Flame-retardant research

Some of the preeminent fire-safety and flame-retardant research organizations worldwide are listed in the following text. The list is by no means comprehensive, and focuses on the organizations that are known to publish often in the fields of flame-retardant research or fire-safety engineering. This list includes links to the organizations to learn more about the range of services and research they offer. 

Metal-containing compounds appear to be the most promising flame retardants. Research in this direction is still in the nascent state but the very first results demonstrate the high effectiveness of this type of flame retardants and iheir ability to control the combustion process on a catalytic level. 

Foaming of PAI will result in heat-resistant foams. There are such foams made from other types of polymers. Advantages and drawbacks of typical high heat-resistant foams are compared in Table 14.2. PI resin foams are regarded as one of the most applicable materials by virtue of their excellent heat stability and flame retardancy. Research has been targeted to improve the physical properties and to simplify the process of preparation. On the other hand, PAI resins exhibit a better heat resistance than poly(ether imide) resins. In addition, they can be more easily processed in the melt. 

Simon, J., Androsits, B., Szalay, B. and Lantos, S. The application of derivatograph in flame retardation research, determination of ignition temperature. Hungarian Scientific Instruments, No. 48, 1 (1980)... 

Unique to flame retardant and fire-safe materials research is that fire safety codes and regulations drive the field more than any other phenomena. In addition, there are new trends, codes, and regulations which appear on the surface to have no relation to the flammability performance of materials, but are currently driving the field of flame retardant research. These codes, typically enviromnental in nature, can adversely affect fire safety for polymeric materials and, in turn, limit the existing flame retardant solutions that could yield acceptable fire safety. 

The Brominated Flame Retardants Industry Panel (BFRIP) was formed ia 1985 within the Flame Retardant Chemicals Association (FRCA) to address such concerns about the use of decabromodiphenyl oxide. Siace 1990 the BFRIP has operated as a Chemical Self-Funded Technical Advocacy and Research (CHEMSTAR) panel within the Chemical Manufacturers Association (CMA) (64). As of 1993, members of BFRIP are Ak2o, Amerihaas (Dead Sea Bromine Group), Ethyl Corp., and Great Lakes Chemical. Siace its formation, BFRIP has presented updates to iadustry on a regular basis (65,66), and has pubhshed a summary of the available toxicity information on four of the largest volume brominated flame retardants (67,68) tetrabromo bisphenol A, pentabromodiphenyl oxide, octabromodiphenyl oxide, and decabromodiphenyl oxide. This information supplements that summarized ia Table 11. 

Research sponsored by BFRIP regarding the use of brominated flame retardants shows that there is no evidence that the use of decabromodiphenyl oxide leads to any unusual risk. In addition, a study by the National Bureau of Standards (now National Institute of Science and Technology) showed that the use of flame retardants significantly decreased the ha2ards associated with burning of common materials under reaUstic fire conditions (73). Work ia Japan confirms this finding (74). 

Product Toxicology. The stmcture—toxicity relationships of organophosphoms compounds have been extensively researched and are relatively well understood (138—140). The phosphoms-based flame retardants as a class exhibit only moderate-to-low toxicity. NIOSH or EPA compilations and manufacturers safety data sheets show the following LD q values for rats, for representative commercial phosphoms flame retardants ... 

Trends in the research and development of phosphoms flame retardants have been in the direction of less volatile, less toxic, more stable compounds, and where feasible, in the direction of built-in phosphoms stmctures. At the same time, there have been an increasing number of regulatory delays in new compounds, and the existent materials are finding increased exploitation in the form of mixtures. Some interest is also noted in encapsulation. 

APO. Research on ethylenimine [151 -56-4] led to the development of tris(azitidinyl) phosphine oxide [545-55-1] (APO) as a flame retardant for... 

R. J. Harper, Jr., and M. E. Demorais, "Durable-Press Flame Retardant Fabrics Based on the LHPOH—NH Precondinsate System," Hational Technical Conference, AATCC, Montreal, Canada, Oct 6—9, 1985, American Association of Textile Chemists and Colorists, Research Triangle Park,... 

High purity hexafluorozirconic acid and its salts are produced by Advance Research Chemicals of the United States, and Akita and Moritta of Japan. The technical-grade green-colored material is suppHed by Cabot Corp. of the United States. In 1993, the U.S. market for fluorozirconic acid was about 250,000 kg/yr the world market was less than 500,000 kg/yr. A principal part of this production is consumed by the wool, garment, and upholstery industries. The 1993 price varied between 2.4 to 6.6/kg depending on the quaUty and quantity required. Potassium fluorozirconate [16923-95-8], K ZrF, is commercially important the world market is about 750,000 kg/yr. The most important appHcation is as a fire-retardant material in the wool (qv) industry, for the manufacture of garments, upholstery for aeroplane industry, and children s clothes (see Flame retardants). The 1993 unit price was between 5.0 and 6.6/kg. 

