Controlled Radical Polymerization: Cobalt Mediated Polymerization Processes with Column and its Future

In 1993 control radical polymerization of styrene, made a new concept in the controlled radical polymerization and it became possible to control molecular weight distribution of polymer of polymers to around one (NMCRP) [1]. Latter in 1997 atom transfer radical polymerization (ATRP and CMCRP) were reported for acrylates , styrene and vinyl acetate [2,3]. Today, the concept of control is concentrated on the chemical reactions directed by catalysts for number of specific monomers. In this sense control is implied to macromolecular micro structure its molecular weights or its distribution and stereo isomers. The control concept in this area is therefore related to the external control commonly used in solution, bulk, emulsion or suspension polymerizations. During last 50 years there has been little work on introducing new methods of polymerizations or new methods with different controls were related to diffusion, velocity, contact times or flow in the reaction . In this work a new method of polymerization with a different design has been introduced to permit these effects on controlling the process of polymerization. These effects are well beyond the stirring process in the reaction In addition the concept of volume, pressure and temperature is not the same as it is used in the polymerization. In this method the process itself plays an important effect on the reaction and rules over the stirring by diffusion, flow and contact times. Plate numbers, contact time, flow resistant, flow velocity influence the column stability and efficiency. Now each has acontrolling effect on the polymerization in the column.In this system surfaces area of particles used in the column makes millions of minute plates to create a new reaction sits and space for the polymerization

کلیدواژه ها:

Alumina column ، Clean polymer ، Cobalt-mediated radical polymerization ، Atom transfer radical polymerization ، adsorbent