Flame retardants in rubber

Some inorganic fillers are used as flame retardants in rubber base formulations. Flame retardants act in two ways (1) limiting or reducing access of oxygen to the combustion zone (2) reacting with free radicals (especially HO ), thus acting as terminator for combustion-propagation reaction. The additives most widely used as flame retardants for polymers are antimony oxides and alumina trihydrate. 

Shen, K.K. and Schultz, D. 2001. Flame retardants. In Rubber Technology—Compounding and Testing for Performance, Hanser, Munich, Germany, p. 248. 

In 1994, 70 tons of SCCPs were used in Switzerland, and it is estimated that uses have reduced by 80%. The most widespread use of SCCPs in Switzerland was in joint sealants. In Germany, the most important uses (74% of the total) of SCCPs were banned by the EU directive 2002/45/EC. SCCPs have been used as a polychlorinated biphenyl (PCB) substitute in gaskets (e.g. splices, in buildings), and this may be a source when buildings are renovated. Brazil indicates that 300 tons per year is used in Brazil for the purposes of flame retardant in rubber, car carpet and accessories. Use of SCCPs in Austraha decreased by 80% between 1998/2000 and 2002 to approximately 25 tons per year of SCCPs in the metalworking industry [16]. In the Republic of Korea and in 2006, SCCPs were mainly used in lubricant and additive agents. The release pattern and quantitative data are not available. Also, the Republic of Mauritius reported that it does use SCCPs [17]. 

Flame retardant in rubber. Antimony trioxide, aluminum trioxide, acrylic polymers and... 

Used as plasticiser and flame retardant in rubber products such as gaskets, sealants and glues, which have been used, e.g., in construction sector and car industry... 

Uses Lubricant resin extender, plasticizer improving water, chem., oil, and gas resist, in traffic paints, protective coatings plasticizer, flame retardant in rubbers, vinyls, fabric coatings, plastisols, rug backings, thermosetting encapsulants EP agent in metalworking fluids Features Blend of Paroil 1057 and 1061... 

A manufacturer considering using a thermoplastic elastomer would probably first consider one of the thermoplastic polyolefin rubbers or TPOs, since these tend to have the lowest raw polymer price. These are mainly based on blends of polypropylene and an ethylene-propylene rubber (either EPM or EPDM) although some of the polypropylene may be replaeed by polyethylene. A wide range of blends are possible which may also contain some filler, oil and flame retardant in addition to the polymers. The blends are usually subject to dynamic vulcanisation as described in Section 11.9.1. 

Antimonious acid H3Sb03 and its salts are less well characterized but a few meta-antimonites and polyantimonites are known, e.g. NaSb02, NaSb305.H20 and Na2Sb407. The oxide itself finds extensive use as a flame retardant in fabrics, paper, paints, plastics, epoxy resins, adhesives and rubbers. The scale of industrial use can be gauged from the US statistics which indicate an annual consumption of Sb203 of some 10000 tonnes in that country. 

TG-MS is an ideal technique for identifying residual volatiles in polymers. The detection of residual volatiles (and of other impurities) can often yield clues as to manufacturing processes. In many cases, such as in the determination of highly volatile materials, of residual solvents or plasticisers, use of TG-MS is requested. Specifically, there are reports on the entrapment of curing volatiles in bismaleimide laminates [145] and elastomers [48], on the detection of a curing agent (dicumylperoxide) in EPDM rubbers and of bromine flame retardants in electronic waste [50], of plasticisers such as bambuterol hydrochloride [142] or TPP and diethylterephthalate in cellulose acetate [143], on solvent extraction and formaldehyde loss in phenolic resins [164], and on the evolution of toxic compounds from PVC and polyurethane foams [146]. 

Deca-BDE is the most common of all the commercial BDE flame retardants. The commercial Deca is generally 95% or more of the BDE-209 congener. It is primarily used as a flame retardant in the hard, dense plastics of consumer electronics products and in the latex back coating of flame retardant upholstery textiles. It can be found in many different polymers including polycarbonates, polyesters, polyolefins, ABS, Polyamides, PVC and rubbers. 

Use As fillers in rubber, paper, plastics, adhesives, polishes, inks, paints, cosmetics, and as a flame retarder in plastics. 

Composite plastics and rubbers are being used preferably in other transportation applications (wagons of metros, trains, airplane interiors), where flammability as well as VOC are important. In general, PF or epoxy composites are used, and certainly it is compulsory to use carefully selected flame retarders in such mass-transport systems. In such applications, it should always be remembered that, not only flames are important in these applications, hut, the smoke production is very important and critical too. 

Uses Flame retardant in adhesives (mastic, pressure sensitive), coatings (aluminum, can drum, emulsion, fabric, industrial, marine, traffic, wire cable), rubber (cements, mechanical and molded goods), textiles, concrete-curing compds., caulking compds. plasticizer for resins EP agent in metalworking fluids Features Stable low vise. exc. sol. 

Uses Pigment in white and opaque glass, plastics, rubber, dyeing, paints, linoleum, leather, dental rubber fluorescent pigment in paints and plastics ingred. of lithopone fungicide anhydrous in x-ray screens, TV screens flotation depressant for sphalerite ores flame retardant in plastics, elastomers, textiles, paper depilatory agent in cosmetics in food-pkg. adhesives filler in food-contact rubber articles for repeated use colorant in food-contact polymers in lubricants for incidental food-contact use... 

In addition to the polymer matrix itself, information may be obtained about additives, such as tackifying resins in rubber, flame retardants in polystyrenes, " plasticizers, antioxidants, etc. The study of polymers using pyrolysis in general has been broadened by techniques permitting hydrolysis and methylation, typically by the addition of tetramethyl ammoifium hydroxide to the sample, as described in a review by Challinor." ... 

Inorganic phosphates. Inorganic phosphates consist of ammonium polyphosphate and red phosphorus. The ammonium polyphosphate product is primarily used in intumescent coatings and rubber as well as plastics. Red phosphorus is used as a flame retardant in coatings and nylon. 

W. Yuan, H. Chen, R. Chang, L. Li, Synthesis and characterization of NaA zeolite particle as intumescent flame retardant in chloroprene rubber system, Particuology, ISSN 1674-2001 9 (3) (June 2011) 248-252. http //dx.doi.oig/10.1016/j.partic.2010.05.016. 

Uses intermediate in the manufacture of polymers, epoxy resins, acrylic resins, polycarbonates, fungicides, antioxidants, dyes, phenoxy, polysulfone and certain polyester resins, flame retardants and rubber chemicals component in semisynthetic waxes polycarbonate resins (60%), epoxy resins, (30%), polysulfone, polyetherimide and polyacrylate resins (10%) flame retardants (mainly tetrabromobisphenol-A), unsaturated polyester... 

Flame retardancy in various polymers has been discussed both in general terms [77] and for particular types of polymers including polyvinyl chloride (PVC) [78], polystyrene foam [79], unsaturated polyester resins [80, 81], polyisocyanurate-polyurethane (PU) water-blown foams [82], ethylene-vinyl acetate copolymers [83], and plastic and rubber cables [84]. 

Used as a plasticizer and flame retardant in the production of PVC, PS, PC, butadiene rubber, cellulose acetate, and aceto-butyrate. 

Many times rubber compounds require a piasticizer. However, most plasticizers or processing oils hurt flame retardancy because they provide a fuel source to a potential fire if there is combustion. If a plasticizer must be used, the correct type of triaryl phosphate should function as both a plasticizer and a flame retardant in both the gas and condensed phases. 

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