Energetic Materials (eBook)

Manoj Shukla is Computational Chemistry Team Leader at the Environmental Laboratory, US Army Engineer Research and Development Center, Vicksburg, MS, USA. Veera M. Boddu is the Research Leader of the Plant Polymer Research Unit (PPL) at the National Center for Agriculture Utilization Research (NCAUR), Agriculture Research Service, US Department of Agriculture, ARS/USDA, 1815 N. University St., Peoria, IL  61604, USAJeffery Steevens is a Research Toxicologist at the U.S. Geological Survey, Columbia Environmental Research Center, Columbia, MO, USA.Damavarapu Reddy is Research Chemist at the U.S. Army Armament Research, Development, and Engineering Center, Picatinny, NJ, USA.Jerzy Leszczynski is a Professor of Chemistry and President's Distinguished Fellow at the Jackson State University, Jackson, MS, USA. 

Preface 6
Contents 8
1 High Performance, Low Sensitivity: The Impossible (or Possible) Dream? 10
Abstract 10
1 The Problem 10
2 Detonation Performance 11
2.1 Measurement 11
2.2 Some Governing Factors 12
3 Sensitivity 14
3.1 Measurement 14
3.2 Some Governing Factors 15
4 An Apparent Dilemma 23
5 In Quest of the Impossible Dream 26
5.1 Molecular Dimensions 26
5.2 Molecular Framework 27
5.3 Molecular Stoichiometry 27
5.4 Amino Substituents 27
5.5 Molecular Structural Modifications 28
6 Final Remarks 29
References 29
2 Recent Advances in Gun Propellant Development: From Molecules to Materials 32
Abstract 32
1 Gun Propellant Ballistics in a Nutshell 32
2 Ignition of Propellants 35
3 Combustion of Propellants 37
4 Propellant Ingredients 42
4.1 Energetic Molecules 42
4.2 Energetic Binders 43
4.3 Energetic Plasticizers 46
4.4 Energetic Fillers 52
4.4.1 High Nitrogen Content (HNC) Energetic Materials and Polynitrogen 53
4.4.2 Nanomaterials 57
4.4.3 Co-crystalization 59
5 Low Weight Percentage Additives 61
6 Propellant Formulation Modeling and Design 63
7 Processing Effects 66
8 Summary 69
References 69
3 How to Use QSPR Models to Help the Design and the Safety of Energetic Materials 75
Abstract 75
1 Introduction 75
2 Quantitative Structure-Property Relationships 76
2.1 Principle 76
2.2 Validation of QSPR Models 78
2.3 Robust Use of QSPR Models 80
3 Short Overview of QSPR Models for Energetic Materials 80
3.1 Detonation Properties 81
3.2 Brisance 82
3.3 Density 83
3.4 Heat of Formation 83
3.5 Melting Point 84
3.6 Sensitivity 85
3.7 Thermal Stability 87
4 Case Study: QSPR Models to Predict the Impact Sensitivity of Nitro Compounds 88
5 How to Use of QSPR Models for Energetic Materials 90
5.1 Use of QSPR Models in Regulatory Context 90
5.2 Use of QSPR Models for the Design of New Energetic Materials 92
6 Conclusions and Challenges 95
References 96
4 Energetic Polymers: Synthesis and Applications 99
Abstract 99
1 Introduction 99
2 Non-crosslinkable Energetic Binders 100
2.1 Nitrocellulose 100
2.2 Poly(vinyl nitrate) 102
2.3 Energetic Polyesters, Polyamides and Polyurethanes 102
2.4 Energetic Polyacrylates 104
2.5 Polynitrophenylene (PNP) 104
2.6 Nitramine Polymers 104
2.7 Poly(phosphazene)s 106
3 Crosslinkable Non-energetic Binder Systems for Propellant Formulations 109
3.1 Polysulfides 109
3.2 Polybutadienes with Carboxyl Functional Groups 110
3.3 Polyurethanes and Hydroxy-Terminated Polybutadiene (HTPB) 111
3.4 Nitrated HTPB 112
3.5 Cyclodextrin Nitrate (CDN) 112
4 Development of Binder Systems in Explosive Formulations 114
5 Oxirane-Based Crosslinkable Energetic Polymers 115
5.1 Poly(glycidyl nitrate) (PGN) 116
5.2 End-Group Modification of Poly(glycidyl nitrate) 119
5.3 Glycidyl Azide Polymer (GAP) 121
5.4 Variants of Glycidyl Azide Polymer (GAP) 123
5.5 Other Oxirane-Based Energetic Polymers 124
6 Oxetane-Based Energetic Polymers 126
6.1 Ring-Substituted Oxetanes 126
6.2 Methyl-Substituted Oxetanes 128
6.3 Energetic Thermoplastic Elastomers (ETPE’s) 130
References 137
5 Pyrophoric Nanomaterials 143
Abstract 143
1 Introduction 143
2 Nanoscale Powders 144
2.1 Introduction 144
2.2 Aluminum Nanopowder 146
2.3 Iron Nanopowder 148
3 Milled Powders 149
3.1 Introduction 149
