The stability, liquid ranges, and thermal decomposition of a series of quatemized and protonated ... more The stability, liquid ranges, and thermal decomposition of a series of quatemized and protonated imidazolium nitrate and picrate salts have been investigated. The quatemized, Y Y-dialky lated imidazolium salts are * more stable than the protonated examples, and salts with picrate anions are surprisingly more stable than the corresponding nitrate salts and in each case, decompose exothermically yielding volatile decomposition products.
J. Mater. Chem., 2005, 15, 5174-5180 DOI:10.1039/B508927A (Paper). Ionic liquids as solvent and s... more J. Mater. Chem., 2005, 15, 5174-5180 DOI:10.1039/B508927A (Paper). Ionic liquids as solvent and solvent additives for the synthesis of solgel materials. Marc A. Klingshirnb, Scott K. Speara, John D. Holbreyc and Robin D. Rogers ...
ABSTRACT There is an increasing willingness to develop new cellulose-based materials, particularl... more ABSTRACT There is an increasing willingness to develop new cellulose-based materials, particularly from homogeneous solution, due to the fact that cellulose is the earth's most abundant biorenewable resource. The opportunity to use ionic liquids as solvents for clean extraction and processing of cellulose has been investigated. Cellulose can be dissolved in a number of ionic liquids and easily regenerated by contacting with water. This allows a simple, benign system for the processing of cellulose into fibers, monoliths, and films by forming into an aqueous phase. This has potential environmental and cost advantages over current processing methodologies which make use of volatile or hazardous solvents.
Industrial Engineering Chemistry Research, Feb 1, 2010
In common with many poly(ethylene glycol)s (PEGs), a poly(ethylene oxide)-poly(propylene oxide) r... more In common with many poly(ethylene glycol)s (PEGs), a poly(ethylene oxide)-poly(propylene oxide) random copolymer (EO-PO, with EO/PO) 1:1.3) of molecular weight 3320 g • mol-1 , known as Sunbright-3320 (SB-3320), can be salted out of aqueous solution using kosmotropic salts such as (NH 4) 2 SO 4 to form aqueous biphasic systems (ABSs) comprising upper polymer-rich and lower salt-rich aqueous phases. The effects of temperature on these liquid/liquid ABSs and related solid/liquid resin-based systems, where one end of the polymer has been covalently attached to a solid support, have been studied. Distribution ratios of NH 4 99 TcO 4 were determined radiometrically at various polymer and salt concentrations and temperatures. SB-3320grafted poly(styrene) resins exhibit opposite effects of variable-temperature partitioning compared to the SB-3320-based ABS. However, the results are complicated because of the conformational changes that are possible for the SB-3320 polymer. Enthalpy and entropy changes were found to be temperature-dependent. The differences observed between the distribution of 99 TcO 4 in EO-PO-based systems versus PEG-based systems can be attributed to the lower cloud point temperatures and probable conformational changes for the EO-PO systems.
The nuclear legacy. The development of nuclear energy in the United States over the past 60 years... more The nuclear legacy. The development of nuclear energy in the United States over the past 60 years has left nuclear facilities with stockpiles of high-and low-level nuclear waste approaching tens of millions of gallons. At many legacy sites, primarily those involved in ...
Twenty-eight novel salts with tetramethyl-, tetraethyl-, and tetrabutylammonium and 1-butyl-3-met... more Twenty-eight novel salts with tetramethyl-, tetraethyl-, and tetrabutylammonium and 1-butyl-3-methylimidazolium cations paired with 3,5-dinitro-1,2,4-triazolate, 4-nitro-1,2,3-triazolate, 2,4-dinitroimidazolate, 4,5-dinitroimidazolate, 4,5-dicyanoimidazolate, 4-nitroimidazolate, and tetrazolate anions have been prepared and characterized by using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and single-crystal X-ray crystallography. The effects of cation and anion type and structure on the physicochemical properties of the resulting salts, including several ionic liquids, have been examined and discussed. Ionic liquids (defined as having m.p.<100 degrees C) were obtained with all combinations of the 1-butyl-3-methylimidazolium cation ([C(4)mim](+)) and the heterocyclic azolate anions studied, and with several combinations of tetraethyl or tetrabutylammonium cations and the azolate anions. The [C(4)mim](+) azolates were liquid at room temperature exhibiting large liquid ranges and forming glasses on cooling with glass-transition temperatures in the range of -53 to -82 degrees C (except for the 3,5-dinitro-1,2,4-triazolate salt with m.p. 33 degrees C). Six crystal structures of the corresponding tetraalkylammonium salts were determined and the effects of changes to the cations and anions on the packing of the structure have been investigated.
Page 1. Chapter 5 Applying Ionic Liquids for Controlled Processing of Polymer Materials John D. H... more Page 1. Chapter 5 Applying Ionic Liquids for Controlled Processing of Polymer Materials John D. Holbrey, Ji Chen, Megan B. Turner, Richard P. Swatloski, Scott K. Spear, and Robin D. Rogers Center for Green Manufacturing ...
... on Protein Stability in Ionic Liquid Solutions Megan B. Turner1,2, John D. Holbrey1, Scott K.... more ... on Protein Stability in Ionic Liquid Solutions Megan B. Turner1,2, John D. Holbrey1, Scott K. Spear1, Marc L. Pusey3, and Robin D. Rogers1,2 ... M.; Ding, Z.; Moulton, R.; Bard, AJLangmuir 2002, 18, 1734-1742. (e) Wilkes, JS; Levisky, J. Α.; Wilson, R. Α.; Hussey, CL Inorg. Chem. ...
