Use of polymers in product design has continued to grow at a rate unrivalled by conventional materials such as metal, ceramics or glass. More polymeric materials are becoming available to the designer, and this Rapra Review Report highlights the need for caution in new design work, for careful use of new materials, and for awareness of the product environment.

Dr. Peter Lewis examines the modes of product failure (which include fracture, wear, distortion, chemical degradation, business failure) and shows how careful examination of a failed part can identify the cause of the failure. Factors such as product design, mould design, processing and materials selection can all play a part in the final performance of a plastic product. The author considers the problems caused by cystallisation within the polymer, by surface contamination, by the stress or strain frozen in during processing. Additives can bring additional problems; weak spots may be created by insufficient mixing and additive migration may lead to chemical degradation in another element of a product.

Product failures in particular application areas are reviewed: pipe and fittings (including PVC, PE and PB/acetal systems), storage tanks, and medical products (including catheters, joints, breast implants, heart valves and pumps). Throughout this review, the text is supplemented by case studies which highlight specific product failures. These provide a description of the faulty product and the conclusions of the resulting investigations. Such case studies provide vital design information for future product development.

Dr. Peter Lewis is a Senior Lecturer in Materials at the Open University. He has expanded his expertise as a chemist with experience in the fields of metallurgy and engineering. His consultancy work encompasses failure diagnosis and new product design, particularly concerned with thermoplastics and composites, and he is the author of more than 50 publications.

This review is accompanied by an indexed section containing more than 300 references and abstracts selected from the Polymer Library. These provide the reader with a valuable reference source for further information regarding the failure of plastic products.