Talk:Step-growth polymerization

From Wikipedia, the free encyclopedia
Jump to: navigation, search
WikiProject Polymers
WikiProject icon Step-growth polymerization is within the scope of WikiProject Polymers which aims to improve the coverage of polymer-related articles in Wikipedia. If you are interested, you may visit the project page and join with us. Feel free to leave messages at the project talk page. WikiProject icon
 
WikiProject Chemistry (Rated Start-class, Mid-importance)
WikiProject icon This article is within the scope of WikiProject Chemistry, a collaborative effort to improve the coverage of chemistry on Wikipedia. If you would like to participate, please visit the project page, where you can join the discussion and see a list of open tasks.
Start-Class article Start  This article has been rated as Start-Class on the project's quality scale.
 Mid  This article has been rated as Mid-importance on the project's importance scale.
 

Step growth polymerization and Condensation polymerization are absolutely same things but the name Condensation polymerization is acceped more in the field of polymer science though some references are there that use this old name Step growth. The process releases simple molecules (mainly water) i.e. loss of water takes place which directly and commonly known as condensation process, furthermore in some condensation polymerization the reaction is very rapid (fraction of seconds) EX: Simply adding common salts to any white synthetic adhesive quickly form bonds and releases water, hence it is not a step by step growth always. The name Condensation polymerization is more appropriate.

Sorry, but you are wrong: a "step-growth polymerization" isn't always a "condensation polymerization": for example, polyurethane is an "addition polymer" but is prepared through a "step-growth polymerization". In fact the two terms are referred to two different points of view:
  • the distinction between "addition polymerization" and "condensation polymerization" was introduced by Wallace Hume Carothers in 1929, and are referred to the type of products, respectively:
  • a polymer only (addition)
  • a polymer and a molecule with a low molecular weight (condensation)
See: W. H. Carothers, "Journal of American Chemical Society", 1929, 51, 2548 - Paul J. Flory, "Principles of Polymer Chemistry", Cornell University Press, 1953, p.39. ISBN 0801401348
  • the distinction between "step-growth polymerization" and "chain-growth polymerization" was introduced by Paul Flory in 1953, and are referred to the reaction mechanisms, respectively:
  • by functional groups (step-growth polymerization)
  • by free-radical or ion (chain-growth polymeryzation)
See: Susan E. M. Selke, John D. Culter, Ruben J. Hernandez, "Plastics packaging: Properties, processing, applications, and regulations", Hanser, 2004, p.29. ISBN 1569903727
--Aushulz (talk) 09:54, 23 July 2009 (UTC)

Figure comparing chain-growth versus step-growth[edit]

In the figure comparing the molecular weight of chain-growth vs. step-growth as a function of conversion, the label for the black line is for living chain-growth while in the caption for the figure it says chain-growth. It is not possible to show this curve without specifying what type of chain-growth polymerization is in question. For example, in free radical polymerization the molecular weight as a function of conversion decreases (see Fundamental Principles of Polymeric Materials by Stephen Rosen). I propose that the caption be modified to read: "...between step-growth and living chain-growth polymerization." Sturgman (talk) 16:03, 30 July 2010 (UTC)

Done. But for the case with termination, could you specify the page (and edition) in Rosen. Thanks. Dirac66 (talk) 01:39, 31 July 2010 (UTC)

Functional Groups[edit]

What about mention the functional groups that chemist are limited to on step growth?

-- edmirsilva (talk) —Preceding undated comment added 02:47, 25 September 2010 (UTC).