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Influence of Component Ratio on Thermal and Mechanical Properties of Terpenoid-Sulfur Composites. JOURNAL OF COMPOSITES SCIENCE 2021. [DOI: 10.3390/jcs5100257] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Terpenoids are potentially sustainable replacements for petrochemical olefins. Sulfur is a waste product produced in large quantities from fossil fuel refining. Several composites with attractive properties have recently been made from terpenoids and sulfur. This report details the extent to which the ratio of sulfur to terpenoid and the terpenoid olefin content influences the thermal and mechanical properties of such terpenoid-sulfur composites. The terpenoids selected were diunsaturated geraniol and triunsaturated farnesol that, upon their inverse vulcanization with elemental sulfur, yield composites GerSx and FarSx, respectively (x = wt % sulfur). The wt % sulfur in the monomer feed was varied from 30–95 for this study, providing twelve materials. Mechanical analysis of these materials was undertaken by compressive and tensile strength techniques. Differential scanning calorimetric analysis revealed both polymeric and orthorhombic sulfur present in the materials with glass transition temperatures (Tg) of −37 °C to −13 °C and melt temperatures (Tm) of 119 to 104 °C. The crystallinity of composites decreases as the weight fraction of sulfur decreases and composites having the highest olefin content exhibit no detectable crystalline microstructures. The compressive strength of the materials showed increasing strength for higher olefin-content materials for both GerSx (with compressive strength of up to 32 MPa) and FarSx (with compressive strength of up to 43 MPa). The improved strength with increasing olefin content levels off at around 80–85% of terpenoid, after which point both tensile and compressive strength diminish.
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Zarubin VA, Li TD, Humagain S, Ji H, Yager KG, Greenbaum SG, Vuong LT. Improved Anisotropic Thermoelectric Behavior of Poly(3,4-ethylenedioxythiophene):Poly(styrenesulfonate) via Magnetophoresis. ACS OMEGA 2018; 3:12554-12561. [PMID: 31457990 PMCID: PMC6644634 DOI: 10.1021/acsomega.8b00999] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Accepted: 09/20/2018] [Indexed: 06/10/2023]
Abstract
There is strong demand for achieving morphological control of conducting polymers in its many potential applications, from energy harvesting to spintronics. Here, the static magnetic-field-induced alignment of poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) particles is demonstrated. PEDOT:PSS thin films cast under modest mT-level magnetic fields exhibit a fourfold increase in the Seebeck coefficient and doubled electrical conductivity. Atomic force microscopy measurements confirm the presence of conducting islands that exhibit a 10-fold increase in the local charge carrier mobility and threshold behavior that is associated with phase separation. High-resolution scanning electron microscopy identifies a consistent structural coil-to-rod transition, and three-dimensional time-of-flight secondary-ion mass spectrometry imaging shows that the rodlike structures coincide with PEDOT domains that generally align with the magnetic field and cluster on the outer surface. Grazing-incidence small-angle X-ray scattering, Raman spectra, electron paramagnetic resonance, and circular dichroism spectroscopy point to the physical nature of the magnetophoretic alignment, which is expected to occur via magnetic coupling of PEDOT domains with polaron modes. Because casting under mT-level magnetic fields increases the electrical conductivity and Seebeck coefficient of PEDOT:PSS thin films without additional dopants that commonly limit the thermoelectric performance, our research reveals that low-field magnetophoresis significantly influences the structure and corresponding physical properties of PEDOT:PSS. Our results also point to concerns that the presence of small external magnetic fields in laboratory settings may appreciably and inadvertently influence the PEDOT:PSS morphology during settling, drying, or annealing processes.
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Affiliation(s)
- Vera A. Zarubin
- Bronx
High School of Science, 75 W 205th Street, Bronx, New York 10468, United
States
| | - Tai-De Li
- Department
of Physics, City College of New York and Advanced Science Research
Center, Graduate Center of the City University
of New York, 85 St Nicholas
Terrace, New York 10031, United States
| | - Sunita Humagain
- Department
of Physics, Hunter College of the
City University of New York, 695 Park Avenue, New York, New York 10065, United
States
- Department
of Physics, Graduate Center of the City
University of New York, 365 5th Avenue, New York, New York 10016, United
States
| | - Haojie Ji
- Department
of Physics, Queens College of the
City University of New York, 65-30 Kissena Blvd, Flushing, New York 11367, United
States
| | - Kevin G. Yager
- Center
for Functional Nanomaterials, Brookhaven
National Laboratory, Upton, New York 11973, United States
| | - Steven G. Greenbaum
- Department
of Physics, Hunter College of the
City University of New York, 695 Park Avenue, New York, New York 10065, United
States
- Department
of Physics, Graduate Center of the City
University of New York, 365 5th Avenue, New York, New York 10016, United
States
| | - Luat T. Vuong
- Department
of Physics, Queens College of the
City University of New York, 65-30 Kissena Blvd, Flushing, New York 11367, United
States
- Department
of Physics, Graduate Center of the City
University of New York, 365 5th Avenue, New York, New York 10016, United
States
- Department
of Mechanical Engineering, University of
California at Riverside, Bourns Hall, Riverside, California 92521, United States
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Yashima E, Ousaka N, Taura D, Shimomura K, Ikai T, Maeda K. Supramolecular Helical Systems: Helical Assemblies of Small Molecules, Foldamers, and Polymers with Chiral Amplification and Their Functions. Chem Rev 2016; 116:13752-13990. [PMID: 27754649 DOI: 10.1021/acs.chemrev.6b00354] [Citation(s) in RCA: 1198] [Impact Index Per Article: 149.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
In this review, we describe the recent advances in supramolecular helical assemblies formed from chiral and achiral small molecules, oligomers (foldamers), and helical and nonhelical polymers from the viewpoints of their formations with unique chiral phenomena, such as amplification of chirality during the dynamic helically assembled processes, properties, and specific functionalities, some of which have not been observed in or achieved by biological systems. In addition, a brief historical overview of the helical assemblies of small molecules and remarkable progress in the synthesis of single-stranded and multistranded helical foldamers and polymers, their properties, structures, and functions, mainly since 2009, will also be described.
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Affiliation(s)
- Eiji Yashima
- Department of Molecular Design and Engineering, Graduate School of Engineering, Nagoya University , Chikusa-ku, Nagoya 464-8603, Japan
| | - Naoki Ousaka
- Department of Molecular Design and Engineering, Graduate School of Engineering, Nagoya University , Chikusa-ku, Nagoya 464-8603, Japan
| | - Daisuke Taura
- Department of Molecular Design and Engineering, Graduate School of Engineering, Nagoya University , Chikusa-ku, Nagoya 464-8603, Japan
| | - Kouhei Shimomura
- Department of Molecular Design and Engineering, Graduate School of Engineering, Nagoya University , Chikusa-ku, Nagoya 464-8603, Japan
| | - Tomoyuki Ikai
- Graduate School of Natural Science and Technology, Kanazawa University , Kakuma-machi, Kanazawa 920-1192, Japan
| | - Katsuhiro Maeda
- Graduate School of Natural Science and Technology, Kanazawa University , Kakuma-machi, Kanazawa 920-1192, Japan
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