Polycarbonates are prepared commercially by two processes Schotten-Baumaim reaction of phosgene (qv) and an aromatic diol in an amine-cataly2ed interfacial condensation reaction or via base-cataly2ed transesterification of a bisphenol with a monomeric carbonate. Important products are also based on polycarbonate in blends with other materials, copolymers, branched resins, flame-retardant compositions, foams (qv), and other materials (see Flame retardants). Polycarbonate is produced globally by several companies. Total manufacture is over 1 million tons aimuaHy. Polycarbonate is also the object of academic research studies, owing to its widespread utiUty and unusual properties. Interest in polycarbonates has steadily increased since 1984. Over 4500 pubflcations and over 9000 patents have appeared on polycarbonate. Japan has issued 5654 polycarbonate patents since 1984 Europe, 1348 United States, 777 Germany, 623 France, 30 and other countries, 231. 

Flame Retardants. The amount of research expended to develop flame-retardant (FR) finishes for cotton and other fabrics has been extremely large in comparison to the total amount of fabrics finished to be flame retardant. The extent of this work can be seen in various reviews (146—148). In the early 1960s, a substantial market for FR children s sleepwear appeared to be developing, and substantial production of fabric occurred. In the case of cotton, the finish was based on tetrakis(hydroxymethyl)phosphonium chloride (THPC) or the corresponding sulfate (THPS). This chemical was partly neutralized to THPOH, padded on fabric, dried under controlled conditions, and ammoniated. The finish was subsequently oxidized, yielding a product that passed the test for FR performance. This process is widely preferred to the THPOH—NH process. 

Another fire-related problem that has seen some research effort is that of smolder resistance of upholstery and bedding fabrics. Finishing techniques have been developed to make cotton smolder-resistant (152—156), but the use of synthetic barrier fabrics appears to provide a degree of protection. Work also has provided a means of producing cotton fabrics that have both smooth-dry and flame-retardant performance (150,151). In this case, the appHcation of FR treatment should be performed first, and DP treatment should be modified to accommodate the presence of the FR polymer on the fabric. 

Laidlaw, R. A. and Pinion, L. C., Metal Plate Fasteners in Trussed Rafters Treated with Preservatives of Flame Retardants-Corrosion Risks, IS 11/77, Building Research Establishment (1977)... 

Flame Retardant Treatments for Timber, Wood Information 2/3, Sheet 3, Timber Research and Development Association (1988)... 

ICI Acrylics believes that greater cooperation between companies and a revised approach to life cycle analysis are the keys to the industry s future environmental sustainability. The company has invested over 2m pounds sterling in an on-going monomer recovery project, which encompasses a joint research programme with Mitsubishi Rayon. The project focuses on increasing the efficiency of acrylic depolymerisation and overcoming technical issues such as its use in recycling flame retardant acrylics. ICI ACRYLICS... 

Eastern Research Group and Syracuse Research Corporation (2005) Furniture Flame Retardancy Partnership Environmental Profiles of Chemical Flame-Retardant Additives for Low-Density Polyurethane Foam. United States Environmental Protection Agency, EPA 742-R-05-002A. 

In order to accomplish with the aforementioned aim, during the first year of project, an extensive research on the different chemical additives used in six industrial sectors was conducted plastics, textiles, electronics, lubricants, leather, and paper. A list of selected chemical additives was identified for each sector and used as a study basis for the rest of the project. This is the case of the decabromo-diphenyl ether (BDE) used in electronics as a flame retardant or the triclosan used in the textile as a biocide. The results of this investigation were presented in the first volume of this book (Global Risk-Based Management of Chemical Additives I Production, Usage and Environmental Occurrence). This volume also included a section of case studies related to the selected additives in different countries (i.e., Denmark, Vietnam, Brazil, India). The main outcomes of the first part of the project are summarized below ... 

Studies at the International Tin Research Institute showed that 2.5% zinc stannate strongly enhanced the flame retardant action of ATH in ethylene-acrylic rubber, and enhanced the char yield (34) (Fig. 5). 

The antimony oxide/organohalogen synergism in flame retardant additives has been the subject of considerable research and discussion over the past twenty-five years (1-17). In addition to antimony oxide, a variety of bismuth compounds and molybdenum oxide have been the subject of similar studies (18-20). Despite this intensive investigation, relatively little has been conclusively established about the solid state chemical mechanisms of the metal component volatilization, except in those cases where the organohalogen component is capable of undergoing extensive intramolecular dehydrohalogenation. 

In summary, new brominated flame retardants have essentially met the challenge for thermoplastics that do not meet current requirements (e.g. a V-0 rating) without additives. More stringent flammability requirements for advanced materials and applications, coupled with improved test methodology (e.g. lOa-b) may shift the focus of research to other approaches. 

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