Polymers and Electromagnetic Radiation E-Book

Wolfram Schnabel

• Herausgeber: Wiley-VCH
• Kategorie: Wissenschaft und neue Technologien
• Sprache: Englisch

Seitenzahl: 497

Veröffentlichungsjahr: 2014

Beschreibung

This first book to cover the interaction of polymers with radiation from the entire electromagnetic spectrum adopts a multidisciplinary approach to bridge polymer chemistry and physics, photochemistry, photophysics and materials science. The text is equally unique in its scope, devoting equal amounts of attention to the three aspects of synthesis, characterization, and applications. The first part deals with the interaction of polymers with non-ionizing radiation in the frequency-range from sub-terahertz via infrared radiation to visible and ultraviolet light, while the second covers interaction with ionizing radiation from the extreme ultraviolet to X-ray photons. The result is a systematic overview of how both types of radiation can be used for different polymerization approaches, spectroscopy methods and lithography techniques. Authored by a world-renowned researcher and teacher with over 40 years of experience in the field, this is a highly practical and authoritative guide.

Leseprobe

Contents

Cover

Related Titles

Title Page

Copyright

Preface

Introduction

Part I: Non-Ionizing Radiation

Chapter 1: Sub-Terahertz Radiation Including Radiofrequency (RF) and Microwave Radiation

1.1 Absorption

1.2 Applications in Polymer Chemistry

1.3 Applications in Polymer Physics

1.4 Industrial Applications

References

Chapter 2: Infrared Radiation

2.1 Absorption

2.2 Applications

2.3 Polymer Characterization by Two-Dimensional IR Spectroscopy

2.4 Time-Resolved Measurements in the mid-IR Range

2.5 Time-Resolved THz Spectroscopy

2.6 THz Optics Made From Polymers

References

Chapter 3: Visible and Ultraviolet Light

3.1 Absorption

3.2 Applications

3.3 Technical Developments

References

Part II: Ionizing Radiation

Chapter 4: Elementary Processes of the Interaction of High-Energy Photons with Matter

4.1 General Aspects

4.2 Attenuation Coefficients

4.3 Photoelectric Effect

4.4 Compton Scattering

4.5 Electron–Positron Pair Production

4.6 Photonuclear Absorption

4.7 Absorption of Swift Electrons

References

Chapter 5: Chemical Reactions Induced by High-Energy Radiation

5.1 General Aspects

5.2 Polymer Synthesis

5.3 Radiolysis of Bulk Synthetic Polymers

5.4 Radiolysis of Bulk Biopolymers

5.5 Radiolysis of Polymers in Solution

5.6 Technical Developments

References

Chapter 6: Applications of High-Energy Radiation in Polymer Physics

6.1 General Aspects

6.2 X-Ray Spectroscopy

6.3 X-Ray Imaging and Microscopy

6.4 X-Ray Scattering

References

Index

Related Titles

Theato, P., Klok, H. (eds.)

Functional Polymers by Post-Polymerization Modification

Concepts, Guidelines, and Applications

2013

ISBN: 978-3-527-33115-4, also available in digital formats

Thomas, S., Durand, D., Chassenieux, C., Jyotishkumar, P. (eds.)

Handbook of Biopolymer-Based Materials

From Blends and Composites to Gels and Complex Networks

2013

ISBN: 978-3-527-32884-0, also available in digital formats

Barner-Kowollik, C., Gruendling, T., Falkenhagen, J., Weidner, S. (eds.)

Mass Spectrometry in Polymer Chemistry

2012

ISBN: 978-3-527-32924-3, also available in digital formats

Mascia, L.

Polymers in Industry from A to Z

A Concise Encyclopedia

2012

ISBN: 978-3-527-32964-9, also available in digital formats

Yang, X. (ed.)

Semiconducting Polymer Composites

Principles, Morphologies, Properties and Applications

2012

ISBN: 978-3-527-33030-0, also available in digital formats

Schlüter, D.A., Hawker, C., Sakamoto, J. (eds.)

Synthesis of Polymers

New Structures and Methods

2012

ISBN: 978-3-527-32757-7, also available in digital formats

Makuuchi, K., Cheng, S.

Radiation Processing of Polymer Materials and itsIndustrial Applications

2012

ISBN: 978-0-470-58769-0, also available in digital formats

Knoll, W., Advincula, R.C. (eds.)

Functional Polymer Films

2 Volume Set

2011

ISBN: 978-3-527-32190-2, also available in digital formats

Leclerc, M., Morin, J. (eds.)

Design and Synthesis of Conjugated Polymers

2010

ISBN: 978-3-527-32474-3, also available in digital formats

Allen, N.S. (ed.)

Photochemistry and Photophysics of Polymer Materials

2010

ISBN: 978-0-470-13796-3, also available in digital formats

Matyjaszewski, K., Müller, A.H. (eds.)

