Atmospheric Oxidation and Antioxidants, Vol. 2

556 Pages·1993·20.33 MB·English

Atmospheric Oxidation
and Antioxidants
VOLUME II
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Atmospheric
Oxidation and
Antioxidants
VOLUME II
G. Scotty editor
Department of Chemical Engineering
and Applied Chemistry
Aston University
Aston Triangle
Birmingham B4 7ET
U.K.
ELSEVIER
AMSTERDAM - LONDON - NEW YORK - TOKYO 1993
ELSEVIER SCIENCE PUBLISHERS B.V.
Sara Burgerhartstraat 25
P.O. Box 211, 1000 AE Amsterdam, The Netherlands
ISBN: 0-444-89615-5 (volume I)
0-444-89616-3 (volume II)
0-444-89617-1 (volume III)
0-444-89618-x (set)
© 1993 Elsevier Science Publishers B.V. All rights reserved.
No part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or by any
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Amsterdam, The Netherlands.
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products liability, negligence or otherwise, or from any use or operation of any methods, products, instructions
or ideas contained in the material herein.
This book is printed on acid-free paper.
Printed in The Netherlands.
V
CONTENTS
Preface ix
List of authors xi
CHAPTER 1. LUBRICATING OIL OXIDATION AND
STABILISATION, by T. Colclough 1
1. Introduction 1
2. Effect of Basestock Composition on Oxidation Stability 2
3. The Performance of Lubricants in Engines 11
4. Bench Oxidation Tests. Catalysis by Metals and Nitrogen Oxides . . 28
5. Actions and Interactions of Antioxidants 37
References 64
CHAPTER 2. DETERIORATION OF EDIBLE OILS AND
FOODSTUFFS, by S.P. Kochhar 71
1. Introduction 71
2. Food Oils and Fats 73
3. Types of Lipid Deterioration 77
4. Antioxidants and Mechanisms of Their Action 101
5. Concluding Remarks 123
References 123
Appendices 132
CHAPTER 3. OXIDATION AND STABILISATION OF POLYMERS
DURING PROCESSING, by Gerald Scott 141
1. The Significant of the Processing Operation 141
2. Mechanodegradation of Polymers „ 141
3. Chemical Plasticisation (Peptisation) of Rubbers 148
4. The Effect of Temperature during Mechanooxidation 150
5. Processing of Thermoplastic Polymers 151
6. Stabilisation of Polymers during Processing 161
7. Effect of Melt Stabilisers on Subsequent Environmental
Ageing 203
References ,. 213
VI
CHAPTER 4. THE PHYSICAL CHEMISTRY OF POLYMER
OXIDATION AND STABILIZATION, by N. C. Billingham 219
1. Introduction 219
2. Surface Heterogeneity of Polymer Oxidation 220
3. Macroscopic Heterogeneity of Oxidation 238
4. Molecular Heterogeneity of Oxidation 233
5. Solubility of Polymer Additives 231
6. Mobility of Polymer Additives 249
7. Loss of Additives from Polymers 255
8. Physical Effects in Accelerate Ageing 269
9. Conclusions 269
Acknowledgements 270
References 270
CHAPTER 5. MACROMOLECULAR AND POLYMER-BOUND
ANTIOXIDANTS, by Gerald Scott 279
1. Solubility, Diffusivity and Volatility of Antioxidants 279
2. Environmental Impact of Additives in Polymers 282
3. Effect of Processing on Antioxidant Effectiveness 284
4. Antioxidants Based on Large Molecules 286
5. Polymer-Bound Antioxidants 288
References 325
CHAPTER 6. METAL CATALYSED OXIDATION AND ITS
INHIBITION, byZ. Osawa 327
1. Introduction 327
2. General Features of the Role of Metallic Compounds 328
3. Examples of the Effects of Metallic Compounds on Degrada­
tion 333
4. Inhibition of Metal-Catalyzed Degradation 345
5. Conclusions 360
References 361
CHAPTER 7. OZONE DEGRADATION AND ANTIOZONANTS, by
R.P. Lattimer, R. W. Layer and C.K Rhee 363
1. Introduction 363
2. Chemistry of Ozone Attack 364
3. Physical Aspects in Ozone Cracking 366
4. Desirable Properties of Antiozonants 368
5. Hydrocarbon Waxes 369
6. Chemical Antiozonants 371
7. Mechanism of Action of Chemical Antiozonants 372
8. Manufacture and Production 376
9. Alternatives to Antiozonants 377
vii
10. Testing 378
11. Health and Safety Factors 380
