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Valdez CA, Rosales JA, Vu AK, Leif RN. Detection and confirmation of fentanyls in high clay-content soil by electron ionization gas chromatography-mass spectrometry. J Forensic Sci 2023; 68:2138-2152. [PMID: 37568257 DOI: 10.1111/1556-4029.15354] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Revised: 07/26/2023] [Accepted: 07/27/2023] [Indexed: 08/13/2023]
Abstract
Detection of illicit drugs in the environment, particularly in soils, often suggests the present or past location of a clandestine production center for these substances. Thus, development of efficient methods for the analysis and detection of these chemicals is of paramount importance in the field of chemical forensics. In this work, a method involving the extraction and retrospective confirmation of fentanyl, acetylfentanyl, thiofentanyl, and acetylthiofentanyl using trichloroethoxycarbonylation chemistry in a high clay-content soil is presented. The soil was spiked separately with each fentanyl at two concentrations (1 and 10 μg/g) and their extraction accomplished using ethyl acetate and aqueous NH4 OH (pH ~ 11.4) with extraction recoveries ranging from ~56% to 82% for the high-concentration (10 μg/g) samples while ranging from ~68% to 83% for the low-concentration (1 μg/g) samples. After their extraction, residues containing each fentanyl were reacted with 2,2,2-trichloroethoxycarbonyl chloride (Troc-Cl) to generate two unique and predictable products from each opioid that can be used to retrospectively confirm their presence and identity using EI-GC-MS. The method's limit of detection (MDL/LOD) for Troc-norfentanyl and Troc-noracetylfentanyl were estimated to be 29.4 and 31.8 ng/mL in the organic extracts. In addition, the method's limit of quantitation for Troc-norfentanyl and Troc-noracetylfentanyl were determined to be 88.2 and 95.5 ng/mL, respectively. Collectively, the results presented herein strengthen the use of chloroformate chemistry as an additional chemical tool to confirm the presence of these highly toxic and lethal substances in the environment.
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Affiliation(s)
- Carlos A Valdez
- Global Security Directorate, Lawrence Livemore National Laboratory, Livermore, California, USA
- Physical and Life Sciences Directorate, Lawrence Livemore National Laboratory, Livermore, California, USA
- Nuclear and Chemical Sciences Division, Lawrence Livemore National Laboratory, Livermore, California, USA
- Forensic Science Center, Lawrence Livemore National Laboratory, Livermore, California, USA
| | - José A Rosales
- Global Security Directorate, Lawrence Livemore National Laboratory, Livermore, California, USA
- Nuclear and Chemical Sciences Division, Lawrence Livemore National Laboratory, Livermore, California, USA
- Forensic Science Center, Lawrence Livemore National Laboratory, Livermore, California, USA
- NNSA-MSIIP Summer Fellow, University of Texas, El Paso, Texas, USA
| | - Alexander K Vu
- Global Security Directorate, Lawrence Livemore National Laboratory, Livermore, California, USA
- Physical and Life Sciences Directorate, Lawrence Livemore National Laboratory, Livermore, California, USA
- Nuclear and Chemical Sciences Division, Lawrence Livemore National Laboratory, Livermore, California, USA
- Forensic Science Center, Lawrence Livemore National Laboratory, Livermore, California, USA
| | - Roald N Leif
- Global Security Directorate, Lawrence Livemore National Laboratory, Livermore, California, USA
- Physical and Life Sciences Directorate, Lawrence Livemore National Laboratory, Livermore, California, USA
- Nuclear and Chemical Sciences Division, Lawrence Livemore National Laboratory, Livermore, California, USA
- Forensic Science Center, Lawrence Livemore National Laboratory, Livermore, California, USA
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2
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Valdez CA, Vu AK, Hok S, Alcaraz A. Practical benzylation of N,N-substituted ethanolamines related to chemical warfare agents for analysis and detection by electron ionization gas chromatography-mass spectrometry. J Forensic Sci 2023; 68:1923-1931. [PMID: 37578282 DOI: 10.1111/1556-4029.15357] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Revised: 07/31/2023] [Accepted: 08/01/2023] [Indexed: 08/15/2023]
