Polymer nanocomposites flammability research

Morgan, A. B. and Wilkie, C. A. Practical issues and future trends of polymer nanocomposite flammability research, in Flame Retardant Polymer Nanocomposites, Morgan, A. B. and Wilkie, C. A. (Eds.) John Wiley Sons Hoboken, NJ, 2007, p. 421. 

PRACTICAL ISSUES AND FUTURE TRENDS IN POLYMER NANOCOMPOSITE FLAMMABILITY RESEARCH... 

The current state of polymer nanocomposite flammability research should by now be obvious, but some summary and review is needed to put this information into perspective. To date, we understand the following to be fundamentally important to polymer nanocomposite flammability ... 

Gilman JW, Bourbigot S, Shields JR et al. (2003) High throughput methods for polymer nanocomposites research extrusion, NMR characterization and flammability property screening. J Mat Sci 38 4451... 

Furthermore, another advantage of nanofillers is not only to reinforce the rubber matrix but also to impart a number of other properties such as barrier properties, flammability resistance, electrical/electronic and membrane properties, and polymer blend compatibility. In spite of tremendous research activities in the field of polymer nanocomposites during the last two decades, elastomeric nanocomposites... 

R 131 J.W. Gilman, S. Bourbigot, J.R. Shields, M. Nyden, T. Kashiwagi, R.D. Davis, D,L. Vander Hart, W. Demory, C.A. Wilkie, A.B. Morgan, J. Harris and R.E. Lyon, High Throughput Methods for Polymer Nanocomposites Research Extrusion, NMR Characterization and Flammability Property Screening , p. 1459... 

Recently, polymer nanocomposites based on clay minerals have attracted great interest from researchers, both in industry and in academia, because they often exhibit concurrent improvement in several properties of neat polymer. These improvements can include high moduli, increased strength and heat resistance, decreased gas permeability and flammability, and increased degradability of biodegradable polymers [7-12]. These materials have also been proven to be unique model systems to study the structure and dynamics of polymers in confined environments [20]. 

For more than a decade potential environmental problems associated with organo-bromine flame retardant systems have motivated the search for non-halogen-based approaches to reduce polymer flammability. Initially, research focused on development of new phosphorus-based flame retardants, and numerous publications and patents have been issued in this area. Similarly motivated research has also produced nonhalogen flame retardant approaches based on other elements, such as boron and sihcon. At the same time, work on the use of additives, or flllers, with nanometer-scale primary particle sizes, produced polymer nanocomposites. These materials exhibit enhancement in a variety of physical properties at one-tenth the loading required when micrometer-size additives are used. ... 

In this section we briefly review the initial development of clay nanocomposites and present initial work on their flammability properties. In the next section we review several studies aimed at determining the flame retardant mechanism of polymer-clay nanocomposites. This is not intended as an exhaustive review of all nanocomposite flanunability research instead, an attempt is made to present an objective view of the mechanism proposed for how clay nanocomposites reduce polymer flanunability, based on data from NIST and other research groups. 

This book focuses on polymer nanocomposites for flammability applications and includes supporting information important to this subject. The information is divided into sections for specific topic searching, and the book is divided into three parts to help those new to the fields of materials flammability research and polymer nanocomposites theory and fundamentals, specific flame retardant systems, and current applications and future work. 

For more than a decade, numerous research studies have been carried out on the flame-retardant properties conferred by nanoparticles and mainly by organo-modified layered silicates (OMLS). Earlier work at Cornell University and National Institute of Standards and Technology in the United States showed that nanocomposites containing OMLS reduced polymer flammability and enhanced the formation of carbonaceous residue (char).14 Owing to a strong increase in polymer viscosity, impairing processability, and also due to the breakdown of ultimate mechanical properties, the acceptable rate of incorporation for nanoparticles to improve flame retardancy is generally restricted to less than 10 wt %. 

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