12. Uses and Formulations 380
References 382
CHAPTER 8. PHOTODEGRADATION AND
PHOTOSTABILISATION, by Gerald Scott 385
1. Weathering of Polymers 385
2. Photodegradation and Biodegradation . . . 386
3. Photooxidation 387
4. Photolysis and Photooxidation 392
5. Stabilisation of Polymers Against the Effects of Light 403
References 424
CHAPTER 9. SYNERGISM AND ANTAGONISM, by Gerald Scott . . 431
1. Factors Affecting Antioxidant Performance 431
2. Synergistic Effects of Antioxidants and Stabilisers 432
3. Antagonism 454
References 457
CHAPTER 10. FIRE RETARDANT POLYMERIC MATERIALS, by
G. Camino 461
1. Introduction 461
2. Evaluation of Polymer Combustion 461
3. Fire Retardants 464
4. Inorganic Hydroxides 465
5. Halogen-Based Fire Retardants 467
6. Intumescent Systems 476
7. Conclusions 489
References 489
Appendix 493
CHAPTER 11. DEGRADATION AND STABILISATION OF
POLYMERS SUBJECTED TO HIGH ENERGY RADIATION, by
D.J. Carlsson 495
1. Introduction 495
2. Primary Radiation Processes in Polymers 498
3. Secondary Reactions in Irradiated Polymers 499
4. Inhibition of Radiation Degradation Reactions 511
5. γ-Stabilisation and Radiolysis Reactions 528
References 529
Subject Index 531
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PREFACE
Oxidation by molecular oxygen is one of the most practically important of
all chemical processes. It is the basis of energy production in animals and,
at the same time, a major cause of irreversible deterioration and ultimate
death. Man uses oxygen positively in the production of energy by combus­
tion, and many important industrial processes in the petrochemical in­
dustry are based on the controlled oxidation of hydrocarbons. At the same
time, oxidation is the main cause of deterioration of foodstuffs and of many
industrial polymers.
It is clearly of great practical importance that the mechanisms of oxida­
tion and its prevention should be understood in order to utilise the reactions
of oxygen more effectively but, equally importantly, to control the adverse
effects of oxygen on man-made products and in biological systems. The three
volumes of this work are directed toward these objectives. Volume I reviews
current understanding of autoxidation, largely on the basis of the reactions
of oxygen with characterised chemicals. From this flows the modern mech­
anisms of antioxidant action and their application in stabilisation technol­
ogy. Volume II examines the oxidation chemistry of carbon-based materials
in more detail with emphasis on the technological phenomena that result
from the attack of oxygen and the practical procedures developed to prevent
them. Volume III addresses our present understanding of how oxidation is
involved both positively and negatively in life processes. This is a more
recent and rapidly developing aspect of oxidation chemistry and many of the
concepts still have to be proved by rigorous scientific investigation. Never­
theless, the mechanistic principles developed as a result of studies in vitro
over the years now provide the basis for understanding the complex oxida­
tion chemistry of life processes and its control by biological antioxidants.
The three volumes, although complementary to one another, form a single
whole and it is hoped that, by frequent cross-reference, the reader will be
enabled to utilise ideas and experience from other disciplines to enlighten
his own. The first edition of this work was published a quarter of a century
ago in a single volume. The increase in size of the second edition reflects the
growth of interest in the subject in the intervening period. Nevertheless, the
mechanisms outlined in the first edition still form the basis of our present
understanding of oxidation chemistry and there will therefore be frequent
reference to it in this edition.
GERALD SCOTT