Abstract
The benzylation of three low molecular weight N,N-disubstituted ethanolamines related to chemical warfare agents (CWAs) to furnish derivatives with improved gas chromatography-mass spectrometry (GC-MS) profiles is described. Due to their low molecular weight and polar nature, N,N-disubstituted ethanolamines are notoriously difficult to detect by routine GC-MS analyses during Organisation for the Prohibition of Chemical Weapons (OPCW) proficiency tests (PTs), particularly in scenarios when they are present at low levels (~1-10 ppm) amidst more abundant interferences. Our studies revealed that the optimal derivatization conditions involved the treatment of the ethanolamine with benzyl bromide in the presence of an inorganic base (e.g., Na2 CO3 ) in dichloromethane at 55°C for 2 h. This optimized set of conditions was then successfully applied to the derivatization of N,N-dimethylethanolamine, N,N-diethylethanolamine and N,N-diisopropylethanolamine present separately at 1 and 10 μg/mL concentrations in a glycerol-rich matrix sample featured in the 48th OPCW PT. The benzylated derivatives of the three ethanolamines possessed retention times long enough to clear the massive glycerol-containing matrix interferences. The protocol herein is introduced as an alternative method for derivatization of these CWA and pharmaceutically important species and should find broad applicability in laboratories where routine forensic analysis is carried out.
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Affiliation(s)
- Carlos A Valdez
- Nuclear and Chemical Sciences Division, Lawrence Livermore National Laboratory, Livermore, California, USA
- Global Security Directorate, Lawrence Livermore National Laboratory, Livermore, California, USA
- Forensic Science Center, Lawrence Livermore National Laboratory, Livermore, California, USA
| | - Alexander K Vu
- Nuclear and Chemical Sciences Division, Lawrence Livermore National Laboratory, Livermore, California, USA
- Global Security Directorate, Lawrence Livermore National Laboratory, Livermore, California, USA
- Forensic Science Center, Lawrence Livermore National Laboratory, Livermore, California, USA
| | - Saphon Hok
- Nuclear and Chemical Sciences Division, Lawrence Livermore National Laboratory, Livermore, California, USA
- Global Security Directorate, Lawrence Livermore National Laboratory, Livermore, California, USA
- Forensic Science Center, Lawrence Livermore National Laboratory, Livermore, California, USA
| | - Armando Alcaraz
- Nuclear and Chemical Sciences Division, Lawrence Livermore National Laboratory, Livermore, California, USA
- Global Security Directorate, Lawrence Livermore National Laboratory, Livermore, California, USA
- Forensic Science Center, Lawrence Livermore National Laboratory, Livermore, California, USA
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3
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Polynorbornenes bearing ether fragments in substituents: Promising membrane materials with enhanced CO2 permeability. J Memb Sci 2022. [DOI: 10.1016/j.memsci.2022.120340] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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Nicolas C, Huang J, Richaud E, David A, Gac PYL, Minne W, Drozdzak R, Recher G, Fontaine L, Montembault V. Enhanced thermo-oxidative stability of polydicyclopentadiene containing covalently bound nitroxide groups. Polym Degrad Stab 2022. [DOI: 10.1016/j.polymdegradstab.2021.109765] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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5
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Wang X, Jeong YL, Love C, Stretz HA, Stein GE, Long BK. Design, synthesis, and characterization of vinyl-addition polynorbornenes with tunable thermal properties. Polym Chem 2021. [DOI: 10.1039/d1py01050f] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Substituents were introduced onto addition polynorbornenes to modify their thermal properties. The resultant materials displayed depressed glass-transition temperatures, high decomposition temperatures, and could be melt-processed.
