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The main polycarbonate material is produced by the reaction of bisphenol A (BPA) and phosgene COCl 2. The overall reaction can be written as follows: The first step of the synthesis involves treatment of bisphenol A with sodium hydroxide, which deprotonates the hydroxyl groups of the bisphenol A. [6] (HOC 6 H 4) 2 CMe 2 + 2 NaOH → Na 2 (OC 6 ...
Solvent bonding differs from other plastic welding processes in that heating energy is generated by the chemical reaction between the solvent and thermoplastic, and cooling occurs during evaporation of the solvent. [5] Solvent bonding can be performed using a liquid or gaseous solvent.
The reaction of BPA with phosphorus oxychloride and phenol forms BADP, which is used as a liquid flame retarder in some high performance polymer blends such as polycarbonate/ABS mixtures that are used to form the casings for household electronics. [64]
A polycarbonate is an oxocarbon dianion consisting of a chain of carbonate units, where successive carbonyl groups are directly linked to each other by shared additional oxygen atoms. That is, they are the conjugate bases of polycarbonic acids , the conceptual anhydrides of carbonic acid , or polymers of carbon dioxide .
Devolatilization can be carried out when a polymer is in the solid or liquid phase, with the volatile components going into a liquid or gas phase. Examples are: Solid polymer, liquid phase: Extraction of caprolactam from polyamides with water. [4] Solid polymer, gas phase: Removal of ethylene from polyethylene via air or nitrogen in silos. [5]
Polycarbonate polyols are more expensive than other polyols and are thus used in more demanding applications. [31] [32] They have been used to make an isophorone diisocyanate based prepolymer which is then used in glass coatings. [33] They may be used in reactive hotmelt adhesives. [34] All polyols may be used to produce polyurethane prepolymers.
There are two examples each for liquid-liquid and liquid-in-liquid emulsion, either using one monomer or two. The most commonly used interfacial polymerization methods fall into 3 broad types of interfaces: liquid-solid interfaces, liquid-liquid interfaces, and liquid-in-liquid emulsion interfaces. [ 1 ]
In polymer chemistry, suspension polymerization is a heterogeneous radical polymerization process that uses mechanical agitation to mix a monomer or mixture of monomers in a liquid phase, such as water, while the monomers polymerize, forming spheres of polymer. [2] The monomer droplets (size of the order 10-1000 μm) are suspended in the liquid ...