This reference provides a fundamental and practical understanding of flow instabilities that occur during the flow and processing of polymer melts, as well as current and developing methods to prevent and eliminate flow instabilities in order to increase production throughput and enhance manufacturing efficiency. The book covers a wide range of materials, including the majority of commodity polymers that are processed as melts under numerous processing operations such as extrusion, injection molding, fiber spinning, and film blowing; it also addresses fundamental rheological considerations.

From the Preface: “...[I]t is natural to ask what is the rate limiting step for processing operations; why not run a given operation 20% faster? Quite frequently, the answer to this question concerns flow instabilities. As the polymeric material is processed in the molten state, it retains characteristics of both liquids and solids. The faster one processes it, the more solid like its response becomes; seemingly simple processing operations become intractably difficult and the polymer flow becomes `chaotic' and uncontrollable...”

Target Audience: Polymer rheologists, scientists, engineers, technologists and graduate students who are engaged in the field of polymer processing operations and need to understand the impact of flow instabilities.

Table of Contents:

Introduction — Overview of Processing Instabilities

Viscoelasticity and Basic Flows:

Elements of Rheology

Secondary Flow Instabilities

Wall Slip: Measurement and Modeling Issues

Melt Fracture and Related Phenomena:

Sharkskin Instability in Extrusion

Stick—Slip Instability

Gross Melt Fracture in Extrusion

Conventional Polymer Processing Additives

Boron Nitride Based Polymer Processing Aids

Applications:

Draw Resonance in Film Casting

Fiber Spinning and Flim Blowing Instabilities

Coextrusion Instabilities

Tiger Stripes: Instabilities in Injection Molding

Index