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Polyurea is a type of elastomer that is derived from the reaction product of an isocyanate component and an amine component. The isocyanate can be aromatic or aliphatic in nature. It can be monomer , polymer , or any variant reaction of isocyanates, quasi-prepolymer or a prepolymer .
Spandex is mainly composed of a polyurea derived from the reaction of a diol and a diisocyanate. Two classes of spandex are defined by the "macrodiols". One class of macrodiols is the oligomer produced from tetrahydrofuran (i.e. polytetrahydrofuran).
block copolymer: A copolymer that is a block polymer. In the constituent macromolecules of a block copolymer, adjacent blocks are constitutionally different, ...
Polymethylene polyphenylene isocyanate (PPI), is a polyurea-based polymer derived from isocyanate monomers that is used in some glues, aerosol foams, plastics, paint and household products. [1] PPI is listed as a "hazardous agent" by the National Institutes of Health because it irritates skin and breathing passages at high concentrations.
Polyurea shows high T g, fair resistance to greases, oils, and solvents. It can be used in truck bed liners, bridge coating, caulk and decorative designs. Polysiloxane, siloxane-based polymers available in a wide range of physical states—from liquids to greases, waxes, resins, and rubbers.
Urea-formaldehyde (UF), also known as urea-methanal, so named for its common synthesis pathway and overall structure, [1] is a nontransparent thermosetting resin or polymer.It is produced from urea and formaldehyde.
TPU is a block copolymer consisting of alternating sequences of hard and soft segments or domains formed by the reaction of (1) diisocyanates with short-chain diols (so-called chain extenders) and (2) diisocyanates with long-chain diols. By varying the ratio, structure and/or molecular weight of the reaction compounds, an enormous variety of ...
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 ...