понедельник, 12 ноября 2012 г.
PVC foams (PVC)
PVC is manufactured like polystyrene. To start mixed blowing agent, methyl methacrylate and polyvinyl chloride latex.
These foams are obtained on the basis of PVC, as they contain ammonium carbonate blowing agent, methyl methacrylate, perchlorovinyl resin. By mixing the ingredients get songs, sliced into wafers. Then the plates are sent to the polymerization reactor in the liquid medium. Finished plates foamed at foaming agent.
PCV-2 and PCV-1 is of the type foam retardant materials, because they are under the influence of the local chamber ignition are off, and the last, all is self-extinguishing product.
PVC-production method based on the BZ inert gas saturation PVC paste with further gelling foam. The basis of the production of polyvinyl chloride foam laid ability perchlorovinyl resin dissolved without residue and form adhesive, which is the connecting track.
In addition to the rigid foam produces semi-rigid foam and PVC flexible foam. These types of foams have the lowest mechanical properties and are not recommended as construction aggregate.
This method is widely used for obtaining foam rubber and polyvinyl formaldehyde foam. Often to create mechanical and air foams use nitrogen as it diffuses poorly, non-flammable, non-toxic and inert. These foams have poor adhesion to anodized aluminum and steel in the molding process. They have not seen an adhesive similar to other materials. FPB and FRP-1 and exhibit a positive adhesion to fiberglass, asbestos and wood plastics.
In most cases, cellular plastics are gradually destroyed and have no clearly defined yield strength. Polyvinylchloride and polystyrene foams have a relatively high strength. Hard threshold and flexible foams and flexible. When wet strength values are below the plastic mesh.
In the CIS countries the production of polyvinyl chloride and polystyrene foams was organized after the war. Then developed a method of obtaining FF-FC (phenolic foams). On a large scale such foams started releasing later, and later developed a method of manufacture of polystyrene foam bespressovogo.
Подписаться на:
Комментарии к сообщению (Atom)
Комментариев нет:
Отправить комментарий