Polymeric Foams & Foam Technology - 2nd Edition (Book Review)

By Patrick A. Toensmeier, Consultant

Polymer foam is a large and diverse industry that touches almost every aspect of daily life. The material finds use in numerous items, from hot-drink cups and food containers to running shoes, furniture, automotive seating, and window frames. Few materials are as versatile or as widely used.

Compiling a text on as wide-ranging a topic as this is challenging, but Dr. Daniel Klempner and Dr. Vahid Sendijarevic have co-authored a book that is comprehensive, up-to-date, and readable. The 584-page Polymeric Foams and Foam Technology is the second edition of this title, which Klempner, affiliated with the University of Detroit Mercy, and Sendijarevic, of Troy Polymers Inc., originally published a decade ago. The new edition covers the basics of process technology, looks at the latest developments in chemistry, and includes advances in critical regulatory areas like blowing agents, combustibility, and solid-waste disposal. Written with input from 20 contributors, the book is primarily for scientists, engineers, and academics, yet is also useful for product marketers who must keep current with developments in foam technology.

The first three chapters present the basics of flexible, semi-flexible, and rigid polymer foams. The authors discuss foam densities; mechanical, physical, and chemical means of creating foam structures; process techniques for fabricating foam parts and products like slabstock; key industries and markets; and regulatory challenges on fronting the industry.

There are, of course, two basic categories of polymer foam: thermoplastic and thermoset. While the book is almost exclusively concerned with plastic foams, there is discussion of rubber materials, including chapters dedicated to latex and silicone foams. This provides readers with additional perspective on the industry and increases the value of the text. Klempner and Sendijarevic include graphs, equations, tables, and diagrams throughout the book to illustrate key points. These are detailed enough for scientists and engineers, yet can be understood by readers who don’t have a technical background.

Specific types of foam are covered in separate chapters beginning with chapter 4. These include: flexible and rigid polyurethane; polyisocyanurate; polystyrene; polyolefin; polyvinyl chloride; epoxy; latex; silicone; fluoropolymer; wood-flour composite; phenolic; and syntactic polymer (i.e., polymer with filler of hollow microspheres). While there are other types of polymer foams, these materials account for most applications. The format of each chapter varies, but basic information includes an introduction to the material, its structure and chemistry, details on foam formation and properties, applications, and a list of references for further study.

Of special note is inclusion of woodflour composite (WFC) foams. WFC is a small but rapidly growing segment of the market that offers advantages to fabricators. WFC is less expensive than most foam fillers; reduces wear and tear on process machinery versus conventional fillers and fibers; can have better properties than conventional fillers and fibers; and is a durable, lowmaintenance replacement for wood in some applications. The chapter on WFC foam, written by Chul B. Park of the University of Toronto, is an informative look at a relatively new foam technology.

The remaining chapters cover flame retardance and blowing agents. Contributor Roza M. Aseeva of the Institute of Biochemical Physics in Moscow, begins the chapter on flame retardants by noting that most fires worldwide occur in buildings and transportation where polymer products are concentrated. Decreasing the fire hazard of polymeric materials, including foams, is an important aspect of fire safety. Aseeva discusses a number of subjects relevant to the combustibility of polymer foams, and concludes with a look at recent advances in flame retardance. These include the use of polymers that are inherently flame retardant, fire-resistant coatings, and new additives like polymer/ceramic hybrid nanocomposites.

The chapter on blowing agents, by Fyodor A. Shutov and Donald P. Visco Jr., both of Tennessee Technological University, discusses the chemistry and properties of physical and chemical blowing agents. Shutov and Visco add perspective by examining the regulatory issues affecting blowing agents, and reviewing alternative materials with zero ozone-depletion potential. They make the point that while some alternative blowing agents are more evironmentally friendly than conventional blowing agents, many carry tradeoffs, and ultimately, scientists and engineers need to look at the entire properties’ spectrum of a blowing agent, including its insulation effectiveness, in determining its environmental impact.

The book concludes with appendices of Greek and Roman letters used in scientific notations and a listing of conversion factors used in describing foam properties. These appendices are useful, but brief. The authors might consider expanding them if a future edition is planned, and including a list of foam trade names and major chemical and product suppliers to the industry. Klempner and Sendijarevic have done a masterly job of developing an authoritative and readable text on a material that is an essential component of product performance. Polymeric Foams and Foam Technology remains a classic reference on an important segment of plastics fabrication.