Foams are gas filled integral structures in which the gas is finely dispersed throughout acontinuouslyconnected solid phase. The bulk density is usually substantially lower than that of the solid component, and for the foams which form the focus for this book the volume fraction of the gas phase is considerably greater than 0.5 and in most instances in excess of 0.9. Many ofthe materials encountered in every day experience, such as bread, plants and trees, structural materials for buildings, comfort materials for domestic and automotive seating, shock absorbers or car bumpers and materials for noise control, have one thing in common - the cellular nature of their physical structure. Whyare thesestructuressoimportantin the naturaland man-made world? The reasons are both technical and commercial. From a technical viewpoint cellular materials offer: 1. high specific stiffness and strength - making them suitable for structural applications; 2. closeto idealenergymanagement - hencetheir useinthermalandacoustic insulation, vibration damping, acoustic absorption and shock mitigation; and 3. comfort - hence their use for domestic and automotive seating.

I am pleased to present the Fifth Edition of the Plastics Engineering Handbook. Last published in 1976, this version of the standard industry reference on plastics processing incorporates the numerous revisions and additions necessitated by 14 years of activity in a dynamic industry. At that last printing, then-SPI President Ralph L. Harding, Jr. anticipated that plastics pro duction would top 26 billion pounds in 1976 (up from 1.25 billion in 1947, when the First Edition of this book was issued). As I write, plastics production in the United States had reached almost 60 billion pounds annually. Indeed, the story of the U.S. plastics industry always has been one of phenomenal growth and unparalleled innovation. While these factors make compilation of a book such as this difficult, they also make it necessary. Thus I acknowledge all those who worked to gather and relate the information included in this 1991 edition and thank them for the effort it took to make the Plastics Engineering Handbook a definitive source and invaluable tool for our industry. Larry L. Thomas President The Society of the Plastics Industry, Inc.

Written in easy-to-read and -use format, this book provides a strong training resource and reference for product designers using plastics in their products – helping them identify, quantify, and confirm whether problems are related to product design or process. • Updates coverage of data analysis techniques and examples and expands coverage of failure analysis, key because of increased litigation related to product liability • Overviews plastic testing methods and the framework to investigate causes of plastic part failure • Provides a strong training resource and reference for product designers using plastics in their products • Features a video tour of a plastics testing labroatory on a companion website and has a separate manual of problems and solutions that are appropriate for college professors using the book as a class textbook