Textiles, additives Flame retardants

Used industrially as a lubricant additive, flame retardant in textiles, to manufacture adhesives, and as a chemical intermediate. 

Used industrially as a chemical intermediate in the manufacture of pesticides and phos-phosilicate glass. Used as a gasoline additive, catalyst, and as a fireproofing agent in the production of textiles and flame-retardant polymers for polyurethane foams. 

PBBs and PBDEs belong to a group of brominated organic compounds which are used as flame retardants. Flame retardants are valued for their ability to inhibit combustion in plastics, textiles, electric, and other materials. There are different groups of flame retardants inorganic and organic chemicals. Usually they are divided into reactive and additive flame retardants. 

Headliners are particularly complex textile-based composites because not only do they incorporate acoustic insulative materials but they also incorporate components such as internal mirrors, interior lighting, and associated wiring - a particular fire hazard. A typical structure described by Fung and Hardcastle shows that up to seven or more component layers may be present in a modem headliner, as outlined in Table 11.11 such a structure is truly a technical textile. The whole composite must be thermoformable with individual layers bound together using adhesive films or powders. Careful selection of each component is essential if it is to pass FMVSS 302 without the need for additional flame retardant treatment. 

In many cases, even normal textiles must be made fireproof. In principle, this objective can be achieved in three ways copolymerization with small amounts of a flame-retarding comonomer, addition of flame-retarding low-molar-mass substances to the spinning solution, or post-treatment of the textiles with flame retardants. The last method is indeed very flexible and economic but does not always yield completely technologically satisfactory results. Consequently, it is only used for the natural fibers wool and cotton. 

Within the area of textiles, coatings and back-coatings are applied either to confer a level of flame retardancy alone or as an additional flame retardant property to another coating function such as water repellenqr, for example. 

TBBPA has found use as a reactive flame retardant in the production of epoxy and polycarbonate resins added to circuit boards used in computers and in many other devices. In about 10% of cases TBBPA is used as an additive flame retardant, especially in the production of acrylonitrile-butadiene-styrene polymers, polystyrene, papers, textiles, televisions, office equipment and others. 

HBCD has been used as an additive flame retardant for more than 20 years. Its main use is in the construction industry, where it is used in polystyrene foams, which are a part of the thermal isolations, and even small concentrations provide sufficient protection against burning. The second major application of HBCD is in the upholstery and textile industries. Products in which the HBCD occurs, for example, include upholstered furniture, various textiles, car seats and upholstery, insulation in trucks and caravans as well as many types of building materials. Unlike other flame retardants, HBCD is not used in electronic circuits. 

In this case, the components are mixed, the pH adjusted to about 6.0 with sodium hydroxide, and the solution appHed to the textile via a pad-dry-cure treatment. The combination of urea and formaldehyde given off from the THPC further strengthens the polymer and causes a limited amount of cross-linking to the fabric. The Na2HP04 not only acts as a catalyst, but also as an additional buffer for the system. Other weak bases also have been found to be effective. The presence of urea in any flame-retardant finish tends to reduce the amount of formaldehyde released during finishing. 

Textile Flame Retardants. The first known commercial appHcation for phosphine derivatives was as a durable textile flame retardant for cotton and cotton—polyester blends. The compounds are tetrakis(hydroxymethyl)phosphonium salts (10) which are prepared by the acid-cataly2ed addition of phosphine to formaldehyde. The reaction proceeds ia two stages. Initially, the iatermediate tris(hydroxymethyl)phosphine [2767-80-8] is formed. 

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 ... 

Uses. As a flame retardant, a preignition additive for gasoline, an antifoam agent, a plasticizer and stabilizer, a textile conditioner, and an antistatic agent used experimentally to mimic the physical and spectroscopic (but not biological) properties of anticholinesterase agents... 

Back-coating is the major area where bromine-based flame-retardant compounds are used for textiles. This technique is applied primarily in applications such as upholstery and wall coverings. The system would comprise an FR additive with a latex binder, the latter often based on acrylic or ethylene vinylacetate. Use of vinylidene chloride-modified acrylics reduce the amount of tire-retardant additive required. 

A mixture of ammonium chloride and borax was one of the treatments of cellulosic fabrics reported by Gay-Lussac in 1821. Due to its low dehydration temperature and water solubility, sodium borates are only used as flame retardants in cellulose insulation (ground-up newspaper— see Sections 9.2.1.2 and 9.2.2.1), wood timber, textiles, urethane foam, and coatings. For example, a mixture of urethane (100 parts), borax (100 phr), and perlite (30phr) was claimed to provide flame-retardant urethane foam.8 Borax in conjunction with boric oxide, silica, ammonium chloride, and APB as ceramizing additives and volume builders, are claimed in a fire-protection coating based on polybutadiene and silicone microemulsion.9 Using a modified DIN 4102 test, the chipboard with the coating showed a loss of mass less than 1% and there was no pyrolysis of the wood sample. 

Considerable interest has been directed to the preparation of cellulose phosphates because of their flame retarding properties and potential use in textiles. Phosphorylation can be accomplished in several ways, e.g., by heating cellulose at high temperatures with molten urea and phosphoric acid. Other phosphor-containing esters of cellulose include phosphites, phosphinates, and phosphonites. In addition, boric acid esters have been prepared. 

Can cause testicular atrophy and sterility. Once used as a flame retardant additive to synthetic textiles and plastics, particularly in children s sleepwear. Use discontinued because it can be absorbed by human skin, or chewed or sucked off sleepwear by infants. May be flammable when exposed to heat or flame. When heated to decomposition it emits very toxic fumes of Br" and POx. 

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