G. Scott - Böcker

Few scientific developments in recent years have captured the popular imagination like the subject of'biodegradable' plastics. The reasons for this are complex and lie deep in the human subconscious. Discarded plastics are an intrusion on the sea shore and in the countryside. The fact that nature's litter abounds in the sea and on land is acceptable because it is biodegradable - even though it may take many years to be bioassimilated into the ecosystem. Plastics litter is not seen to be biodegradable and is aesthetically unacceptable because it does not blend into the natural environment. To the environmentally aware but often scientifically naive, biodegradation is seen to be the ecologically acceptable solution to the problem of plastic packaging waste and litter and some packaging manufacturers have exploited the 'green' consumer with exaggerated claims to 'environmentally friendly' biodegradable packaging materials. The principles underlying environmental degradation are not understood even by some manufacturers of 'biodegradable' materials and the claims made for them have been categorized as 'deceptive' by USA legislative authorities. This has set back the acceptance of plastics with controlled biodegradability as part of the overall waste and litter control strategy. At the opposite end of the commercial spectrum, the polymer manufactur­ ing industries, through their trade associations, have been at pains to discount the role of degradable materials in waste and litter management. This negative campaign has concentrated on the supposed incompatibility of degradable plastics with aspects of waste management strategy, notably materials recycling.

Combines a succinct style with an easy-to-use format to provide readers with a clear understanding regarding the principles and practice of bacteriology. Includes accessible information on bacteria as agents of human disease.

As environmental performance becomes increasingly important, the development of man-made polymers and their associated benefits has been overshadowed by problems relating to their ultimate disposal. In the light of wider acceptance of polymers for use in high technology applications, Polymers and the Environment aims to redress the balance. The book reviews the properties and industrial applications of polymers and discusses their environmental benefits compared with traditional materials. It also addresses the issues of polymer durability, recycling processes to aid waste minimization and biodegradable polymers. This text is intended to introduce the non-specialist reader to the benefits and limitations of polymeric materials from an environmental viewpoint, and will prove a useful book for both students and professionals.

To help address the challenges of sustainable development, higher education institutions must transform themselves, bringing together best practice in quality management for tertiary education with best practice in education for sustainable development. This book provides tested strategies and pathways for undertaking this successfully.

To help address the challenges of sustainable development, higher education institutions must transform themselves, bringing together best practice in quality management for tertiary education with best practice in education for sustainable development. This book provides tested strategies and pathways for undertaking this successfully.

The emphasis in degradable polymers has changed since the first edition of this text. Biomedical and agricultural applications remain important topics of scientific and commercial interest in the second edition - however, an increased emphasis on composting as a means of recovering value from wastes has led to a new impetus to understand how plastics degrade in the environment and the implication of this for international standards. Polymers based on renewable resources are also a major topic in this edition but the debate continues about their long-term sustainability and ecological advantages over degradable man-made polymers. This work should be of interest, not only to academic and industrial scientists working on packaging, agricultural and medical applications of plastics, but also to students of environmental science and legislators concerned with the effects of man-made materials in the environment.

The purpose of this publication is two-fold. In the first place it is intended to review progress in the development of practical stabilising systems for a wide range of polymers and applications. A complemen­ tary and ultimately more important objective is to accommodate these practical developments within the framework of antioxidant theory, since there can be little question that further major advances in the practice of stabilisation technology will only be possible on a firm mechanistic foundation. With the continual increase in the number of commercial anti­ oxidants and stabilisers, often functioning by mechanisms not even considered ten years ago, there is a need for a general theory which will allow the potential user to predict the performance of a particular antioxidant structure under specific practical conditions. Any such predictive tool must involve a simplified kinetic approach to inhibited oxidation and, in Chapter 1, Denisov outlines a possible mechanistic approach with the potential to predict the most useful antioxidant to use and the limits of its usefulness. In Chapter 2, Schwetlick reviews the current state of knowledge on the antioxidant mechanisms of the phosphite esters with particular emphasis on their catalytic peroxidolytic activity. Dithiophosphate v vi PREFACE derivatives show a similar behaviour but for quite different reasons and, in Chapter 3, AI-Malaika reviews information available from analytical studies, particularly using 31p_NMR spectroscopy, to elucid­ ate the complex chemistry that leads to the formation of the antioxidant -active agents.

The emphasis in degradable polymers has changed since the first edition of this book. Biomedical and agricultural applications remain important topics of scientific and commercial interest in the second edition. However, an increased emphasis on composting as a means of recovering value from wastes has led to a new impetus to understand how plastics degrade in the environment and the implication of this for international standards. Polymers based on renewable resources are also a major topic in this edition but the debate continues about their long-term sustainability and ecological advantages over degradable man-made polymers. Degradable Polymers will be of interest not only to academic and industrial scientists working on packaging, agricultural and medical applications of plastics but also to students of environmental science and legislators concerned with the effects of man-made materials in the environment.

Few scientific developments in recent years have captured the popular imagination like the subject of'biodegradable' plastics. The reasons for this are complex and lie deep in the human subconscious. Discarded plastics are an intrusion on the sea shore and in the countryside. The fact that nature's litter abounds in the sea and on land is acceptable because it is biodegradable - even though it may take many years to be bioassimilated into the ecosystem. Plastics litter is not seen to be biodegradable and is aesthetically unacceptable because it does not blend into the natural environment. To the environmentally aware but often scientifically naive, biodegradation is seen to be the ecologically acceptable solution to the problem of plastic packaging waste and litter and some packaging manufacturers have exploited the 'green' consumer with exaggerated claims to 'environmentally friendly' biodegradable packaging materials. The principles underlying environmental degradation are not understood even by some manufacturers of 'biodegradable' materials and the claims made for them have been categorized as 'deceptive' by USA legislative authorities. This has set back the acceptance of plastics with controlled biodegradability as part of the overall waste and litter control strategy. At the opposite end of the commercial spectrum, the polymer manufactur­ ing industries, through their trade associations, have been at pains to discount the role of degradable materials in waste and litter management. This negative campaign has concentrated on the supposed incompatibility of degradable plastics with aspects of waste management strategy, notably materials recycling.