On this, the dawning of a new age in high technology, man is seeking answers to increasingly complex problems. We are routinely launching reusable vehicles into space, designing and building computers with seemingly limitless powers, and developing sophisticated communications systems using laser technology, fiber optics, holography, etc., all of which require new and advanced materials. Polymer alloys continue to provide new solutions to the materials problems, and remain an area of ever increasing research. Polymer alloys are mu1ticomponent macromolecular systems. The components may be all on the same chain (as in block co polymers), on side chains (as in graft copolymers), or in different molecules (as in po1yb1ends and interpenetrating polymer networks). The variety of morphologies possible and the synergistic effects on ultimate properties continue to stimulate research on new polymer alloys. More and more studies on synthesis of new alloys, the kinetics and mecha nisms of their formation, and their characterization, are taking place, as well as studies on their processing and applications. This book presents the proceedings of the Symposium on Polymer Alloys, sponsored by the American Chemical Society's Division of OrganiC Coatings and Plastics Chemistry held at the 182nd meeting of the American Chemical Society in New York, in August, 1981. The most recent efforts of scientists and engineers from allover the world in this increasingly important field are presented in the following pages.

P. S. HOPE and M. J. FOLKES Mixing two or more polymers together to produce blends or alloys is a well-established strategy for achieving a specified portfolio of physical proper ties, without the need to synthesise specialised polymer systems. The subject is vast and has been the focus of much work, both theoretical and experimental. Much ofthe earlier work in this field was necessarily empirical and many ofthe blends produced were of academic rather than commercial interest. The manner in which two (or more) polymers are compounded together is of vital importance in controlling the properties of blends. Moreover, particular ly through detailed rheological studies, it is becoming apparent that process ing can provide a wide range of blend microstructures. In an extreme, this is exemplified by the in situ formation of fibres resulting from the imposition of predetermined flow fields on blends, when in the solution or melt state. The microstructures produced in this case transform the blend into a true fibre composite; this parallels earlier work on the deformation of metal alloys. This type of processing-structure-property correlation opens up many new possi bilities for innovative applications; for example, the production of stiff fibre composites and blends having anisotropic transport properties, such as novel membranes. This book serves a dual purpose.

Distinguishing among blends, alloys and other types of combinations, clarifying terminology and presenting data on new processes and materials, this work present up-to-date and effective compounding techniques for polymers. It offers extensive analyses on the challenging questions that surround miscibility, compatibility, dynamic processing, interaction/phase behaviour, and computer simulations for predicting behaviours of polymer mixture and interaction.

Modification of Polymer Properties provides, for the first time, in one title, the latest information on gradient IPNs and gradient copolymers. The book covers the broad range of polymer modification routes in a fresh, current view representing a timely addition to the technical literature of this important area. Historically, blends, copolymers, or filled polymers have been developed to meet specific properties, or to optimize the cost/properties relationship. Using the gradient structure approach with conventional radical polymerization, it has been shown that it is possible to optimize properties if appropriate gradients in the composition of copolymer chains are obtained. An overview of the gradient structure approach for designing polymers has not appeared in the recent literature and this title covers the different methods used to modify properties, offering the whole range of ways to modify polymers in just one volume and making this an attractive option for a wide audience of practitioners. The approach for each chapter is to explain the fundamental principles of preparation, cover properties modification, describe future research and applications as examples of materials that may be prepared for specific applications, or that are already in use, in present day applications. The book is for readers that have a basic background in polymer science, as well as those interested in the different ways to combine or modify polymer properties. - Provides an integrated view on how to modify polymer properties - Presents the entire panorama of polymer properties modification in one reference, covering the essential information in each topic - Includes the optimization of properties using gradients in polymers composition or structure

An introduction to polymer alloys and blends.

Written by an international group of highly respected contributors, this fundamental reference work covers all aspects of polymer blends: science, engineering, technology and applications.