Hyperbranched Poly(ferrocenylphenylenes): Synthesis, Characterization, Redox Activity, Metal Complexation, Pyrolytic Ceramization, and Soft Ferromagnetism

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• 作者：Jianbing Shi ; Bin Tong ; Zhen Li ; Jinbo Shen ; Wei Zhao ; Huanhuan Fu ; Junge Zhi ; Yuping Dong ; Matthias Hä ; ussler ; Jacky W. Y. Lam ; Ben Zhong Tang
• 刊名：Macromolecules
• 出版年：2007
• 出版时间：November 13, 2007
• 年：2007
• 卷：40
• 期：23
• 页码：8195 - 8204
• 全文大小：268K
• 年卷期：v.40,no.23(November 13, 2007)
• ISSN：1520-5835

文摘

Hyperbranched poly(ferrocenylphenylenes) (hb-PFPs) with high molecular weights were synthesizedby the copolycyclotrimerizations of (E,E)-1,1'-bis[2-(4-ethynylphenyl)vinyl]ferrocene (1) with (E)-1-[2-(4-ethynylphenyl)vinyl]ferrocene (2) catalyzed by TaCl₅-Ph₄Sn at room temperature in high yields (up to 97%).Effects of reaction conditions, such as monomer and catalyst concentrations, reaction time and molar feed ratio(r_1/2), on the copolycyclotrimerization were investigated. Solubility of the copolymer is decreased with an increasein its content of diyne component (N₁/N₂). The hb-PFPs were characterized by IR, NMR, UV, CV and TGAanalyses. The copolymers are redox active, whose oxidation potentials are decreased with an increase in N₁/N₂.They are thermally stable, losing ~5% of weights when heated to 384-400 C and retaining ~70% of weightswhen pyrolyzed at 1200 C. The complexation with cobalt carbonyl further metallizes the hb-PFPs and the pyrolyticceramization of the cobalt-polymer complexes yields soft ferromagnetic ceramics with high magnetizability (M_sup to ~126 emu/g) and low coercivity (H_c down to ~0.068 kOe).