The Experts below are selected from a list of 291 Experts worldwide ranked by ideXlab platform

Robert M Enick - One of the best experts on this subject based on the ideXlab platform.

  • Anthraquinone Siloxanes as Thickening Agents for Supercritical CO2
    Energy & Fuels, 2016
    Co-Authors: Michael Joseph O'brien, Robert James Perry, Mark D. Doherty, Aman Dhuwe, Eric J Beckman, Robert M Enick
    Abstract:

    A series of aromatic amide-functionalized, low-molecular-weight Polydimethylsiloxanes were synthesized, and their solubility and thickening ability in supercritical carbon dioxide (scCO2) were evaluated. Amide-terminated polydimethylsiloxane (PDMS) oligomers with simple or electron-rich aromatic groups were found to be moderate viscosity oils, indicating that the end groups do not interact strongly enough to be thickeners. Attachment of electron-deficient aromatic groups, such as 4-nitrophenyl, biphenyl, or anthraquinone, onto these amides produced solid polysiloxanes, even at relatively higher degrees of polymerization on the PDMS core (x = 40–50). PDMS derivatives with anthraquinone-2-carboxamide (AQCA) end groups were clear, somewhat rubbery solids. These compounds were found to act as thickeners and gelators of hexanes. In addition, they were able to thicken and/or gel mixtures of hexane and scCO2. The best results were obtained with an AQCA-terminated branched PDMS. Branched fluorenone-2-carboxamide ...

  • Anthraquinone Siloxanes as Thickening Agents for Supercritical CO2
    2016
    Co-Authors: Michael J. O’brien, Robert James Perry, Mark D. Doherty, Aman Dhuwe, Eric J Beckman, Jason J. Lee, Robert M Enick
    Abstract:

    A series of aromatic amide-functionalized, low-molecular-weight Polydimethylsiloxanes were synthesized, and their solubility and thickening ability in supercritical carbon dioxide (scCO2) were evaluated. Amide-terminated polydimethylsiloxane (PDMS) oligomers with simple or electron-rich aromatic groups were found to be moderate viscosity oils, indicating that the end groups do not interact strongly enough to be thickeners. Attachment of electron-deficient aromatic groups, such as 4-nitrophenyl, biphenyl, or anthraquinone, onto these amides produced solid polysiloxanes, even at relatively higher degrees of polymerization on the PDMS core (x = 40–50). PDMS derivatives with anthraquinone-2-carboxamide (AQCA) end groups were clear, somewhat rubbery solids. These compounds were found to act as thickeners and gelators of hexanes. In addition, they were able to thicken and/or gel mixtures of hexane and scCO2. The best results were obtained with an AQCA-terminated branched PDMS. Branched fluorenone-2-carboxamide was found to be a waxy solid that was very soluble and, therefore, not a thickener for hexane, and fluorenone-4-carboxamide was a viscous oil, indicating that these amide groups did not interact sufficiently to be useful. 10,10-Dioxothioxanthone-2-carboxamides were more efficient gelators of hexane than anthraquinone-2-carboxamides. However, they were not sufficiently soluble in scCO2, even in the presence of hexane co-solvent, to be useful as thickeners

Alain Tchapla - One of the best experts on this subject based on the ideXlab platform.

Hua Bai - One of the best experts on this subject based on the ideXlab platform.

  • 3D Printing of a Polydimethylsiloxane/Polytetrafluoroethylene Composite Elastomer and its Application in a Triboelectric Nanogenerator
    ACS applied materials & interfaces, 2020
    Co-Authors: Renhao Zheng, Yuxin Chen, Hang Chi, Hong Qiu, Hao Xue, Hua Bai
    Abstract:

    Silicone rubber elastomers are broadly used in various fields, where the three-dimensional (3D) printing of silicone rubber elastomers is important for the free construction of complex structures. Herein, a series of polydimethylsiloxane/polytetrafluoroethylene composite inks for direct-ink-writing 3D printing are developed. The inks are prepared by directly mixing a silicone rubber liquid precursor with polytetrafluoroethylene micropowder. The polytetrafluoroethylene micropowder serves as a thixotropic agent to regulate the rheological properties of the polydimethylsiloxane precursor to fulfill the requirement of 3D printing and endow the composite material with high electron affinity. The printed polydimethylsiloxane/polytetrafluoroethylene composite elastomer exhibits excellent elasticity and cyclic stability. A high-performance triboelectric nanogenerator is constructed with the 3D-printed polydimethylsiloxane/polytetrafluoroethylene composite as the triboelectric layer and elastic structure. This work establishes a new method of 3D printing polydimethylsiloxane-based elastomers and thus provides a new technique for constructing complex structures in flexible devices.

Michael Joseph O'brien - One of the best experts on this subject based on the ideXlab platform.

  • Anthraquinone Siloxanes as Thickening Agents for Supercritical CO2
    Energy & Fuels, 2016
    Co-Authors: Michael Joseph O'brien, Robert James Perry, Mark D. Doherty, Aman Dhuwe, Eric J Beckman, Robert M Enick
    Abstract:

    A series of aromatic amide-functionalized, low-molecular-weight Polydimethylsiloxanes were synthesized, and their solubility and thickening ability in supercritical carbon dioxide (scCO2) were evaluated. Amide-terminated polydimethylsiloxane (PDMS) oligomers with simple or electron-rich aromatic groups were found to be moderate viscosity oils, indicating that the end groups do not interact strongly enough to be thickeners. Attachment of electron-deficient aromatic groups, such as 4-nitrophenyl, biphenyl, or anthraquinone, onto these amides produced solid polysiloxanes, even at relatively higher degrees of polymerization on the PDMS core (x = 40–50). PDMS derivatives with anthraquinone-2-carboxamide (AQCA) end groups were clear, somewhat rubbery solids. These compounds were found to act as thickeners and gelators of hexanes. In addition, they were able to thicken and/or gel mixtures of hexane and scCO2. The best results were obtained with an AQCA-terminated branched PDMS. Branched fluorenone-2-carboxamide ...

Sandrine Hamm - One of the best experts on this subject based on the ideXlab platform.