Side chains of copolymers can now be clicked into place thanks to a new method developed by Dutch researchers.  

Ulrich Schubert and co-workers at Eindhoven University of Technology, The Netherlands, started by making a copolymer backbone with para-fluorine groups called poly(pentafluorostyrene-b-styrene). Next they used click chemistry to graft simple side chains - amine-containing macromonomers - onto the backbone. In this reaction the para-fluorine groups on the backbone undergo nucleophilic substitution with the primary amines. Schubert found that a variety of functionalised polymers could then be added into the side-chains of the graft copolymer using both atom transfer radical polymerisation and ring opening polymerisation.

The extension of the side chains using functionalised polymers allows the properties of the graft copolymer to be fine tuned. 'The diversity makes this method so unique,' says Schubert. 'The scope of this approach is seemingly unlimited since it might be applied in any area that includes polymers,' he adds. 

Fluorinated polymers show high thermal stability, chemical resistance, good mechanical properties at high temperatures and low flammability. This makes them useful in microelectronic devices and antifogging agents. Schubert hopes his new polymers can be developed for a variety of functions including coupling catalysts to the polymer backbone and a drug carrier to target specific groups, for example sugars.

Sylvia Pegg