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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.
Polyurethane dispersion, or PUD, is understood to be a polyurethane polymer resin dispersed in water, rather than a solvent, although some cosolvent may be used.Its manufacture involves the synthesis of polyurethanes having carboxylic acid functionality or nonionic hydrophiles like PEG (polyethylene glycol) incorporated into, or pendant from, the polymer backbone. [1]
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 ...
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 .
Thermoplastic polyurethane (TPU) is any of a class of polyurethane plastics with many properties, including elasticity, transparency, and resistance to oil, grease, and abrasion. Technically, they are thermoplastic elastomers consisting of linear segmented block copolymers composed of hard and soft segments.
Water-reactive substances [1] are those that spontaneously undergo a chemical reaction with water, often noted as generating flammable gas. [2] Some are highly reducing in nature. [ 3 ] Notable examples include alkali metals , lithium through caesium , and alkaline earth metals , magnesium through barium .
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 ...
To be added to that list, the product must be tested by Wildland Fire Chemical Systems, a division of the National Technology and Development Program, a process that can take up to two years. [18] Phos-Chek is a brand of long-term retardant currently approved for wildland fire use. [ 19 ]