Chain extender
In polymer chemistry, a chain extender is a low molecular weight (MW) reagent that converts polymeric precursors to higher molecular weight derivatives. Often, it is convenient to prepare a polymer at an intermediate MW, which are suitable for solution- or melt-processing. At or near the final stages of production, the material is treated with a chain extender. Typically, chain extenders are bifunctional, i.e., they have two functional groups, which can link together two polymers. Representative classes of chain extenders are diglycidyl ethers, diols, diamines, or dianhydrides. Chain extenders are often applied to polyurethanes.[1]
Effects on Physical Properties
Chain extenders are often added to polymers improve their physical properties, as well as adding to their molecular weight. In particular, the addition of a chain extender will improve the thermal stability and viscosity of a polymer.[2][3]
References
- ^ Johannes Karl Fink, ed. (2013). Reactive Polymers Fundamentals and Applications. Elsevier. doi:10.1016/C2012-0-02516-1. ISBN 9781455731497.
- ^ Arruda, Liliane Cardoso; Magaton, Marina; Bretas, Rosário Elida Suman; Ueki, Marcelo Massayoshi (May 2015). "Influence of chain extender on mechanical, thermal and morphological properties of blown films of PLA/PBAT blends". Polymer Testing. 43: 27–37. doi:10.1016/j.polymertesting.2015.02.005.
- ^ Ongthip, Laksika; Chaiwutthinan, Phasawat; Chuayjuljit, Saowaroj; Boonmahitthisud, Anyaporn (2024-10-10). "Effects of chain extender types and contents on the properties of modified recycled polyethylene terephthalate". Journal of Applied Polymer Science. 141 (38). doi:10.1002/app.55971. ISSN 0021-8995.