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Affiliation(s)
- Xinyi Wang
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee, 37996-1660, USA
| | - Yewon L. Jeong
- Department of Chemical & Biomolecular Engineering, University of Tennessee, Knoxville, Tennessee, 37996-1660, USA
| | - Christopher Love
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee, 37996-1660, USA
| | - Holly A. Stretz
- Department of Chemical Engineering, Tennessee Tech University, Cookeville, Tennessee, 38505, USA
| | - Gila E. Stein
- Department of Chemical & Biomolecular Engineering, University of Tennessee, Knoxville, Tennessee, 37996-1660, USA
| | - Brian K. Long
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee, 37996-1660, USA
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Chriti D, Raptopoulos G, Brandenburg B, Paraskevopoulou P. Large, Rapid Swelling of High- cis Polydicyclopentadiene Aerogels Suitable for Solvent-Responsive Actuators. Polymers (Basel) 2020; 12:polym12051033. [PMID: 32370122 PMCID: PMC7284835 DOI: 10.3390/polym12051033] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2020] [Revised: 04/24/2020] [Accepted: 04/28/2020] [Indexed: 11/16/2022] Open
Abstract
High-cis polydicyclopentadiene (PDCPD) aerogels were synthesized using ring opening metathesis polymerization (ROMP) of dicyclopentadiene (DCPD) with a relatively air-stable ditungsten catalytic system, Na[W2(-Cl)3Cl4(THF)2]·(THF)3 (W2; (W 3 W)6+, a΄2e΄4), and norbornadiene (NBD)as a co-initiator. These aerogels are compared in terms of chemical structure and material properties with literature PDCPD aerogels obtained using well-established Ru-based alkylidenes as catalysts. The use of NBD as a co-initiator enhances the degree of crosslinking versus the more frequently used phenylacetylene (PA), yielding materials with a controlled molecular structure that would persist solvent swelling. Indeed, those PDCPD aerogels absorb selected organic solvents (e.g., chloroform, tetrahydrofuran) and swell rapidly, in some cases up to 4 times their original volume within 10 min, thus showing their potential for applications in chemical sensors and solvent-responsive actuators. The advantage of aerogels versus xerogels or dense polymers for these applications is their open porosity, which provides rapid access of the solvent to their interior, thus decreasing the diffusion distance inside the polymer itself, which in turn accelerates the response to the solvents of interest.
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Affiliation(s)
- Despoina Chriti
- Laboratory of Inorganic Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis Zografou, 15771 Athens, Greece; (D.C.); (G.R.)
| | - Grigorios Raptopoulos
- Laboratory of Inorganic Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis Zografou, 15771 Athens, Greece; (D.C.); (G.R.)
| | | | - Patrina Paraskevopoulou
- Laboratory of Inorganic Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis Zografou, 15771 Athens, Greece; (D.C.); (G.R.)
- Correspondence: ; Tel.: +30-210-727-4381; Fax: +30-210-727-4782
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Synthetic Polymer Aerogels in Particulate Form. MATERIALS 2019; 12:ma12091543. [PMID: 31083421 PMCID: PMC6539448 DOI: 10.3390/ma12091543] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/28/2019] [Revised: 04/22/2019] [Accepted: 05/06/2019] [Indexed: 11/17/2022]
Abstract
Aerogels have been defined as solid colloidal or polymeric networks of nanoparticles that are expanded throughout their entire volume by a gas. They have high surface areas, low thermal conductivities, low dielectric constants, and high acoustic attenuation, all of which are very attractive properties for applications that range from thermal and acoustic insulation to dielectrics to drug delivery. However, one of the most important impediments to that potential has been that most efforts have been concentrated on monolithic aerogels, which are prone to defects and their production requires long and costly processing. An alternative approach is to consider manufacturing aerogels in particulate form. Recognizing that need, the European Commission funded “NanoHybrids”, a 3.5 years project under the Horizon 2020 framework with 12 industrial and academic partners aiming at aerogel particles from bio- and synthetic polymers. Biopolymer aerogels in particulate form have been reviewed recently. This mini-review focuses on the emerging field of particulate aerogels from synthetic polymers. That category includes mostly polyurea aerogels, but also some isolated cases of polyimide and phenolic resin aerogels. Particulate aerogels covered include powders, micro granules and spherical millimeter-size beads. For the benefit of the reader, in addition to the literature, some new results from our laboratory concerning polyurea particle aerogels are also included.
