In polymer chemistry, a comonomer refers to a polymerizable precursor to a copolymer aside from the principal monomer. In some cases, only small amounts of a comonomer are employed, in other cases substantial amounts of comonomers are used. Furthermore, in some cases, the comonomers are statistically incorporated within the polymer chain, whereas in other cases, they aggregate. The distribution of comonomers is referred to as the "blockiness" of a copolymer. 1-Octene, 1-hexene, and 1-butene are used comonomers in the manufacture of polyethylenes. The advantages to such copolymers has led to a focus on catalysts that facilitate the incorporation of these comonomers, e.g., constrained geometry complexes.[1]

In this conversion, 1-hexene (red) is a comonomer in the formation of a modified polyethylene.

Comonomers are often employed to improve the plastification of polymeric materials, i.e. the flexibility of the polymer. Unlike traditional plasticizers, comonomers are not leachable. In other cases, comonomers are used to introduce crosslinking. Divinylbenzene, for example, when copolymerized with styrene, gives a crosslinked polystyrene.[2]


  1. Chum, P. Steve; Swogger, Kurt W. (2008). "Olefin polymer technologi geography and Recent Progress at the Dow Chemical Company". Progress in Polymer Science. 33 (8): 797–819. doi:10.1016/j.progpolymsci.2008.05.003.
  2. Hans-Georg Elias "Plastics, General Survey"in Ullmann's Encyclopedia of Industrial Chemistry 2005, Wiley-VCH, Weinheim. doi:10.1002/14356007.a20_543
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.