Controlled and Living Polymerizations

From Mechanisms to Applications

2009

ISBN: 978-3-527-32492-7, also available in digital formats

All books published by Wiley-VCH are carefully produced. Nevertheless, authors, editors, and publisher do not warrant the information contained in these books, including this book, to be free of errors. Readers are advised to keep in mind that statements, data, illustrations, procedural details or other items may inadvertently be inaccurate.

Library of Congress Card No.: applied for

British Library Cataloguing-in-Publication Data

A catalogue record for this book is available from the British Library.

Bibliographic information published by the Deutsche Nationalbibliothek

The Deutsche Nationalbibliothek lists this publication in the Deutsche Nationalbibliografie; detailed bibliographic data are available on the Internet at <http://dnb.d-nb.de>.

© 2014 Wiley-VCH Verlag GmbH & Co. KGaA, Boschstr. 12, 69469 Weinheim, Germany

All rights reserved (including those of translation into other languages). No part of this book may be reproduced in any form – by photoprinting, microfilm, or any other means – nor transmitted or translated into a machine language without written permission from the publishers. Registered names, trademarks, etc. used in this book, even when not specifically marked as such, are not to be considered unprotected by law.

Print ISBN: 978-3-527-33607-4

ePDF ISBN: 978-3-527-67774-0

ePub ISBN: 978-3-527-67773-3

Mobi ISBN: 978-3-527-67772-6

oBook ISBN: 978-3-527-67771-9

Preface

In 2006, the author completed a first monograph on the interaction of radiation with the vast family of polymers; this was titled Polymers and Light. Fundamentals and Technical Applications. The completion of that work coincided with the idea of a new project, this time covering the whole range of electromagnetic radiation, from sub-radiofrequency waves of only a few Hertz to gamma rays of some 1022 Hertz. Again, the objective was to cover in a concise manner the leading-edge results of the research community from a single author's perspective. This book, Polymers and Electromagnetic Radiation, is the result of that project.

It is the intention of the author to provide the reader with a guided tour through the panorama of polymers and their interactions with electromagnetic waves of different frequencies and wavelengths. Wherever needed, the reader is introduced to the basic physical and chemical concepts involved. Throughout all chapters, the book demonstrates how scientific results find their way into both industrial applications and further research.

To obtain an overview of a subject as immense as the present one requires a lot of reading. After all, the more than 800 citations compiled separately at the end of each chapter are only a fraction of the literature that had to be searched in order to obtain a representative impression of what the state-of-the art research is seeking. But, reading takes time, and after six years of work the project became a race against time for several reasons. First, as leading-edge technology ever advances, the work of a reviewer resembles the task of the well-known Sisyphos who, in Hades, was required to push the same huge bolder up a hill, again and again. Second, unlike the eternal setting in mythology, time is limited on Earth and this is felt even more strongly by a retired researcher. In fact, shortly after the studies and the text edition for this book were completed, my father's reading ability was impaired by a mini-stroke, and this is why he asked me to write this preface and handle the further printing of the book.

It is therefore in his name that I refer to the people supporting his work. Special thanks go to M. Wiencken, senior librarian of the Helmholtz-Zentrum Berlin für Materialien und Energie (HZB). The smooth and professional support by the personnel of the publisher, Wiley-VCH, is also gratefully acknowledged.

Munich, September 2013R. Florian Schnabel

Introduction

This book concentrates on the interaction of electromagnetic waves with polymers and deals only exceptionally with particle radiation. Electromagnetic waves comprise a very broad range of frequencies that extends over more than 20 orders of magnitude from the radiofrequency region up to the region of hard γ-rays emitted from radionuclides or being part of the cosmic rays (see Table I.1).

Table I.1 Electromagnetic waves.

The various effects observed when electromagnetic radiation interacts with matter are interpreted on the basis of the so-called wave-particle duality; that is, electromagnetic radiation is considered to have both a wave-like and a particle-like character. Certain phenomena such as diffraction or interference can be interpreted only with the aid of the wave model, whereas energetic processes involving atoms or molecules such as absorption and emission can be understood only on the basis of the photon or quantum model. The particles of electromagnetic radiation are called photons, and the photon energy E is related to the frequency ν according to (Eq. I.1):

(I.1)

where h = 6.626 × 10−34 J s (6.626 × 10−31 g m2 s−1) denotes Planck's constant. According to Einstein, a photon of energy E has the quality of mass m according to Eq. (I.2)

(I.2)

where c = 3 × 108 m s−1 and denotes the velocity of electromagnetic radiation in free space.

Polymers are substances composed of macromolecules – that is, large molecules in excess of about 1000 atoms – and in many cases consist of long chains made up of small repeating units. Certain synthetic polymers are prepared via the polymerization of monomers and play important and ubiquitous roles in everyday life as plastic materials. Moreover, many biopolymers produced by living organisms are fundamental to biological functions.

