Ad
related to: how is polyvinyl alcohol made using common materials examples
Search results
Results from the WOW.Com Content Network
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 .
Polyvinyl acetate used further for polyvinyl alcohol is manufactured by radical polymerization in methanol solution. Liquid polybutadienes are made by anionic or radical polymerization in hydrocarbon solutions. Butyl rubber (IIR) by low temperature cationic copolymerization of isobutylene with isoprene in ethylene or methylchloride solution.
Vinyl polymers are the most common type of plastic. Important examples can be distinguished by the R group in the monomer H 2 C=CHR: Polyethylene R = H; polypropylene from propylene, R = CH 3; Polystyrene is made from styrene, R = C 6 H 5; Polyvinyl chloride (PVC) is made from vinyl chloride, R= Cl; Polyvinyl acetate (PVAc) is made from vinyl ...
Some grades of polyvinyl alcohol and other water-soluble polymers can promote emulsion polymerization even though they do not typically form micelles and do not act as surfactants (for example, they do not lower surface tension). It is believed that growing polymer chains graft onto these water-soluble polymers, which stabilize the resulting ...
Vinyl alcohol, also called ethenol (IUPAC name; not ethanol) or ethylenol, is the simplest enol. With the formula C H 2 CH O H , it is a labile compound that converts to acetaldehyde immediately upon isolation near room temperature. [ 1 ]
The plastic kits and covers are mostly made of synthetic polymers like polythene, and tires are manufactured from polybutadienes. [1] However, due to the environmental issues created by these synthetic polymers which are mostly non-biodegradable and often synthesized from petroleum, alternatives like bioplastics are also being considered.
Other materials are also used to make a superabsorbent polymer, such as polyacrylamide copolymer, ethylene maleic anhydride copolymer, cross-linked carboxymethylcellulose, polyvinyl alcohol copolymers, cross-linked polyethylene oxide, and starch grafted copolymer of polyacrylonitrile to name a few. The latter is one of the oldest SAP forms created.
Polyvinyl acetate is also the raw material to make other polymers like: Polyvinyl alcohol −[HOCHCH 2 ]−: Polyvinyl acetate is partially or completely hydrolysed to give polyvinyl alcohol. This reversible saponification and esterification reaction was a strong hint for Hermann Staudinger in the formulation of his theory of macromolecules .
Ad
related to: how is polyvinyl alcohol made using common materials examples