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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 ...
Alcohols react with phosgene to yield carbonate esters according to the following reaction: 2 ROH + COCl 2 → ROC(O)OR + 2 HCl. Phenols react similarly. Polycarbonate derived from bisphenol A is produced in this manner. This process is high yielding.
It is a colourless solid which is soluble in most common organic solvents, but has very poor solubility in water. [2] [7] BPA is produced on an industrial scale by the condensation reaction of phenol and acetone. Global production in 2022 was estimated to be in the region of 10 million tonnes. [8]
Polyvinyl alcohol (PVOH, PVA, or PVAl) is a water-soluble synthetic polymer. It has the idealized formula [CH 2 CH(OH)] n. It is used in papermaking, textile warp sizing, as a thickener and emulsion stabilizer in polyvinyl acetate (PVAc) adhesive formulations, in a variety of coatings, and 3D printing. It is colourless (white) and odorless.
The continuous water phase is an excellent conductor of heat, enabling fast polymerization rates without loss of temperature control. Since polymer molecules are contained within the particles, the viscosity of the reaction medium remains close to that of water and is not dependent on molecular weight.
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.
A mix of isopropyl alcohol (1/3) and water (2/3) in a spray bottle. Isopropyl alcohol ranges from 50 to 90 percent purity. The higher the number the better the deicing capability.
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 .