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The sigma bond between the 2‐phenyl pyridine head groups and the vinyl backbone of poly(2‐(4‐vinylphenyl)pyridine) allows for free rotation of the head groups in response to the polymer's environment (see image) and the hydrophobic vinyl backbone provides curvature for the formation of bilayer vesicles with a 1‐nm membrane thickness. The homopolymer vesicles act as a reservoir for both hydrophobic and hydrophilic molecules, individually or simultaneously.

The 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 (M w/M n = 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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