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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 .
Five common types of interfacial polymerization interfaces (from left to right): liquid-solid, liquid-liquid, and liquid-in-liquid emulsion. There are two examples each for liquid-liquid and liquid-in-liquid emulsion, either using one monomer or two.
The kinetics and rates of step-growth polymerization can be described using a polyesterification mechanism. The simple esterification is an acid-catalyzed process in which protonation of the acid is followed by interaction with the alcohol to produce an ester and water. However, there are a few assumptions needed with this kinetic model.
antidiuretic, diuresis, diuretic, dysuria, enuresis, polyurea, polyuria, uraemia/uremia, uremic, ureter, urethra, urology: urin-of or pertaining to urine, the urinary system Latin ūrīna, urine < Greek οὖρον (oûron), see ur-above. uriniferous: uter(o)-of or pertaining to the uterus or womb Latin uterus, womb, uterus uterus
To manufacture a polyaspartic ester, an amine is reacted with dialkyl maleate by the aza-Michael reaction. [8]Diethyl maleate is the usual maleate used. This converts the primary amines to secondary amines and also introduces bulky groups to the molecule which causes steric hindrance, slowing the reaction down.
The polyurethane urea elastomer (PUU), or poly (urethane urea) elastomer, is a flexible polymeric material that is composed of linkages made out of polyurethane and polyurea compounds. Due to its hyperelastic properties, it is capable of bouncing back high-speed ballistic projectiles as if the material had “hardened” upon impact.
In polymer chemistry, the term prepolymer or pre-polymer, refers to a monomer or system of monomers that have been reacted to an intermediate-molecular mass state. This material is capable of further polymerization by reactive groups to a fully cured, high-molecular-mass state.
In organic chemistry, neighbouring group participation (NGP, also known as anchimeric assistance) has been defined by the International Union of Pure and Applied Chemistry (IUPAC) as the interaction of a reaction centre with a lone pair of electrons in an atom or the electrons present in a sigma or pi bond contained within the parent molecule but not conjugated with the reaction centre.