This book is intended for those who work on practical problems in the field of polymers and who are in need of orienting numerical information on polymer properties; for the organic chemist who is faced with the task of synthesizing new polymers and wonders if the structures he wants to realize will actually have the properties he has as a target; for the chemical engineer who is often forced to execute his designs without having enough data at his disposal and who looks in vain for numerical values of the quantities needed under the conditions of the process; for the polymer processer who tries to predict and understand how certain physical parameters will react to changes in process conditions; for the polymer technologist who tries to a get a better insight into the interrelations of the many disciplines in his branch; and finally for all students who are interested in the correlation between chemical structure and properties and in the mutual relation of the properties.

With the chemical constitution as the basis, our aim has consistently been to show that each functional group in the molecular structure actually performs a function that is reflected in all properties. Ample use has been made of the empirical fact that a number of quantities and combinations of quantities have additive properties – within certain limits of precision - so that these quantities can be calculated in a simple manner from empirically derived group contributions or increments. Many readers will be surprised to see how far one can get by setting out from this simple starting point. Theoretical expositions have purposely been omitted, except where some elucidation is indispensable for a proper understanding of quantities that are less widely known. It follows that this book has not been written for the polymer scientist proper, notably the polymer physicist and physical chemist, its design being too empirical for him and too much directed to practice. In this book the expert will find no data that are not available elsewhere. Many experts may even have great objections, some of them justified, to the design of this book and its approach.

Unfortunately, the gap between polymer scientists and practicians is not narrowing but constantly widening. The work in the field of polymer science is becoming increasingly sophisticated, in the experimental as well as in the theoretical disciplines. This book is meant to be a modest contribution towards narrowing the gap between polymer science and polymer practice. Time will have to show whether this attempt has been successful.