Living Anionic Polymerization of the Amphiphilic Monomer 2-(4-Vinylphenyl)pyridine
2007; American Chemical Society; Volume: 40; Issue: 24 Linguagem: Inglês
10.1021/ma071349a
ISSN1520-5835
AutoresNam‐Goo Kang, Mohammad Changez, Jae‐Suk Lee,
Tópico(s)Coordination Chemistry and Organometallics
ResumoThe amphiphilic monomer 2-(4-vinylphenyl)pyridine (VPPy) has been successfully polymerized using a complex of sec-butyllithium (s-BuLi) with lithium chloride (LiCl) and coordination of VPPy with LiCl at −45 °C for 72 h without side reactions such as cross-linking and branching. However, it takes 3 days to complete the polymerization with 100% yield, and the polydispersity index (Mw/Mn = 1.15) was relatively broad. In contrast, the anionic polymerization using diphenylmethyl potassium (DPM-K) as the weak initiator was more feasible. The yield of the polymer reached 100% within 150 min at −78 °C, which significantly reduced polymerization time with a narrow molecular weight distribution below 1.1. To investigate their living nature and reactivity, the block copolymerization of VPPy with styrene, isoprene, 2-vinylpyridine, and methyl methacrylate were carried out by sequential anionic polymerizations without additives such as LiCl and Et2Zn. The resulting block copolymers of PVPPy-b-PMMA in tetrahydrofuran showed the microphase separation, which was confirmed by transmission electron microscopy.
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