서 플라스틱 소재 활용 시 그러한 부정적인 측면을 최소화하기 위해 참고할 수 있는 5개의 카테고리와 8가지 세부 실행 항목으로 이루어진 플라스틱 활용 가이드라인을 도출하였다. 결론 본 연구는 산업디자인의 관점에서 플라스틱 소재의 특징이 구체적으로 무엇이고 어떤 측면에서 문제가 되고 있으며 그 문제를 산업디자인 분야가 어떻게 다루어야 하는지를 고찰하기 위해 시도되었다. 본 연구가 디자인 분야에서 추후 관련된 논의를 본격적으로 시작하는데 도움이 되기를 기대한다.

Plastic recycling in South Korea: problems, challenges, and policy recommendations in the endemic era

송우람,박훈(Hun Park) 한국생태학회 2024 Journal of Ecology and Environment Vol.48 No.1

Background: Despite many environmental problems, plastic waste emissions have been a significant surge during last few decades in the Republic of Korea. Furthermore, the emergence of the coronavirus disease 2019 (COVID-19) pandemic has lead to an increased use and disposal of plastic waste worldwide. This paper tried to present summarized data related to the production and disposal of plastics especially before and after the COVID-19 pandemic with environmental impacts of plastics. Also, review of plastic waste reduction policies and feasible policies to promote an act for a safe, sustainable environment are presented. Results: Plastics cause many environmental problems due to their non-degrading properties and have a huge direct and indirect impact on Ecosystems and Public Health. Microplastics need a lot of attention because their environmental effects are not yet fully identified. Despite plastic’s significant impact on climate change, the impact is not yet widely known to the public. Since the COVID-19 pandemic, the use of plastic has surged and recycling has decreased due to the increase in delivery food and online shopping. Korea is introducing very active plastic and waste management policies, but it is necessary to implement more active policies by referring to the cases of other countries. Conclusions: In this article, we have scrutinized the evolution of plastic waste generation in the aftermath of the COVID-19 pandemic and delved into policy frameworks adopted by other nations, which South Korea can draw valuable lessons from. The formidable challenges posed by plastic waste, the remarkable shifts witnessed during the COVID-19 era, and the multifaceted response strategies elucidated in this paper all play a pivotal role in steering South Korea toward a sustainable future.