Advertisement

If you have an ACS member number, please enter it here so we can link this account to your membership. (optional)

ACS values your privacy. By submitting your information, you are gaining access to C&EN and subscribing to our weekly newsletter. We use the information you provide to make your reading experience better, and we will never sell your data to third party members.

ENJOY UNLIMITED ACCES TO C&EN

Materials

Iodine Groups Help Create Diverse Conjugated Polymers

A postpolymerization technique for creating hyperbranched conjugated polymers maximizes compound diversity with minimal synthetic effort

by Rachel A. Petkewich
April 27, 2009 | A version of this story appeared in Volume 87, Issue 17

branching out
[+]Enlarge
Credit: Adapted from Wiley-VCH
A hyperbranched conjugated polymer backbone containing residual iodine groups (purple) is a jumping-off point for making diverse functionalized polymers.
Credit: Adapted from Wiley-VCH
A hyperbranched conjugated polymer backbone containing residual iodine groups (purple) is a jumping-off point for making diverse functionalized polymers.

In polymer chemistry, changing the functionality or properties of a polymer often means starting from scratch with a new monomer. Juan Tolosa, Chris Kub, and Uwe H. F. Bunz of Georgia Institute of Technology report a postpolymerization strategy for creating hyperbranched conjugated polymers that maximizes diversity with minimal synthetic effort (Angew. Chem. Int. Ed., DOI: 10.1002/anie200900980). Conjugated polymers have unique electronic properties that make them attractive materials for emerging technologies such as solar cells, plastic semiconductors, light-emitting diodes, and biosensors. In the new method, the researchers used Sonogashira coupling of a monomer containing an alkyne and two iodine substituents to create a poly(phenylene ethynylene) backbone studded with iodine groups. They then replaced the iodine groups with various alkynes under Sonogashira conditions and demonstrated how the modifications altered the fluorescence properties of the polymers. This strategy should allow researchers to develop libraries of compounds from a single polymer backbone for sensor materials, Bunz says. One approach he plans to try is to functionalize polymers with biological groups such as peptides.

Article:

This article has been sent to the following recipient:

0 /1 FREE ARTICLES LEFT THIS MONTH Remaining
Chemistry matters. Join us to get the news you need.