3.2 Mechanism 150
3.3 Process Control 152
3.3.1 Types of Mills 152
3.3.2 Selection of Raw Materials 153
3.3.3 Time and Intensity 154
3.3.4 Process Control Agents 154
3.3.5 Media 154
3.3.6 Atmosphere 155
3.3.7 Contamination 155
3.4 Tunability 156
4 Coating/Substrates 158
4.1 Introduction 158
4.2 Substrate/Structure Production Techniques 159
4.2.1 Chemical Leaching 159
4.2.2 Sol-Gel Techniques 160
4.2.3 Filtration 162
4.2.4 Tape Casting 163
4.2.5 Cold Isostatic Pressing 164
4.3 Dynamic Combustion Characteristics 164
4.3.1 Carbon-Based Substrates 164
4.3.2 Iron/Ceramic Composite Substrates 165
4.3.3 Iron/Ceramic Composite Structures 165
4.4 Tunability Through Addition of Tertiary Reactives 167
5 Pyrophoric Foams 167
5.1 Introduction 167
5.2 Metallic Foams 168
5.3 Metallic Composite Foams 171
6 Safety Considerations 173
6.1 Safety, Handling, and Characterization 173
7 Conclusions 176
References 176
6 The Relationship Between Flame Structure and Burning Rate for Ammonium Perchlorate Composite Propellants 179
Abstract 179
1 Introduction and Background 180
2 Flame Structure Models 183
3 Research Methods 185
3.1 Linear Burning Rate Measurements 185
3.2 Optical Emission and Transmission 186
3.3 Laser Induced Fluorescence 187
4 Formulation Effect on Flame Structure 188
4.1 Counterflow Diffusion Flames 189
4.2 Ported Pellets 190
4.3 Sandwich/Lamina 191
4.4 Monomodal 195
4.5 Bimodal 200
4.5.1 Coarse-to-Fine Ratio 200
Global Burning Rate 200
Flame Structure 202
Coarse Crystal Burning Characteristics 205
4.5.2 Catalysts 206
4.5.3 Binder 209
4.5.4 Aluminum 210
5 Predicted Flame Structures 211
6 Conclusions 213
References 216
7 PAFRAG Modeling and Experimentation Methodology for Assessing Lethality and Safe Separation Distances of Explosive Fragmentation Ammunitions 220
Abstract 220
1 Introduction: Fragmentation of Explosively Driven Shells 220
2 The Fragmentation Arena Test Methodology 224
3 The PAFRAG Fragmentation Model 225
4 The PAFRAG-Mott Fragmentation Model 227
5 PAFRAG-Mott Model Validation: Charge a Analyses 231
6 Charge B Modeling and Experimentation 236
7 Charge C Modeling and Experimentation 240
8 Charge C PAFRAG Model Analyses: Assessment of Lethality and Safety Separation Distance 245
9 Summary 246
Acknowledgements 246
References 246
8 Grain-Scale Simulation of Shock Initiation in Composite High Explosives 249
Abstract 249
1 Introduction 249
2 Multi-crystal Simulations 251
2.1 Microstructure Characterization and Reconstruction 252
2.2 Survey of HE Shock Initiation Work 253
3 Single-Crystal Simulations 257
3.1 Continuum Model of HMX 258
3.1.1 Solid Phase 258
3.1.2 Fluid Phases 260
3.1.3 Thermal Properties 260
3.1.4 Chemistry 260
3.2 Simulations of Intragranular Pore Collapse 262
3.2.1 Basic Results for a Reference Case 263
3.2.2 Heat Conduction Considerations 266
3.2.3 Model Sensitivity to Solid Flow Strength 267
3.2.4 Model Sensitivity to Liquid Viscosity 269
4 Concluding Remarks 271
Acknowledgements 273
References 273
9 Computational Modeling for Fate, Transport and Evolution of Energetic Metal Nanoparticles Grown via Aerosol Route 277
Abstract 277
1 Introduction 278
1.1 Energetic Nanomaterials: A Broad Overview 278
1.2 Modeling Work to Study Fate, Transport and Growth of Metal Nanoparticles 280
2 Homogeneous Gas-Phase Nucleation of Metal Nanoparticles 282
2.1 Classical Nucleation Theory (CNT) 285
2.2 Modeling Nucleation: KMC Based Model and Deviations from CNT 289
3 Non-isothermal Coagulation and Coalescence 295
3.1 Mathematical Model and Theory 298
3.1.1 Smoluchowski Equation and Collision Kernel Formulation 298
3.1.2 Energy Equations for Coalescence Process 299
3.1.3 Effect of Lowered Melting Point of Nanoparticles on Coalescence 303
3.1.4 Radiation Heat Loss Term for Nanoparticles: A Discussion 305
3.2 Modeling Non-isothermal Coagulation and Coalescence: Coagulation Driven KMC Model 305
3.2.1 Implementation of MC Algorithm: Determination of Characteristic Time Scales for Coagulation 307
3.2.2 Model Metrics and Validation for the KMC Algorithm 309
