Fire and Polymers V - ACS Publications - American Chemical Society

Chapter 1

Fire Retardancy in 2009 1

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Downloaded by 80.82.77.83 on January 2, 2018 | http://pubs.acs.org Publication Date: April 27, 2009 | doi: 10.1021/bk-2009-1013.ch001

Gordon L . Nelson , Alexander B. Morgan , and Charles A. Wilkie

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1Florida Institute of Technology, 150 West University Boulevard, Melbourne, FL 32901-6975 University of Dayton Research Institute, 300 College Park, Dayton, OH 45469-0160 3Department of Chemistry, Marquette University, PO Box 1881, Milwaukee, WI 53201-1881 2

Fire continues to be a worldwide problem. It claims thousands of lives and causes tens of billions of dollars in loss of property every year. In this 5th volume of Fire and Polymers, current fire-related problems are discussed and solutions delineated. This peer-reviewed volume is designed to be representative of the state-of-the-art and places current work in perspective.

Introduction In the United States every 20 seconds a fire department responds to a fire somewhere in the country. A fire occurs in a structure at the rate of one every 59 seconds. A residential fire occurs every 76 seconds. A fire occurs in a vehicle every 122 seconds. There is a fire in an outside property every 41 seconds. The result is 1.6 million fires per year (2007) attended by public fire departments. In 2007 those fires accounted for $14.6 billion in property damage and 3430 civilian fire deaths (one every 153 minutes) and 17,675 injuries (one every 30 minutes). Some 105 fire fighters died in the line of duty in 2003. Fires have declined over the period 1977 to 2007, most notably structural fires, from 1,098,000 to 530,500. Civilian fire deaths in the home (80% of all fire © 2009 American Chemical Society

Wilkie et al.; Fire and Polymers V ACS Symposium Series; American Chemical Society: Washington, DC, 2009.

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declined from 6,015 in 1978 to 2,865 in 2007. While those declines are progress, recent years have been static, and the United States still maintains one of the highest rates of fire in the world. Just as the U.S. has a high fire rate, the fire death rate in the US varies by state, from 30/million population in Arkansas to 3/million in Utah. Fire deaths vary by size of community, from 10/million in communities above 25,000 people to 26/million for communities under 2500 people. Importantly, 70% of fire deaths in the U.S. occur in homes without working smoke alarms, this despite years of effort to achieve a high penetration The higher rate of fire in the United States versus most industrialized countries is probably a product of five factors: (1) the U.S. commits fewer resources to fire prevention activities; (2) there is a greater tolerance in the U.S. for "accidental" fires (no one is at fault); (3) Americans practice riskier and more careless behavior than people in other countries (example, the use of space heaters); (4) homes in the U.S. are not built with the same degree of fire resistance and compartmentation as in some countries; and (5) most importantly, people in the U.S. have more contents or "stuff' than those in other countries (i.e., higher fire load) as well as a higher number of ignition sources (higher use of energy). Polymers form a major part of the built environment. Fire safety depends upon those materials. Polymers are "enabling technology" for almost all of modern society as we know it today. Advances in numerous technologies depend on appropriate advances in polymers for success. While polymers are both natural and synthetic, this book focuses entirely on the fire safety aspects of synthetic polymers. Production of synthetic plastic resins totaled over 169 million metric tons worldwide in 2003 (4). The U.S. constitutes about one quarter of worldwide plastic consumption, the European Union only slightly less and Japan about 9%. In Table I, one finds 2007 plastic production figures by resin for North America (5). In Table II, one finds 2007 plastics use data by resin for North America (5). A l l organic polymers are combustible. They decompose when exposed to heat, their decomposition products burn, smoke is generated, and the products of combustion are highly toxic. The prime toxic product is C O in concert with C 0 . While at times the heat from a fire can kill far sooner than toxic combustion gases, the preponderance of fire victims die in post-flashover fires in a room outside the room of origin, from toxic gases in smoke. That toxicity is made more complex by the pervasive presence of alcohol on the part of fire victims, 52% of young adult fire victims and 74% of middle-aged fire victims have significant blood alcohol. Alcohol got them into the incident. Fire kills young children, the old and infirm, and the drunk, not healthy unimpared adults (6). Fire is not a single material property and is regulated by many material parameters. Fire behavior from a material combines ease of thermal 2


3 Table I. North American Plastics Production* - 1999 and 2007 (millions of pounds, dry weight basis) Resin Epoxy Urea and melamine Phenolics (gross wt) Total Thermosets LDPE LLDPE HDPE ppc c

c

C

C


C

c

m

ABS Other Styrenics PS Nylon PVC Thermoplastic Polyester Total Thermoplastics All Other Resins Grand Total cm

cm

C

1999 Production 657 2,985 4,388 8,030 7,700 8,107 13,864 15,493 1,455 1,767 6,471 1,349 14,912 4,846 75,964 13,467 97,461 c

2007 Production 642 3,471 4,838 8,951 7,927 13,584 18,222 19,445 1,270 1,726 6,015 1,295 14,606 8,745 92,835 14,007 115,793 m

NOTES: * US, Canada and Mexico as noted, Canada Included, Mexico Included

Table II. Resins Sales By Major Markets (millions of pounds) Major Market Transportation Packaging Building & Construction Electrical/Electronic Furniture & Furnishings Consumer & Institutional Industrial/Machinery Adhesives/Inks/Coatings All Others Exports Total Selected Plastics*

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2007 3,312 26,527 14,289 1,980 3,091 17,193 943 1,069 1,604 12,346 82,354

% 4.0 32.2 17.4 2.4 3.8 20.9 1.1 1.3 1.9 15.0 100.0

NOTE: 'Data for ABS, SAN, Other Styrene-Based Polymers, and Engineering Resins are not included.



