Atom Transfer Radical Polymerization of Styrene Using Various Onium Salts as Ligands

Abstract

The heterogeneous atom transfer radical polymerization of styrene using various onium salts as ligands in the presence of (1‐chloroethyl or 1‐bromoethyl) benzene [PEX (X = Cl, Br)] was investigated. The rate of polymerization using these onium salts as ligands exhibited non‐linear first‐order kinetics with respect to the monomer. The experimental molecular weights increased linearly with monomer conversion and were close to the calculated values for most of these catalytic systems. The polydispersities of the resulted polymers were around 1.1–1.5. Allylic substituent on the phosphorus favored the control of polymerization. The FeCl₂ · 4H₂O/hexadecyl trimethyl ammonium bromide yield the lowest rate of polymerization, which maybe due to the excess of Fe³⁺. Using mixed halogen initiation system PEBr/FeCl₂, poor control of ATRP of styrene in the presence of onium salts was observed except for triphenylbutyl phosphonium bromide.

Keywords:

• Onium salts
• Atom transfer radical polymerization
• Styrene
• Ligand

Acknowledgments

We gratefully acknowledge the National Nature Science Foundation of China (No. 20176033) and the Nature Science Foundation of Jiangsu Province (No. BK2001141) for support for this work.