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A polyurethane is typically produced by reacting a polymeric isocyanate with a polyol. [3] Since a polyurethane contains two types of monomers, which polymerize one after the other, they are classed as alternating copolymers. Both the isocyanates and polyols used to make a polyurethane contain two or more functional groups per molecule.
Thiocarbamate pesticide, liquid, flammable, toxic, flashpoint less than 23 °C UN 2773 (UN No. no longer in use) Phthalimide derivative pesticides , solid, toxic, n.o.s. (UN No. no longer in use) [ 1 ]
Cured PURs are segmented copolymer polyurethane-ureas [2] exhibiting microphase-separated morphologies. One phase is derived from a typically flexible (subambient glass transition temperature, T g) polyol that is generally referred to as the “soft phase”. Likewise the corresponding “hard phase” is born from the di- or polyisocyanates ...
For example, in the United States flammable liquids, by definition, have a flash point below 100 °F (38 °C)—where combustible liquids have a flash point above 100 °F (38 °C). Flammable solids are solids that are readily combustible, or may cause or contribute to fire through friction.
The introduction of these chemicals came about after the tragic death of children wearing brushed rayon fabric that would ignite easily. The US enacted the Flammable Fabrics Act passed in 1953 after which, flame retardants were mandated to be added to many children's items, including pajamas. While flame retardants are shown to decrease the ...
Spray foam insulation extruding from a duct. Spray foam (expanding foam in the UK) is a chemical product created by a chemical reaction of two component parts, commonly referred to as side A and side B. [1] Side A contains very reactive chemicals known as isocyanate.
Tris(chloropropyl) phosphate (commonly abbreviated TCPP) is a chlorinated organophosphate flame retardant commonly added to polyurethane foams. [1] Comparatively minor amounts are used in PVC and EVA .
To achieve this, one can create an endothermic environment, produce non-combustible products, or add chemicals that would remove fire-propagating radicals (H and OH), to name a few. These specific chemicals can be added into the polymer molecules permanently (see Intrinsically Fire-Resistant Polymers) or as additives and fillers (see Flame ...