Stabilization of Polymeric Materials

1 Principles of Oxidative Degradation.- 1.1 Introduction.- 1.2 Autoxidation.- 1.3 Diffusion and Solubility of Oxygen in Polymers.- 1.4 Degradation of Polymers During Processing in the Melt.- 1.4.1 Polypropylene.- 1.4.2 Polyethylene.- 1.4.3 Polystyrene.- 1.4.4 Polyamides and Polyesters.- 1.4.5 Polyacetals.- 1.4.6 Polycarbonate.- 1.4.7 Polyurethanes.- 1.4.8 High Performance Engineering Thermoplastics.- 1.4.9 Polymer Blends and Alloys.- 1.5 Upper Limit of Processing Temperature.- 1.6 Degradation of Polymers Under Long Term Thermal Conditions.- 1.7 Degradation of Polymers by Photooxidation.- 1.7.1 Absorption of Light by Polymers.- 1.7.2 Photochemistry of Hydroperoxides.- 1.7.3 Photo-Induced Reactions.- 1.7.4 Photo Degradation of Individual Substrates.- 1.7.4.1 Polyolefins.- 1.7.4.2 Polystyrene.- 1.7.4.3 Polyester.- 1.7.4.4 Polyamides.- 1.7.4.5 Polyacetal.- 1.7.4.6 Polycarbonate.- 1.7.4.7 Polyurethanes.- 1.7.4.8 High Performance Engineering Thermoplastics.- 1.7.4.9 Polymer Blends and Alloys.- 1.7.5 Oxidation Profile of a Sample’s Cross-Section.- 2 Principles of Stabilization.- 2.1 Stabilization Against Thermo-Oxidative Degradation.- 2.1.1 Inhibition of Autoxidation.- 2.1.2 H-Donors and Radical Scavengers.- 2.1.2.1 Phenolic Antioxidants.- 2.1.2.2 Aromatic Amines.- 2.1.2.3 Sterically Hindered Amines.- 2.1.2.4 Hydroxylamines.- 2.1.2.5 C-Radical Scavengers.- 2.1.3 Hydroperoxide Decomposers.- 2.1.3.1 Phosphites and Phosphonites.- 2.1.3.2 Organosulphur Compounds.- 2.1.4 Bifunctional Stabilizers.- 2.1.5 Blends of Stabilizers with Differing Functions.- 2.2 Stabilization Against Photooxidative Degradation.- 2.2.1 UV Absorbers.- 2.2.2 Quenchers.- 2.2.3 H-Donors and Radical Scavengers.- 2.2.3.1 Phenolic Antioxidants.- 2.2.3.2 Sterically Hindered Amines.- 2.2.3.3 Hydroxylamines.- 2.2.3.4 C-Radical Scavengers.- 2.2.4 Hydroperoxide Decomposers.- 2.2.5 Bifunctional Stabilizers.- 2.2.6 Blends of Stabilizers with Differing Functional Mechanisms.- Conclusions.- 3 Principles of Stabilization of Individual Substrates.- 3.1 Polyolefins.- 3.1.1 Melt Stability of Polyolefins.- 3.1.2 Long Term Thermal Stability of Polyolefins.- 3.1.3 Color Development in Polyolefins.- 3.1.4 Light Stability of Polyolefins.- 3.2 Thermoplastic Polyolefins (TPO).- 3.3 Elastomers.- 3.4 Styrenic Polymers.- 3.4.1 Polystyrene.- 3.4.2 Impact-Modified Polystyrene.- 3.4.3 Styrene/Acrylonitrile Copolymers.- 3.4.4 Acrylonitrile/Butadiene/Styrene Copolymers.- 3.5 Polyesters.- 3.6 Polyamides.- 3.7 Polyacetals.- 3.8 Polycarbonates.- 3.9 Polyurethane.- 3.10 High Performance Engineering Thermoplastics.- 3.11 Polymer Blends and Alloys.- 4 Influence of Metals, Fillers and Pigments on Stability.- 4.1 Metal Ion Deactivators.- 4.2 Fillers.- 4.3 Pigments.- 4.3.1 Non Colored Pigments.- 4.3.2 Color Pigments.- 5 Solubility and Diffusion of Stabilizers in Polymers.- 5.1 Solubility in Theory.- 5.2 Solubility in Practice.- Conclusions.- 5.3 Physical Loss of Stabilizers from Polymers Through Diffusion and Evaporation.- 5.3.1 Stabilizer Loss in Theory.- 5.3.1.1 Loss of Stabilizer by Evaporation.- 5.3.1.2 Loss of Stabilizer by Surface Precipitation.- 5.3.2 Diffusion in Practice.- Conclusions.- 5.3.3 Stabilizer Loss in Practice.- Conclusions.- 5.4 Service Lifetime Predictions for Polymer End Use Applications.- 5.4.1 Theoretical Considerations.- 5.4.2 Failure Criterion.- 6 Testing of Stabilizers in the Substrate.- 6.1 Introduction.- 6.2 Testing of Melt Stability.- 6.3 Testing of Long Term Thermal Stability.- 6.3.1 Oven Aging Techniques.- 6.3.2 Testing Under External Stress.- 6.3.3 High Pressure Oxygen Techniques.- 6.3.4 Oxygen Absorption Techniques.- 6.3.5 Chemiluminescence Techniques.- 6.4 Testing Light Stability of Polymers.- 6.4.1 Natural vs Artificial Weathering.- 6.4.2 Test Methods.- 6.5 Effect of Gamma Radiation on Polymers.- Conclusions.- 7 Outlook and Trends.- 7.1 New Substrates.- 7.1.1 Metallocene-Based Polymers.- 7.1.2 Engineering Thermoplastics.- 7.1.3 Polymer Blends and Alloys.- 7.2 Recycling of Polymers.- References.- Appendix 1.- List of Abbreviations and Symbols.- Chemical Symbols.- Physical Symbols.- Appendix 2.- Appendix 3.