Precise synthesis of knotted ring polymers and the visualization of the topology

2014 Fiscal Year Final Research Report

• Project/Area Number: 24350056
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 一般
• Research Field: Polymer chemistry
• Research Institution: Nagoya University
• Principal Investigator: TAKANO Atsushi 名古屋大学, 工学(系)研究科(研究院), 准教授 (00236241)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: リングポリマー / 結び目 / トポロジー

Outline of Final Research Achievements

Telechelic polyisoprene (Mw=92k) was synthesized by an anionic polymerization and it was cyclized by end-to-end ring closure reaction in good and poor solvents under dilute conditions to synthesize unknotted/knotted ring polymers. The ring polymers obtained were separated from the cyclization reaction products by precipitational fractionation. By SEC-MALS measurements of the fractionated samples, it has been found that two ring polymers have almost the same molecular weight, while the ring formed in poor solvent reveals the smaller chain dimension than that of the ring formed in good solvent. These results clearly indicate the evidence of the formation of knotted ring polymers. To prepare polymer brush for the topology observation of a single molecule by AFM, grafting reaction was carried out to polyisoprene. From the AFM observation, architecture of knotted ring such as trefoil knot was clearly observed brushed ring formed in in poor solvent.

Free Research Field

高分子物性