Characterization And Analysis Of Polymers By Gas Chromatography

Written primarily to help the polymer chemist in streamlining his analytical techniques.

Presents the methods used for characterization of polymers. In addition to theory and basic principles, the instrumentation and apparatus necessary for methods used to study the kinetic and thermodynamic interactions of a polymer with its environment are covered in detail. Some of the methods examined include polymer separations and characterization by size exclusion and high performance chromatography, inverse gas chromatography, osmometry, viscometry, ultracentrifugation, light scattering and spectroscopy.

Analytical Methods for Polymer Characterization presents a collection of methods for polymer analysis. Topics include chromatographic methods (gas chromatography, inverse gas chromatography, and pyrolysis gas chromatography), mass spectrometry, spectroscopic methods (ultraviolet-visible spectroscopy, infrared spectroscopy, Raman spectroscopy, and nuclear magnetic resonance), thermal analysis (differential scanning calorimetry and thermogravimetry), microscopy methods (scanning electron microscopy, transmission electron microscopy, and atomic force microscopy), and x-ray diffraction. The author also discusses mechanical and dynamic mechanical properties.

Physical and spectroscopic methods have been used jointly for characterization of polymers for at least four decades. Yet, new techniques permit increasingly refined determination of polymer chemistry and morphol ogy_ The correlation of this knowledge with physical properties of polymers is helpful to planned synthesis of new products. The most prominent spectroscopic techniques through the forties and fifties were infrared and ultraviolet spectroscopy. Nuclear magnetic resonance, electron spin resonance and MOssbauer spectroscopy started making sig nificant contributions to polymer chemistry in the early sixties. Still more recently fluorescence spectroscopy and laser Raman spectroscopy have become readily appli cable to polymers and are contributing significantly to the understanding of the relationship between polymer structure and properties. Determination of the distribution of monomer se quences by molecular size has become possible through combined gel permeation chromatography and spectroscopic analysis. Fragments of polymers from chemical break down or from pyrolysis are further fractionated and structurally analyzed. The relationship between the chemistry of polymers and performance can be determined from changes in chemical structure and orientation after curing, degradation, or physical or thermal manipulation of the polymers.

Readers will find many practical applications of pyrolysis-GC/MS as well as R&D usage in this newly revised and expanded edition. Detailed experimental descriptions for the identification of synthetic polymers and copolymers are included. This volume presents the current state of analytical pyrolysis, and contains full identification of several classes of polymers/copolymers and biopolymers that readers will find helpful. Structures and functions of various types of pyrolyzers are explored, as well as the results of the pyrolysis-gas chromatographic-mass spectrometric identification of synthetic polymers/copolymers and biopolymers at 700°C.Practical applications of this hyphenated technique, detailing the analysis of microplastics, failure analysis in the automotive industry and solutions for technological problems are provided. Numerous practical applications of pyrolysis-GC/MS, for industrial and R&D usage, will be of benefit to Chemists and Engineers, as well as for students of Chemistry and Polymer Sciences.

The main subject of this book is the characterization of plastics. To a high degree the properties of these polymers depend on the distribution of the molar mass and of other structural features, and small deviations frequently have a great effect. Therefore the characterization of polymers cannot be restricted to the determination of mean values but must yield information on these distributions. Using classical methods, the analytical fractionation of polymer homologues and structurally isomeric polymers is extremely time-consuming. Therefore, efficient chromatographic techniques are being increasingly employed in modern polymer characterization. In the first place, high-performance liquid chromatography is applied, in the form of size exclusion chromatography. It is also possible, however, to use other separation modes. More space is devoted to these other possibilities in this volume than is merited by their current range of applications, as the author believes that many separation problems will be solved by separation techniques of the non-exclusion type. Nevertheless, much emphasis is placed on size exclusion chromatography. Not only because of its current wide range of applications, but also because its relative importance, as a complement to other chromatographic techniques may even increase in the forthcoming years. This book is the first to cover all phenomena related to the above considerations. Starting with an introduction to basic liquid chromatography and to polymer science, it deals with the adsorption behaviour of polymers, with gradient techniques, with the kinetic band broadening in liquid chromatography, with instrumental features and packing materials. The book consists of four balanced sections and related information from about 1800 references is compiled in the tables. Some 250 figures and 30 tables will help give the reader a clear insight of the topics discussed. The book is aimed at helping the analyst or polymer chemist who is looking for information about chromatographic methods for the characterization of polymers.

This volume provides an overview of polymer characterization test methods. The methods and instrumentation described represent modern analytical techniques useful to researchers, product development specialists, and quality control experts in polymer synthesis and manufacturing. Engineers, polymer scientists and technicians will find this volume useful in selecting approaches and techniques applicable to characterizing molecular, compositional, rheological, and thermodynamic properties of elastomers and plastics.