Dawn D. Dominguez

Bio: Dawn D. Dominguez is an academic researcher from United States Naval Research Laboratory. The author has contributed to research in topics: Phthalonitrile & Curing (chemistry). The author has an hindex of 20, co-authored 30 publications receiving 1599 citations.

Synthesis and properties of a bisphenol A based phthalonitrile resin

Abstract: A multiple aromatic ether linked phthalonitrile was synthesized and characterized. The oligomeric phthalonitrile monomer was prepared from the reaction of an excess amount of bisphenol A with 4,4'-difluorobenzophenone in the presence of K 2 CO 3 as the base in an N,N-dimethylformamide/toluene solvent mixture, followed by end capping with 4-nitrophthalonitrile in a two-step, one-pot reaction. The monomer properties were compared to those of the known resin 2,2-bis[4-(3,4-dicyanophenoxylphenyl]propane after being cured in the presence of bis[4-(4-aminophenoxy)-phenyllsulfone. Rheometric measurements and thermogravimetric analysis showed that the oligomeric phthalonitrile resin maintained good structural integrity upon heating to elevated temperatures and exhibited excellent thermal properties along with long-term oxidative stability. The ether-linked phthalonitrile resin absorbed less than 2.5% water by weight after exposure to an aqueous environment for extended periods.

Low-melting Phthalonitrile Oligomers: Preparation, Polymerization and Polymer Properties:

Abstract: A series of low-melting phthalonitrile oligomers were prepared in which variable-length multiple aromatic ether linkages interconnect the terminal phthalonitrile units These materials were designed to address the need for a processable resin system with good high-temperature properties The melt-processable oligomers are obtained using a modified-Ullman ether reaction between a bisphenol and a dihalobenzene to form a hydroxyl-terminated oligomeric intermediate that is endcapped by reaction with 4-nitrophthalonitrile Viscosity measurements show that the phthalonitrile oligomers are polymerized at a moderate temperature (200°C) using the typical aromatic diamine curing additives, bis[4-(4-aminophenoxy)phenyl]sulfone and 1,3-bis(3-aminophenoxy)benzene The oligomeric phthalonitrile/diamine mixtures exhibit a low complex melt viscosity (001-01 Pa s) at 200°C Differential scanning calorimetric analysis is used to follow the polymerization as the oligomeric phthalonitrile/diamine mixtures are heated to ele

Chemical detection with a single-walled carbon nanotube capacitor.

Abstract: We show that the capacitance of single-walled carbon nanotubes (SWNTs) is highly sensitive to a broad class of chemical vapors and that this transduction mechanism can form the basis for a fast, low-power sorption-based chemical sensor. In the presence of a dilute chemical vapor, molecular adsorbates are polarized by the fringing electric fields radiating from the surface of a SWNT electrode, which causes an increase in its capacitance. We use this effect to construct a high-performance chemical sensor by thinly coating the SWNTs with chemoselective materials that provide a large, class-specific gain to the capacitance response. Such SWNT chemicapacitors are fast, highly sensitive, and completely reversible.

Destruction and Detection of Chemical Warfare Agents

Abstract: 1. Scope of Article and Previous Related Reviews 5346 2. Introduction 5346 2.1. Destruction 5347 2.2. Sensing 5347 2.3. Historical Context 5348 2.3.1. Brief History and Molecular Structure 5348 2.4. Related Compounds and Nomenclature 5348 2.4.1. Phosphorus(V) Parent Compounds and Fundamental Chemistry 5348 2.4.2. Pesticides 5349 2.4.3. Simulants 5349 2.4.4. Decomposition Products 5350 2.5. Toxicology 5351 2.5.1. Acetylcholine Esterase (AChE) Inhibition 5351 2.5.2. Endocannabinoid System Activation 5352 2.6. Critical Needs To Decontaminate and Detect 5353 2.7. Treaties and Conventions 5354 3. Stockpile Destruction 5355 3.1. Agent Storage 5355 3.2. Protection Protocols and Logistics 5355 3.3. Background 5355 3.4. Methods Currently Employed 5355 3.4.1. Incineration 5355 3.4.2. Neutralization by Base Hydrolysis 5356 4. Decomposition Reactions 5357 4.1. Hydrolysis 5357 4.2. Autocatalytic Hydrolysis or Hydrolysis Byproducts 5358 4.3. Use of Peroxide 5359 4.4. Oxidation with Bleach and Related Reagents 5360 4.5. Alkoxide as Nucleophile 5360 4.5.1. Basic Media 5360 4.5.2. Metal-Catalyzed Reactions 5361 4.5.3. Metal-Assisted Reactions 5363 4.5.4. Biotechnological Degradation 5363 4.5.5. Cyclodextrin-Assisted Reactions 5370 4.6. Halogen as the Nucleophile 5370 4.6.1. Use of BrOx 5370 4.6.2. Use of Other Halogens 5371 4.6.3. Use of Group 13 Chelates 5371 4.7. Surface Chemistry 5371 4.7.1. Bare Metals and Solid Nanoparticles 5371 4.7.2. Metal Oxides 5371 4.7.3. Representative Elements 5372 4.7.4. d-Block (Groups 4 10) 5373 4.7.5. Solid Metal Oxides of Group 3 and the Lanthanides 5375 4.7.6. Porous Silicon and Related Systems 5375 4.7.7. Zeolites 5375 4.7.8. Comparative IR Data 5375 4.8. Other Types of Systems 5375 5. Decontamination 5376 5.1. Overview: Ability to React with All Types of Agents, Ease of Application, and Compatibility with Treated Objects 5376 6. Agent Fate and Disposal 5378 6.1. Indoor 5378 6.2. Concrete and Construction Surfaces 5378 6.3. Landfills 5379 7. Sensing and Detection 5379 7.1. Possible Metal Ion Binding Modes in Solution 5379 7.1.1. Early Reports of Phosph(on)ate [R3PdO 3 3 3M nþ] Interactions (R= Alkyl, Alkoxyl) 5380 7.1.2. Coordination Chemistry of Downstream Non-P-Containing Products of Decomposition 5380 7.2. Colorimetric Detection 5381 7.3. Chemiluminescence: Fluorescence and Phosphorescence 5382 7.3.1. Lanthanide-Based Catalysts 5382 7.3.2. Organometallic-Based Sensors 5382 7.3.3. Organic Design 5382 7.3.4. Biologically-Based Luminescence Detection 5382 7.3.5. Polymer and Bead Supports 5382 7.4. Porous Silicon 5383 7.5. Carbon Nanotubes 5383

Data analysis for electronic nose systems

Abstract: Electronic noses (e-noses) employ an array of chemical gas sensors and have been widely used for the analysis of volatile organic compounds. Pattern recognition provides a higher degree of selectivity and reversibility to the systems leading to an extensive range of applications. These range from the food and medical industry to environmental monitoring and process control. Many types of data analysis techniques have been used on the data produced. This review covers aspects of analysis from data normalisation methods to pattern recognition and classification techniques. An overview of data visualisation such as non-linear mapping and multivariate statistical techniques is given. Focus is then on the use of artificial intelligence techniques such as neural networks and fuzzy logic for classification and genetic algorithms for feature (sensor) selection. Application areas are covered with examples of the types of systems and analysis methods currently in use. Future trends in the analysis of sensor array data are discussed.