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Poly(urethane-norbornene) Aerogels via Ring Opening Metathesis Polymerization of Dendritic Urethane-Norbornene Monomers: Structure-Property Relationships as a Function of an Aliphatic Versus an Aromatic Core and the Number of Peripheral Norbornene Moieties. Molecules 2018; 23:molecules23051007. [PMID: 29693614 PMCID: PMC6102535 DOI: 10.3390/molecules23051007] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Revised: 04/13/2018] [Accepted: 04/21/2018] [Indexed: 11/16/2022] Open
Abstract
We report the synthesis and characterization of synthetic polymer aerogels based on dendritic-type urethane-norbornene monomers. The core of those monomers is based either on an aromatic/rigid (TIPM/Desmodur RE), or an aliphatic/flexible (Desmodur N3300) triisocyanate. The terminal norbornene groups (three at the tip of each of the three branches) were polymerized via ROMP using the inexpensive 1st generation Grubbs catalyst. The polymerization/gelation conditions were optimized by varying the amount of the catalyst. The resulting wet-gels were dried either from pentane under ambient pressure at 50 °C, or from t-butanol via freeze-drying, or by using supercritical fluid (SCF) CO2. Monomers were characterized with high resolution mass spectrometry (HRMS), 1H- and solid-state 13C-NMR. Aerogels were characterized with ATR-FTIR and solid-state 13C-NMR. The porous network was probed with N2-sorption and SEM. The thermal stability of monomers and aerogels was studied with TGA, which also provides evidence for the number of norbornene groups that reacted via ROMP. At low densities (<0.1 g cm−3) all aerogels were highly porous (porosity > 90%), mostly macroporous materials; aerogels based on the aliphatic/flexible core were fragile, whereas aerogels containing the aromatic/rigid core were plastic, and at even lower densities (0.03 g cm−3) foamy. At higher densities (0.2–0.7 g cm−3) all materials were stiff, strong, and hard. At low monomer concentrations all aerogels consisted of discrete primary particles that formed spherical secondary aggregates. At higher monomer concentrations the structure consisted of fused particles with the size of the previous secondary aggregates, due to the low solubility of the developing polymer, which phase-separated and formed a primary particle network. Same-size fused aggregates were observed for both aliphatic and aromatic triisocyanate-derived aerogels, leading to the conclusion that it is not the aliphatic or aromatic core that determines phase separation, but rather the solubility of the polymeric backbone (polynorbornene) that is in both cases the same. The material properties were compared to those of analogous aerogels bearing only one norbornene moiety at the tip of each branch deriving from the same cores.
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9
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Kucheyev SO, Lenhardt JM. Freezing Hydrogen in Nanoconfinement. FUSION SCIENCE AND TECHNOLOGY 2018. [DOI: 10.1080/15361055.2017.1392205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- S. O. Kucheyev
- Lawrence Livermore National Laboratory, Livermore, California 94550
| | - J. M. Lenhardt
- Lawrence Livermore National Laboratory, Livermore, California 94550
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10
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Braun T, Kim SH, Biener MM, Hamza AV, Biener J. Supercritical Drying of Wet Gel Layers Generated Inside ICF Ablator Shells. FUSION SCIENCE AND TECHNOLOGY 2017. [DOI: 10.1080/15361055.2017.1392203] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- Tom Braun
- Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, California 94550
| | - Sung Ho Kim
- Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, California 94550
| | - Monika M. Biener
- Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, California 94550
| | - Alex V. Hamza
- Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, California 94550
| | - Juergen Biener
- Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, California 94550
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11
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Kwasny MT, Zhu L, Hickner MA, Tew GN. Utilizing thiol–ene chemistry for crosslinked nickel cation‐based anion exchange membranes. ACTA ACUST UNITED AC 2017. [DOI: 10.1002/pola.28894] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Affiliation(s)
- Michael T. Kwasny
- Department of Polymer Science and EngineeringUniversity of Massachusetts Amherst, Amherst Massachusetts01003
| | - Liang Zhu
- Department of Materials Science and EngineeringThe Pennsylvania State University, University ParkPennsylvania16802
| | - Michael A. Hickner
- Department of Materials Science and EngineeringThe Pennsylvania State University, University ParkPennsylvania16802
| | - Gregory N. Tew
- Department of Polymer Science and EngineeringUniversity of Massachusetts Amherst, Amherst Massachusetts01003
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12
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Braun T, Walton CC, Dawedeit C, Biener MM, Kim SH, Willey TM, Xiao X, van Buuren A, Hamza AV, Biener J. In Situ Real-Time Radiographic Study of Thin Film Formation Inside Rotating Hollow Spheres. ACS APPLIED MATERIALS & INTERFACES 2016; 8:2600-2606. [PMID: 26717408 DOI: 10.1021/acsami.5b10357] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Hollow spheres with uniform coatings on the inner surface have applications in optical devices, time- or site-controlled drug release, heat storage devices, and target fabrication for inertial confinement fusion experiments. The fabrication of uniform coatings, which is often critical for the application performance, requires precise understanding and control over the coating process and its parameters. Here, we report on in situ real-time radiography experiments that provide critical spatiotemporal information about the distribution of fluids inside hollow spheres during uniaxial rotation. Image analysis and computer fluid dynamics simulations were used to explore the effect of liquid viscosity and rotational velocity on the film uniformity. The data were then used to demonstrate the fabrication of uniform sol-gel chemistry derived porous polymer films inside 2 mm inner diameter diamond shells.
