Correlation between Local Molecular Mobility and Mechanical Properties in Ionic Polymers

2017 Fiscal Year Final Research Report

• Project/Area Number: 16K17958
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Polymer/Textile materials
• Research Institution: Gifu University
• Principal Investigator: YOHEI Miwa 岐阜大学, 工学部, 准教授 (10635692)
• Project Period (FY): 2016-04-01 – 2018-03-31
• Keywords: エラストマー / アイオノマー / イオン / ガラス転移温度 / 電子スピン共鳴 / 動的架橋 / 自己修復

Outline of Final Research Achievements

Local glass transition temperatures (Tg) for ionic aggregates, in poly(ethylene-co-methacrylic acid) (EMAA) ionomers plasticized with lauric acid (LA), have been position-selectively measured by electron spin resonance (ESR). This ESR study reveals that a restricted shell region surrounds the rigid ionic core with a thickness of approximately 10 Å. Here, we directly observed that the shell region is preferentially plasticized by LA. When the local shell region Tg decreases to below room temperature, while the weight fraction of LA simultaneously increases, the specimen becomes remarkably stretchable during the tensile test.
We developed an ionically crosslinked polyisoprene elastomer in which the ionic moieties are continuously hopping between ionic aggregates at room temperature. This elastomer spontaneously self-heals. Furthermore, it behaves like a strong and tough elastic material under rapid deformation, but acts like a highly stretchable material under slow deformation.

Free Research Field

高分子科学