Electromagnetic radiation can interact with matter – including polymers – in a variety of ways, the most prominent interaction modes being absorption and scattering. Radiation of frequencies below 1012 Hz (1 THz) is absorbed by polymers containing polar groups, and causes orientation polarization such that heat is generated. The absorption of infrared (IR) radiation causes the vibrations of atoms, but no bond breakages, while visible and ultraviolet (UV) light interacts with the shell electrons of the atoms, giving rise to the generation of electronically excited states that can undergo chemical reactions with surrounding molecules and thus causing chemical alterations. Also at frequencies higher than about 1015 Hz, photons interact with the shell electrons of the atoms. As the photon energies now exceed the shell electrons' ionization energy the latter can be expelled and, as a consequence, chemical bonds are broken, chemical alterations occur, and the physical properties of polymers are altered. When the expelled electrons possess relatively high kinetic energies they can dig their own tracks and ionize and electronically excite other molecules in the process. In the context of absorption, it is notable that electromagnetic radiation is an important tool for synthesizing polymers via the polymerization of small molecules.

Electromagnetic radiation passing through matter can also be attenuated by scattering. The electric field of the radiation is thought to cause vigorous vibrations of the shell electrons of atoms, thus forming oscillating dipoles which are themselves the source of electromagnetic waves that are emitted over the whole space. The wavelengths of the emitted waves are equal to those of the incident waves. Scattering can also be seen as elastic collision of photons with shell electrons. Recently, the scattering of both X-rays and of visible light has attracted analytical importance for synthetic and biopolymers.

This book describes in detail how the different types of electromagnetic radiation are attenuated by polymers, and highlights many of the applications related to the interaction of electromagnetic radiation with polymers. Typical applications refer to microwave heating used for the vulcanization of rubber and for recycling polymer waste. Radiofrequency or microwave-based plasma techniques are employed for the industrial processing of polymeric materials. Non-destructive microwave testing is an important tool for inspecting dielectric polymer coatings in a non-contact fashion. The IR region is related to important analytical applications, and IR analysis is nowadays an important tool for identifying and characterizing commercial polymers and for elucidating the spatial structure of proteins. Terahertz (1012 Hz) transmission spectroscopy has the potential for determining the content of additives in a polymer system in a contactless and non-destructive manner. Moreover, terahertz spectroscopy can also be used to identify nucleotide sequences in genes in a label-free manner and to measure the rate of folding and unfolding of proteins. Processes based on the interaction of visible and UV light with polymers have become important for a variety of applications. For example, polymers are used as photoresists in the production of computer chips, as core materials for optical wave guides, and as photoswitches and optical memories. Polymers are also employed in photocopying machines and in solar cells for the generation of energy. Moreover, VIS-UV light serves as a tool for the synthesis of polymers; that is, to initiate the polymerization of small molecules, a process that is applied not only in technical processes that involve the curing of coatings and adhesives but also in dentistry to cure tooth inlays.

Technical processes that employ ionizing radiation are widely applied in the polymer field, and include the production of crosslinked wire insulation and of heat-shrink food wrappings and tubings for electrical connections, the vulcanization of rubber tires and rubber lattices, and the curing of coatings and inks. Moreover, various X-ray methods can also be applied for the characterization and analysis of polymers, especially of the polymer surfaces. Both, X-ray imaging and X-ray microscopy allow the derivation of quantitative composition maps of polymer surfaces. Notable in this context are also near-edge X-ray absorption fine structure spectroscopy (NEXAFS), extended X-ray absorption fine structure spectroscopy (EXAFS) and X-ray photoelectron spectroscopy (XPS).

The phenomenon of X-ray scattering forms the basis of techniques that serve to characterize semicrystalline synthetic polymers, to elucidate the chemical structure of biopolymers (e.g., certain proteins), and to determine size, shape and state of aggregation of macromolecules in solution. X-ray scattering is also an important tool for characterizing biopolymers such as proteins and nucleic acids in the native state.

Within this book, the chemical and physical processes involving the interaction of electromagnetic radiation with polymers are addressed in two parts, with Part I being devoted to non-ionizing radiation and Part II to ionizing radiation. In Part I, the interaction of sub-terahertz radiation, infrared radiation and VIS-UV light with polymers, and their practical applications are detailed in separate chapters. In contrast, the three chapters of Part II relate to the absorption of high-energy photons (Chapter 4), to high-energy radiation-induced chemical reactions and related applications (Chapter 5), and to the application of high-energy radiation in polymer physics (Chapter 6).

It is customary to deal with the interaction of electromagnetic radiation with polymers separately with respect to the various frequency ranges, and a typical example of this can be found in the present author's book Polymers and Light, published in 2007 by Wiley-VCH. However, it was the author's notion to provide an overview in a single book covering the very broad frequency range referred to above and, of necessity, a concise working mode had to be applied and concentration on essentials was afforded.

Part I

Non-Ionizing Radiation