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Affiliation(s)
- Tom Braun
- Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, California 94550, United States
| | - Christopher C Walton
- Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, California 94550, United States
| | - Christoph Dawedeit
- Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, California 94550, United States
| | - Monika M Biener
- Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, California 94550, United States
| | - Sung Ho Kim
- Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, California 94550, United States
| | - Trevor M Willey
- Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, California 94550, United States
| | - Xianghui Xiao
- Argonne National Laboratory, 9700 South Cass Avenue, Lemont, Illinois 60439, United States
| | - Anthony van Buuren
- Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, California 94550, United States
| | - Alex V Hamza
- Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, California 94550, United States
| | - Juergen Biener
- Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, California 94550, United States
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13
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Gu S, Li Z, Miyoshi T, Jana SC. Polybenzoxazine aerogels with controllable pore structures. RSC Adv 2015. [DOI: 10.1039/c5ra02635k] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Polybenzoxazine gelation is expedited in the presence of p-toluenesulfonic acid and the solid networks show strong dependence on the solvent.
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Affiliation(s)
- Senlong Gu
- Department of Polymer Engineering
- University of Akron
- Akron
- USA
| | - Zhen Li
- Department of Polymer Science
- The University of Akron
- Akron
- USA
| | | | - Sadhan C. Jana
- Department of Polymer Engineering
- University of Akron
- Akron
- USA
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14
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Herndon JW. The chemistry of the carbon-transition metal double and triple bond: Annual survey covering the year 2012. Coord Chem Rev 2014. [DOI: 10.1016/j.ccr.2014.02.026] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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15
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Two commercially available initiators for the retarded ring-opening metathesis polymerization of dicyclopentadiene. MONATSHEFTE FUR CHEMIE 2014. [DOI: 10.1007/s00706-014-1249-y] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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16
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Kim SH, Shin SJ, Lenhardt JM, Braun T, Sain JD, Valdez CA, Leif RN, Kucheyev SO, Wu KJJ, Biener J, Satcher JH, Hamza AV. Deterministic control over high-Z doping of polydicyclopentadiene-based aerogel coatings. ACS APPLIED MATERIALS & INTERFACES 2013; 5:8111-8119. [PMID: 23895541 DOI: 10.1021/am4021878] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
We report on simple and efficient routes to dope polydicyclopentadiene (PDCPD)-based aerogels and their coatings with high-Z tracer elements. Initially, direct halogenation of PDCPD wet gels and aerogels with elemental iodine or bromine was studied. Although several pathways were identified that allowed doping of PDCPD aerogels by direct addition of bromine or iodine to the unsaturated polymer backbone, they all provided limited control over the amount and uniformity of doping, especially at very low dopant concentrations. Deterministic control over the doping level in polymeric aerogels and aerogel coatings was then achieved by developing a copolymerization approach with iodine and tin containing comonomers. Our results highlight the versatility of the ring-opening metathesis polymerization (ROMP)-based copolymerization approach in terms of functionalization and doping of low density polymeric aerogels and their coatings.
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Affiliation(s)
- Sung Ho Kim
- Chemical Sciences Division, Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, California 94550, USA.
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