Styrene flammability limits

METHYL STYRENE or 3-METHYL STYRENE or 4-METHYL STYRENE or m-METHYL STYRENE or p-METHYL STYRENE mixed Isomers (25013-15-4) C,H,o Flammable liquid. Forms explosive mixture with air (flash point 125°F/51°C). An inhibitor, usually 10 to 50 ppm of tert-butyl catechol, must be present in adequate concentrations to avoid explosive polymerization. Violent reaction with strong oxidizers, strong acids, peroxides and hydroperoxides. Incompatible with catalysts for vinyl or ionic polymers aluminum, aliuninum chloride, ammonia, aliphatic amines, alkanolamines, caustics, copper, halogens, iron chloride, metal salts (e.g., chlorides, iodides, sulfates, nitrates). The uninhibited monomer vapor may block vents and confined spaces by, forming a solid polymer material. On small fires, use dry chemical powder (such as Purple-K-Powder), foam, or CO extinguishers. a-METHYL STYRENE (98-83-9) C,H, Flammable liquid. Forms explosive mixture with air [explosion limits in air (vol %) 0.9 to 6.1 flashpoint 129°F/54°C autoignition temp 1066°F/574°C Fire Rating 2]. Easily polymerizable. Unless inhibited, forms unstable peroxides. Reacts with heat and/or lack of appropriate inhibitor concentration. Reacts with catalysts for vinyl or ionic polymerization, such as aluminum, iron chloride or 2,5-dimethyl-2,5-di(ieri-butylperoxy)hexane. Violent reaction with... 

Because of the abundance of styrene, polystyrene can be cheaply produced and used in many commercial qiplications. However, polystyrene is brittle and this limits tlieir utility in applications that requires good toughness properties. To overcome the brittleness problem, polystyrene is modified with rubber to improve its mechanical properties, etc. Polystyrene is also very flammable, flame retardants are used to lower the flammability of polystyrene. 

The preliminary study on the flammabihty of HUP-MMT compositions was performed by the determination of limiting oxygen indexes (LOI). The flame retardance was affected by styrene content in the resin and the type of clay used (Table 9.3). An additional amount of styrene has been added to some compositions in aim to improve the casting properties on the other hand the excess styrene makes the cured compositions more flammable due to the increased content of polystyrene (LOI = 18) and decreased of HUP (LOI = 24). The cured compositions containing MMT-Na as well as organoclays with DMDTA and ADA, showed... 

Health and safety limitations due to styrene (co-reactant and diluent) flammability. 

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