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Updated: Jul 16, 2026

Hydrophobic Salt-modified Nafion for Enzyme Immobilization and Stabilization
Published on: July 11, 2012
Unprecedented control over polymerization of n-hexyl isocyanate using an anionic initiator having synchronized
Jun-Hwan Ahn1, Yeong-Deuk Shin, G Yogendra Nath
1Department of Materials Science and Engineering and Center for Frontier Materials (BK21), Gwangju Institute of Science and Technology (GIST), 1 Oryong-dong, Buk-gu, Gwangju 500-712, Korea.
Abstract:
The living anionic polymerization of isocyanates carried out using conventional initiators is associated with side reactions due to rapid initiation rates as well as back-biting by the growing chain, resulting in a lack of control on the molecular weight (MW) and molecular weight distribution (MWD) of the polymers. Successful control over the reaction was possible by using additives that could prevent back-biting. We find an initiator in sodium benzanilide (Na-BA), which has a slow initiation rate combined with additive function, so that use of an external additive is eliminated. The initiator has resulted in polymers with high yields and an unprecedented control over the MW and MWD. It is possible to introduce a number of functionalities at the termini of the polymer by using Na-BA derivatives as well as suitable terminating agents, leading to macromonomer, reactive and chiral polymers, and chiral macromonomer in approximately 100% yields. In the process, the finding has expanded the scope of polyisocyanates in diverse applications.
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