Biphasic coupling polymerization of 2,6-dimethylphenol using surface-active copper complex catalysts

✍ Scribed by Y.M Chung; W.S Ahn; P.K Lim

• Book ID: 104424539
• Publisher: Elsevier Science
• Year: 1999
• Tongue: English
• Weight: 175 KB
• Volume: 148
• Category: Article
• ISSN: 1381-1169
• DOI: 10.1016/s1381-1169(99)00161-2

✦ Synopsis

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. Ž . Coupling polymerization of 2,6-dimethylphenol to poly 2,6-dimethyl-1,4-phenylene oxide PPO was carried out in an 1:1 aqueous-chloroform biphasic mixture using Cu-surface active ligand complex catalysts. Bidentate ligands were superior to monodentate ligands in promoting the oxidative coupling possibly due to their higher surface-activity and ability to form a binuclear complex with two metal ions. In particular, N, N-dibutylethylenediamine complex of copper gave the highest reaction rates and produced a polymer with an average molecular weight of 48,000 in a 95% yield. Spontaneous phase separation induced by the surface-active ligand made it possible to recover the catalyst complex segregated at the middle emulsion layer in a compact form. Biphasic reaction with a suitable surface-active ligand was found to be more effective than homogeneous counterpart to promote the oxidative coupling reaction and was more favorable for forming higher molecular weight polymer products.