Study of structural changes and mesomorphic transitions of oriented poly(ethylene therephthalate) fibers in supercritical CO2

Plastic pollution is one of the crucial global challenges nowadays, and biodegradation is a promising approach to manage plastic waste in an environment-friendly and cost-effective way. In this study we identified the strain of fungus Trichoderma viride GZ1, which was characterized by particularly high pectinolytic activity. Using differential scanning calorimetry, Fourier-transform infrared spectroscopy techniques, and viscosity measurements we showed that three-month incubation of polylactide and polyethylene terephthalate in the presence of the fungus lead to significant changes of the surface of polylactide. Further, to gain insight into molecular mechanisms underneath the biodegradation process, western blot hybridization was used to show that in the presence of poly(ethylene terephthalate) (PET) in laboratory conditions the fungus produced hydrophobin proteins. The mycelium adhered to the plastic surface, which was confirmed by scanning electron microscopy, possibly due to the presence of hydrophobins. Further, using atomic force microscopy we demonstrated for the first time the formation of hydrophobin film on the surface of aliphatic polylactide (PLA) and PET by T. viride GZ1. This is the first stage of research that will be continued under environmental conditions, potentially leading to a practical application.

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Quantitative Analysis of Micro-structural Changes in a Bituminous Coal After Exposure to Supercritical CO2 and Water

Natural Resources Research ◽

10.1007/s11053-019-09463-y ◽

2019 ◽

Vol 28 (4) ◽

pp. 1639-1660 ◽

Cited By ~ 6

Author(s):

Guanglei Zhang ◽

P. G. Ranjith ◽

M. S. A. Perera ◽

Yiyu Lu ◽

Xavier Choi

Keyword(s):

Quantitative Analysis ◽

Supercritical Co2 ◽

Bituminous Coal ◽

Structural Changes

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Batch production of micron size particles from poly(ethylene glycol) using supercritical CO2 as a processing solvent

Chemical Engineering Science ◽

10.1016/j.ces.2006.04.034 ◽

2007 ◽

Vol 62 (6) ◽

pp. 1712-1720 ◽

Cited By ~ 30

Author(s):

Sameer P. Nalawade ◽

Francesco Picchioni ◽

L.P.B.M. Janssen

Keyword(s):

Ethylene Glycol ◽

Supercritical Co2 ◽

Poly Ethylene Glycol ◽

Batch Production ◽

Micron Size ◽

Poly Ethylene

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Study on effect of supercritical CO2 on structural ordering and charge transporting property in thiophene-based block copolymer

Japanese Journal of Applied Physics ◽

10.35848/1347-4065/ac47a9 ◽

2022 ◽

Author(s):

Satomi Hosokawa ◽

Eri Tomita ◽

Shinji Kanehashi ◽

Kenji Ogino

Keyword(s):

Supercritical Co2 ◽

Hole Mobility ◽

Amorphous Region ◽

Crystalline Region ◽

Space Charge Limited Current ◽

Conjugation Length ◽

Enhanced Mobility ◽

Poly Ethylene Oxide ◽

Poly Ethylene ◽

Effective Conjugation Length

Abstract We reported that supercritical (sc) annealing of poly(3-hexylthiophene) (P3HT), and its block copolymers with poly(ethylene oxide) (PEO) and polystyrene (PSt) brought about improvements in the crystal structure and hole mobility, determined by the space charge limited current (SCLC) measurement. P3HT-b-PEO showed the largest increase in mobility. From XRD profile, it was found that the treatment with scCO2 increased the crystallite size and crystallinity. UV-vis spectra showed that the effective conjugation length in the scCO2 treated films was increased compared to the as-spun, suggesting that CO2 molecules are incorporated into domains of the second block domains and P3HT amorphous region, and assist to alter the characteristics of the crystalline region. Then, it was considered that the change in the crystalline structure and the improvement of P3HT chains packing led to the enhanced mobility. Since PEO is known to have a higher affinity for CO2, the increase of mobility was specifically intensive.

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