• Elastomers and Composites
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• 제37권2호
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• pp.124-133
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• 2002

온화한 조건($80{\sim}110^{\circ}C$, 대기압)하에서 비누화반응에 의해 폐 PBT의 입자를 해중합하여다. PBT의 해중합은 KOH 보다 NaOH가 보다 효과적이었으며, 반응온도가 증가하고 입자의 크기가 작을수록 해중합은 증가하였다. 해중합속도는 표면반응이 율속단계로서 PBT 입자표면에 생성물이 형성되지 않은 미반응핵 모델에 의해 표현할수 있었다. 겉보기활성화에너지는 98.1KJ/mol 이었으며, 85.1, $105{\mu}m$인 PBT 입자를 6시간 동안 해중합하였을때 TPA의 회수율은 약 95%정도였다.

• 한국환경과학회지
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• 제24권8호
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• pp.1037-1043
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• 2015

Since single-use disposable plastic usage has steadily been increasing, recent trends in polymeric research point to increasing demand for eco-friend materials which reduce plastic waste. A huge amount of non-degradable polypropylene (PP)-based pots for seedling culture are discarded for transplantation. The purpose of this study is to investigate an eco-friendly biodegradable material as a possible substitute for PP pot. The blend of poly(lactic acid) (PLA) with poly(butylene adipate-co-terephthalate) (PBAT) was used because of its good mechanical and flexible properties as well as biodegradation. After landfill, various properties of the blend pot were investigated by UTM, SEM, NMR and TGA. The results showed the tensile strength of the blend film rapidly decreased after 5 weeks of landfill due to degradation. From NMR data after landfill, the composition of PLA in the blend was decreased. These results indicate that the biodegradation of the blend preferentially occurs in PLA component. To investigate the effect of holes in pot bottom and side on root growth, a plant in the pot was grown. Some roots came out through holes as landfill period increases. These results indicate that the eco-friendly pot can be directly planted without the removal of pot.

• 한국환경과학회지
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• 제24권1호
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• pp.9-15
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• 2015

Sustainable and eco-friendly polymers, natural polymers, bio-based polymers, and degradable polyesters, are of growing interest because of environmental concerns associated with waste plastics and emissions of carbon dioxide from preparation of petroleum-based polymers. Degradable polymers, poly(butylene adipate-co-terephthalate) (PBAT), poly(propylene carbonate) (PPC), and poly(L-lactic acid) (PLLA), are related to reduction of carbon dioxide in processing. To improve a weak mechanical property of a degradable polymer, a blending method is widely used. This study was forced on the component separation of degradable polymer blends for effective recycling. The melt-mixed blend films in a specific solvent were separated by two layers. Each layer was analysed by FT-IR, DSC, and contact angle measurements. The results showed that each component in the PPC/PLLA and PPC/PBAT blends was successfully separated by a solvent.

• Elastomers and Composites
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• 제55권4호
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• pp.347-353
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• 2020

Stearic acid (SA), polyethylene glycol (PEG), and malic acid (MA) have been used to modify the surface of waste gypsum to develop corresponding poly (butylene adipate-co-terephthalate) (PBAT) composites. According to the mechanical properties, MA-treated gypsum (MA-gypsum) showed the best performance, whereas SA-gypsum showed the worst performance. In contrast to SA and PEG (having -COOH and -OH as polar functional groups, respectively), the presence of both -OH and -COOH in MA is responsible for the superior surface treatment of gypsum and its better dispersion in the polymer matrix (as revealed by FE-SEM analyses). The presence of long aliphatic chain in SA is supposed to inhibit the dispersion of SA-gypsum. Further, the performance of MA-gypsum/PBAT was enhanced by adding polylactic acid (PLA). The maximum optimized contents of MA-gypsum and PLA are 20 and 7.5 wt% for developing a high-performance PBAT composite.