Glass transition and interfacial dynamics in stacked thin polymer films

2018 Fiscal Year Final Research Report

• Project/Area Number: 16H04036
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Biological physics/Chemical physics/Soft matter physics
• Research Institution: Ritsumeikan University
• Principal Investigator: Fukao Koji 立命館大学, 理工学部, 教授 (50189908)
• Co-Investigator(Kenkyū-buntansha): 瀧川 佳紀 名古屋工業大学, 工学(系)研究科(研究院), 助教 (20755483)
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: ガラス転移 / 高分子薄膜 / 界面相互作用 / α過程 / 誘電緩和測定 / 中性子反射率測定

Outline of Final Research Achievements

The relation between the change in the dynamics and that in the interfacial structure has been investigated for stacked thin polymer films by using dielectric relaxation spectroscopy and neutron reflectivity measurements. For stacked PMMA thin films, the dielectric relaxation strength of the alpha-process is decreased and the peak temperature of the dielectric loss spectra is increased with increasing annealing time. The increase in roughness at the interface between d-PMMA layer and h-PMMA layer has been observed from the neutron reflectivity measurements on alternately stacked thin films of d-PMMA and h-PMMA. Furthermore, this time evolution of the interfacial structure at the interface occurs on a time scale similar to that of the time evolution of some parameters of the alpha-process obtained by dielectric relaxation spectroscopy. Therefore, the change in the interfacial structure could be a physical origin for the change in the dynamics of the alpha-process in thin polymer films.

Free Research Field

高分子物理学

Academic Significance and Societal Importance of the Research Achievements

表面・界面相互作用によって、高分子薄膜のガラス転移温度が如何に変化するのかを明らかにし、その制御を可能とすることができれば、高分子材料の産業界での応用にとって大変重要な進展である。本研究では、中性子反射率・誘電緩和測定を用いて、その目的を達成する一つの可能性が示されており、十分な学術的かつ社会的意義を有すると言える。