3.3 Results and Discussions: Effects of Process Parameters on Nanoparticle Growth via Coagulations and Non-isothermal Coalescence 311
3.3.1 Effect of Background Gas Temperature 311
3.3.2 Effect of Background Gas Pressure 313
3.3.3 Effect of Volume Loading 317
4 Surface Oxidation 317
4.1 Mathematical Model and Theory 320
4.1.1 Morphology: Surface Fractal Dimension 320
4.1.2 Collision Kernel and Characteristic Collision Time 320
4.1.3 Coalescence 324
4.1.4 Surface Oxidation: Transport Model and Species Balance 324
4.1.5 Energy Balance 330
4.2 Modeling Surface Oxidation: Coagulation Driven KMC Model 331
4.3 Effect of Morphology and Non-isothermal Coalescence on Surface Oxidation of Metal Nanoparticles: Results from the Study 332
4.3.1 Estimation of Primary Particle Size 332
4.3.2 Estimation of Particle Morphology 333
4.3.3 Surface Oxidation and Evolution of Fractal-like Al/Al2O3 Nanoparticles 335
4.3.4 Implications of Coalescence-Driven Fractal like Morphology on the Surface Oxidation of Al/Al2O3 Nanoparticles 339
5 Conclusion 340
Acknowledgements 341
References 341
10 Physical Properties of Select Explosive Components for Assessing Their Fate and Transport in the Environment 348
Abstract 348
1 Introduction 349
2 Model Predictions 352
2.1 Physical Properties Prediction Using Estimation Programs Interface (EPI) Suite 352
2.2 Physical Properties Prediction Using SPARC Performed Automated Reasoning in Chemistry (SPARC) Package 355
2.3 Theoretical Background for SPARC Approach for Calculating Physical Properties 356
2.4 SPARC approach for estimation of Water Solubility (Sw) and Activity Coefficient (?) 357
2.5 SPARC Approach for Estimation of Vapor Pressure (VP) 357
2.6 SPARC Approach for Estimation of Boiling Point (BP) 358
2.7 SPARC Approach for Estimation of Octanol-Water Partition Coefficient (Kow) 358
2.8 SPARC Approach for Estimation of Henry’s Law Constant (KH) 359
2.9 SPARC Approach for Estimation of Enthalpy of Vaporization (?Hvap) 359
3 Group Contribution and COSMOtherm Approach 359
4 Experimental Approaches 361
4.1 Experimental Approach For Measuring Octanol-Water Partition Coefficient (Kow) 361
4.2 Vapor Pressure (VP) 362
5 Conclusion 365
Acknowledgements 373
References 374
11 High Explosives and Propellants Energetics: Their Dissolution and Fate in Soils 377
Abstract 377
1 Introduction 379
2 Field Deposition 380
2.1 Propellants 381
2.2 High Explosives 382
3 Dissolution of Energetic Compounds 386
3.1 Propellants 386
3.2 High Explosives 390
4 Physicochemical Properties of Explosive and Propellant Constituents 393
5 Soil Interactions 394
5.1 TNT, DNT and Their Transformation Products 394
5.2 RDX and HMX 399
5.3 Nitroglycerine 399
5.4 Nitroguanidine 400
5.5 Reactive Transport 400
5.6 Conclusions 405
Acknowledgements 405
References 406
12 Insensitive Munitions Formulations: Their Dissolution and Fate in Soils 411
Abstract 411
1 Introduction 411
2 Field Deposition 413
3 Dissolution of IM Detonation Residues 417
3.1 Indoor Drip Tests 417
3.2 Outdoor Dissolution Tests 418
3.3 Mass Balance for Outdoor Tests 422
3.4 Photo-Transformation of IM 424
3.5 PH of the IM Solutions 426
4 Physiochemical Properties of Insensitive Munitions Formulations 427
5 Soil Interactions 428
5.1 Batch Soil Adsorption Studies 430
5.1.1 NTO 430
5.1.2 DNAN 434
5.2 Solution Transport for NTO and DNAN and HYDRUS-1D Modeling Results 437
5.3 Dissolution and Transport of IM Formulations 440
6 Summary 443
References 444
13 Toxicity and Bioaccumulation of Munitions Constituents in Aquatic and Terrestrial Organisms 448
Abstract 448
1 Introduction 449
2 Toxicity to Soil Microorganisms and Invertebrates 450
3 Toxicity to Terrestrial Plants 456
4 Toxicity to Aquatic Autotrophs 460
5 Toxicity to Tadpoles and Fish 460
6 Toxicity to Aquatic Invertebrates in Aqueous Exposures 461
7 Toxicity of Photo-Transformation Products 469
8 Toxicity to Aquatic Invertebrates and Fish in Exposures to Spiked Sediment 469
9 Bioaccumulation in Soil Invertebrates and Terrestrial Plants 471
9.1 Bioaccumulation in Fish and Aquatic Invertebrates 472
10 Summary and Conclusions 472
References 474
Index 483