The stability, liquid ranges, and thermal decomposition of a series of quatemized and protonated ... more The stability, liquid ranges, and thermal decomposition of a series of quatemized and protonated imidazolium nitrate and picrate salts have been investigated. The quatemized, Y Y-dialky lated imidazolium salts are * more stable than the protonated examples, and salts with picrate anions are surprisingly more stable than the corresponding nitrate salts and in each case, decompose exothermically yielding volatile decomposition products.
J. Mater. Chem., 2005, 15, 5174-5180 DOI:10.1039/B508927A (Paper). Ionic liquids as solvent and s... more J. Mater. Chem., 2005, 15, 5174-5180 DOI:10.1039/B508927A (Paper). Ionic liquids as solvent and solvent additives for the synthesis of solgel materials. Marc A. Klingshirnb, Scott K. Speara, John D. Holbreyc and Robin D. Rogers ...
ABSTRACT There is an increasing willingness to develop new cellulose-based materials, particularl... more ABSTRACT There is an increasing willingness to develop new cellulose-based materials, particularly from homogeneous solution, due to the fact that cellulose is the earth's most abundant biorenewable resource. The opportunity to use ionic liquids as solvents for clean extraction and processing of cellulose has been investigated. Cellulose can be dissolved in a number of ionic liquids and easily regenerated by contacting with water. This allows a simple, benign system for the processing of cellulose into fibers, monoliths, and films by forming into an aqueous phase. This has potential environmental and cost advantages over current processing methodologies which make use of volatile or hazardous solvents.
Industrial Engineering Chemistry Research, Feb 1, 2010
In common with many poly(ethylene glycol)s (PEGs), a poly(ethylene oxide)-poly(propylene oxide) r... more In common with many poly(ethylene glycol)s (PEGs), a poly(ethylene oxide)-poly(propylene oxide) random copolymer (EO-PO, with EO/PO) 1:1.3) of molecular weight 3320 g • mol-1 , known as Sunbright-3320 (SB-3320), can be salted out of aqueous solution using kosmotropic salts such as (NH 4) 2 SO 4 to form aqueous biphasic systems (ABSs) comprising upper polymer-rich and lower salt-rich aqueous phases. The effects of temperature on these liquid/liquid ABSs and related solid/liquid resin-based systems, where one end of the polymer has been covalently attached to a solid support, have been studied. Distribution ratios of NH 4 99 TcO 4 were determined radiometrically at various polymer and salt concentrations and temperatures. SB-3320grafted poly(styrene) resins exhibit opposite effects of variable-temperature partitioning compared to the SB-3320-based ABS. However, the results are complicated because of the conformational changes that are possible for the SB-3320 polymer. Enthalpy and entropy changes were found to be temperature-dependent. The differences observed between the distribution of 99 TcO 4 in EO-PO-based systems versus PEG-based systems can be attributed to the lower cloud point temperatures and probable conformational changes for the EO-PO systems.
The nuclear legacy. The development of nuclear energy in the United States over the past 60 years... more The nuclear legacy. The development of nuclear energy in the United States over the past 60 years has left nuclear facilities with stockpiles of high-and low-level nuclear waste approaching tens of millions of gallons. At many legacy sites, primarily those involved in ...
Twenty-eight novel salts with tetramethyl-, tetraethyl-, and tetrabutylammonium and 1-butyl-3-met... more Twenty-eight novel salts with tetramethyl-, tetraethyl-, and tetrabutylammonium and 1-butyl-3-methylimidazolium cations paired with 3,5-dinitro-1,2,4-triazolate, 4-nitro-1,2,3-triazolate, 2,4-dinitroimidazolate, 4,5-dinitroimidazolate, 4,5-dicyanoimidazolate, 4-nitroimidazolate, and tetrazolate anions have been prepared and characterized by using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and single-crystal X-ray crystallography. The effects of cation and anion type and structure on the physicochemical properties of the resulting salts, including several ionic liquids, have been examined and discussed. Ionic liquids (defined as having m.p.<100 degrees C) were obtained with all combinations of the 1-butyl-3-methylimidazolium cation ([C(4)mim](+)) and the heterocyclic azolate anions studied, and with several combinations of tetraethyl or tetrabutylammonium cations and the azolate anions. The [C(4)mim](+) azolates were liquid at room temperature exhibiting large liquid ranges and forming glasses on cooling with glass-transition temperatures in the range of -53 to -82 degrees C (except for the 3,5-dinitro-1,2,4-triazolate salt with m.p. 33 degrees C). Six crystal structures of the corresponding tetraalkylammonium salts were determined and the effects of changes to the cations and anions on the packing of the structure have been investigated.
Page 1. Chapter 5 Applying Ionic Liquids for Controlled Processing of Polymer Materials John D. H... more Page 1. Chapter 5 Applying Ionic Liquids for Controlled Processing of Polymer Materials John D. Holbrey, Ji Chen, Megan B. Turner, Richard P. Swatloski, Scott K. Spear, and Robin D. Rogers Center for Green Manufacturing ...
... on Protein Stability in Ionic Liquid Solutions Megan B. Turner1,2, John D. Holbrey1, Scott K.... more ... on Protein Stability in Ionic Liquid Solutions Megan B. Turner1,2, John D. Holbrey1, Scott K. Spear1, Marc L. Pusey3, and Robin D. Rogers1,2 ... M.; Ding, Z.; Moulton, R.; Bard, AJLangmuir 2002, 18, 1734-1742. (e) Wilkes, JS; Levisky, J. Α.; Wilson, R. Α.; Hussey, CL Inorg. Chem. ...
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