4 decomposition, ease of ignition, flame spread, heat release, ease of extinction, smoke generation, toxic potency and other properties. Since fire risk has been known for a very long time, the field of fire safety engineering looks at specific scenarios where fires can occur, and works with government through codes and standards to minimize fire events and subsequent losses should the fire blaze out of control. These codes and standards use specific tests covering the properties of material flammability described above. The results of these tests are combined with engineering assessments for materials and systems as deemed appropriate for a particular application. Thus, for example, it is appropriate in small appliances to only worry about ignitability by a Bunsen burner flame or a needle flame, since in the application, from an internal point of view, that is the size of a fire source (from an electrical short) possible in real appliance failures. While there are some polymers that are very difficult to ignite or consume with flame, most other polymers require flame retardant additives to pass the regulatory tests required for safe use and sale of polymeric material containing goods. The total market for flame retardants in the United States, Europe, and Asia in 2004 amounted to about 1.5 million metric tons and was valued at $2.82.9 billion. The market is expected to grow at an average 3% annual rate on a volume basis (7,8). Figure 1 shows the consumption of flame retardants by region (2004). Different flame retardants are prominent in different regions. Figure 2 shows relative consumption of different flame retardants by region (7).

Figure 1. Consumption of Flame Retardants by Region - 2004



Figure 2. Relative Consumption of Flame Retardants by Region - 2004


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With this background in place, one can see that research on fire safety of polymers has an important role to play in modern society. This volume is about the latest research at the intersection of the fields of fire and polymers with a strong focus on material chemistry. Within this volume, work is focused on improving the fire performance of polymers through a detailed understanding of polymer degradation chemistry. New and refined analytical techniques facilitate that analysis. Creative chemists continue to develop new approaches and new, more thermally stable flame retardant and polymeric structures. Mathematical fire models continue to become more sophisticated and the fire tests themselves are becoming better understood. There are many diverse approaches to enhancing the fire stability of polymers. In the past, the most common approach involved the use of additives to the polymer via compounding approaches. Twenty years and more ago halogenated fire retardants (with antimony oxide) were the additives of choice to enhance the fire retardancy of many polymers. Over the past 10 years there has been a strong emphasis on non-halogenated fire retardants, and nano-scale additives in particular. As one looks at previous Fire and Polymers volumes, topics have clearly changed over the years. In 1990 fire toxicity was the first section with six papers. In 1995 there again was a section on fire toxicity with seven chapters. In 2001 there was but one paper, in 2006, 3 and in this volume, only one. In 1990 there was a section on cellulosics, in 2001 only 1 chapter, and in the 2006 and this volume, none. In the 1995 volume there were twelve chapters on tests and regulations, in 2001, 2, and in this volume, none. In the 2006 volume, half of the papers were on nanocomposites and only two papers had a focus on halogen materials specifically. Once again, in this volume, the majority of the papers are concerned with nanocomposites and their affect on flammability, but there are nine papers dealing with either conventional or novel fire retardant systems. This peer-reviewed volume is designed to represent the state of the art in new approaches to flame retardant materials, and new understanding of polymer flammability phenomena (9-/2).

References 1. 2. 3. 4.

Karter, Jr., M . J. Fire Loss in the United States During 2007; National Fire Protection Association: Quincy, M A , August, 2008. Fire Loss; National Fire Protection Association; http://www.nfpa.org U S F A State Fire Statistics; http://www.usfa.fema.gov/statistics/state/ Plastics in Europe, A n analysis of plastics consumption and recovery in Europe; Association of Plastics Manufacturers; Summer 2004.


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A P C Year End Statistics for 2007; http://www.americanplasticscouncil.org 6. Toxicological Issues in Fires: Carbon Monoxide or Additives?, G.L. Nelson, Proceedings: Additives 2001: Plastics for the New Millennium, Executive Conference Management (Hilton Head, SC, March 18-21, 2001). 7. Fink, U.; Hajduk, F.; Ishikawa, Y . ; Flame Retardants, http://www.sriconsulting.com/SCUP/Public/Reports/FLAME000 8. U.S. Demands for Flame Retardants to Grow; October, 2007; http://www.pcimag.com/copyright/BNP_GUID_9-5-2006_A_1000000... 9. Fire and Polymers, Hazards Identification and Prevention; Nelson, G.L.; Ed.; American Chemical Society; Washington, D C , 1990. 10. Fire and Polymers II, Materials and Tests for Hazard Prevention; Nelson, G . L.; Ed.; American Chemical Society; Washington, DC, 1995. 11. Fire and Polymers, Materials and Solutions for Hazard Prevention; Nelson, G.L. and Wilkie, C.A.; Eds.; Washington, DC, 2001. 12. Fire and Polymers IV, Materials & Concepts for Hazard Prevention; Wilkie, C.A.; and Nelson, G.L. ; Eds.; Washington, DC, 2006.


Fire and Polymers V - ACS Publications - American Chemical Society

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