Flame-retarded thermoplast, formulations

The demands on a flame retardant and thermoplastics formulated with such agents are manifold. The flame retardant should provide a durable flame-retarding effect by the addition of only small quantities of the additive it should be as cheap as possible and the manner of incorporation should be easy it should be nontoxic and should not produce fire effluents with increased toxicity it should not decompose at the processing temperatures it should not volatilize and smell and the mechanical, optical, and physical properties of the thermoplastics should be affected as little as possible. It is understandable that these far-ranging demands cannot be satisfied by only one flame retardant and for all thermoplastics with their manifold applications. One is therefore forced to seek the optimum flame retarding formulation for each thermoplastic and the specific application. Examples of typical formulations of several flame-retarded thermoplastics are given in Appendix A8. 

Flame retardant intumescent formulations have been developed using charring polymers PA6, thermoplastic polyurethanes (TPUs), and hybrid clay-PA6 nanocomposites as carbonisation agents. The advantage of the eoncept is to obtain FR polymers with improved mechanical properties and to avoid the problem of migration and solubility of the additives. 

Cblorina.ted Pa.ra.ffins, The term chlotinated paraffins covers a variety of compositions. The prime variables are molecular weight of the starting paraffin and the chlorine content of the final product. Typical products contain from 12—24 carbons and from 40—70 wt % chlorine. Liquid chlotinated paraffins are used as plasticizers (qv) and flame retardants ia paint (qv) and PVC formulations. The soHd materials are used as additive flame retardants ia a variety of thermoplastics. In this use, they are combiaed with antimony oxide which acts as a synergist. Thermal stabilizers, such as those used ia PVC (see vinyl polymers), must be used to overcome the inherent thermal iastabiUty. 

Chem. Descrip. Zinc borate CAS 1332-07-6 EINECS/ELINCS 215-566-6 Uses Flame retardant, smoke suppressant for plastisols, coatings for cellulosics, textiles, and adhesives synergist in PVC and halogenated polyester formulations, and in elastomers, thermoplastic elastomers, polyamides, and polyolefins strong char promoter Properties Wh. free-flowing powd., nonhygroscopic 6 p avg. particle size 99.9% < 30 p sol. 0.5 g/100 ml water sp.gr. 2.50 bulk dens. 18.1 Ib/ff oil absorp. 39 ref. index 1.48 Zb -237 [Great Lakes]... 

Chem. Descrip. Zinc borate CAS 1332-07-6 EINECS/ELINCS 215-566-6 Uses Flame retardant, smoke suppressant for plastisols, coatings for textiles, adhesives synergist in PVC and halogenated polyester formulations, and in elastomers, thermoplastic elastomers, polyamides, and polyolefins strong char promoter... 

APP and APP-based systems are very effident halogen-free flame retardants mainly used in polyolefins (PE, PP), epoxies, polyurethanes, unsaturated polyesters, phenolic resins, and others. APP is a nontoxic, environment friendly material and it does not generate additional quantities of smoke due to intumescence. Compared to other halogen-free systems, APP requires lower loadings. In thermoplastic formulations, APP exhibits good processability, retention of good mechanical properties. 

Magnesium hydroxide can impart flame retardancy and smoke suppression to a wide variety of thermoplastics and elastomeric formulations. It is temperature... 

The char formers commonly used in intumescent formulations for thermoplastics are polyols such as pentaerythritol, mannitol, and sorbitol. However, exudation and water solubility are problems associated with these additives. Moreover, these additives are often not compatible with the polymeric matrix, and the mechanical properties of the formulations are then very poor. We have developed intumescent polyolefin-based formulations using charring polymers [thermoplastic polyurethane (TPU) and polyamide-6 (PA6)] as carbonization agents. " These formulated blends have improved mechanical properties compared with polymers loaded with classical flame retardants, and they avoid the problems... 

Flame Retardant for thermoset and thermoplastic formulations, intumescent systems... 

Adhesives can be separated into two general classes thermoplastics and thermosets. Thermoplastics can be formulated with halogen-containing and non-halogen-containing additives. Thermosets are commonly treated by adding flame retardants that chemically react with a resin precursor. O Table 13.12 lists flame retardants that are typically used. 

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