Ebook: Plastics Additives

Modern polymer/additive deformulation is essentially carried out according to three different approaches, in increasing order of sophistication, namely analysis of analytes separated from the polymer (typically an extract), of analytes and polymer in solution, or directly in-polymer (solid state or melt). The current status of conventional, indirect, methods of deformulation of polymer/additive extracts and dissolutions has recently been described in a comprehensive fashion. However, there is an impelling need to tackle polymer/additive deformulations strategically in an ever-increasing order of sophistication in analytical ingenuity, from indirect to direct analysis procedures, from macro to micro, from slow to rapid, from close to remote, from lab to process. Established wet chemical routes for low-molecular-weight additives are frequently no option for analytical problems of considerable complexity (high-molecular-weight additives, grafting, incorporation in the polymer backbone, reactive systems, etc.) or in case of surface analysis, microanalysis and spatially resolved analysis. Profiling, process analysis, product safety, quality assurance and industrial troubleshooting all benefit from direct analysis modes.

In recent years, techniques for direct analysis of the non-polymer components have developed apace and it has become increasingly important for scientists, engineers and technicians to have a basic grounding in these methods. This treatise is concerned with the in situ characterisation of additives embedded in a broad variety of polymeric matrices and evaluates critically the extensive problem-solving experience and state-of-the-art in the polymer industry. Despite well-deserved attention and considerable efforts direct polymer/additive analysis (without separation) has not yet turned into a great many general and routinely workable concepts. Nevertheless, the future foresees a greater share for in-polymer analysis.

This book, containing an outline of the principles and characteristics of relevant instrumental techniques (without unnecessary detail), provides an in-depth overview of various aspects of direct additive analysis by focusing on a wide array of applications in R&D, production, quality control and technical service. The book describes the fundamental characteristics of the arsenal of techniques utilised industrially in direct relation to application in real-life polymer/additive analysis. Instrumental methods are categorised according to general deformulation principles with emphasis on promoting understanding and on effective problem solving. The chapters are replete with selected and more common applications illustrating why particular additives are analysed by a specific method. The value of the book stays in the applications.

In Plastics Additives: Advanced Industrial Analysis the author has attempted to bring together many recent developments in the field in order to provide the reader with valuable insight into current trends and thinking. For each individual technique more excellent textbooks are available, properly referenced, albeit with less focus on the analysis of additives in polymers.

As an alternative to wet chemical routes of analysis, this monograph deals mainly with the direct deformulation of solid polymer/additive compounds. In Chapter 1 in-polymer spectroscopic analysis of additives by means of UV/VIS, FTIR, near-IR, Raman, fluorescence spectroscopy, high-resolution solid-state NMR, ESR, Mössbauer and dielectric resonance spectroscopy is considered with a wide coverage of experimental data. Chapter 2 deals mainly with thermal extraction (as opposed to solvent extraction) of additives and volatiles from polymeric material by means of (hyphenated) thermal analysis, pyrolysis and thermal desorption techniques. Use and applications of various laser-based techniques (ablation, spectroscopy, desorption/ionisation and pyrolysis) to polymer/additive analysis are described in Chapter 3 and are critically evaluated. Chapter 4 gives particular emphasis to the determination of additives on polymeric surfaces. The classical methods of surface analysis (electron spectroscopy, surface mass spectrometry and ion scattering techniques) are applied to practical cases. A variety of options for (surface) microanalysis and spatially resolved analysis by means of microscopy, microspectroscopy, spectromicroscopy, and imaging techniques, as applied to polymer/additive materials, are discussed in Chapter 5. Quantitative analysis (Chapter 6) in an essential part of polymer/additive analysis, in particular in the industrial environment. For quantitation, the separation procedure can be the most important factor for success or failure of the analysis. While this analytical task is recognised to be considerably more difficult than the qualitative analysis of previous chapters, recent round-robins indicate the need for critical self-inspection of the polymer analytical community. In Chapter 7 the various tools for in-process analysis (UV/VIS, mid-IR, near-IR, Raman and low-resolution NMR) are applied to polymer melts. The current status of polymer/additive analytical methodology is described in Chapter 8 and optimisation procedures are outlined. The lack of certified reference materials hampers analytical method validation. A rational step-by-step method development and validation approach to polymer/additive analysis is described.

Each chapter of this monograph is essentially self-contained. The reader may consult any sub-chapter individually. To facilitate rapid scanning the text has been provided with eye-catchers. Each chapter concludes with up-to-date references to the primary literature (no patent literature) and a critical list of recommended general reading (books, reviews) for greater insight. The majority of references in the text are from recent publications (1980–2003 and beyond). The book ends with a glossary of symbols and an index compiled with respect to both instrumental methods and analytes. Although every effort has been made to keep the book up-to-date with the latest methodological developments this report represents only work in evolution and contains suggestions for future improvements. In J.R. Thorbecke's words “De tijd om alles te zeggen is nog niet gekomen”, or “Time is not yet ripe to tell everything”.

Geleen, December 2004