Thermodynamics of reaction-induced phase separation and interfacial arrangement of fillers in cross-linked polymer alloy / filler composites

2023 Fiscal Year Final Research Report

• Project/Area Number: 21H01640
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 26030:Composite materials and interfaces-related
• Research Institution: University of Hyogo
• Principal Investigator: Kishi Hajime 兵庫県立大学, 工学研究科, 教授 (60347523)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: 複合材料 / フィラー / エポキシ / 相構造 / 界面 / 熱力学 / 平衡論 / 速度論

Outline of Final Research Achievements

The selective placement of fillers in the phase structures of polymer alloy composites can be explained by a common thermodynamic approach in which a mixed system selects a higher order structure to reduce the free energy of mixing. However, in the case of a networked polymer alloy with cross-linking (gelation), the mobility of the filler is frozen before a thermodynamic equilibrium state is reached and kinetic factors become important. In the case of fillers with strong molecular properties, such as those with alkyl group surface treatments, it was possible to explain their location in the network polymer alloy using the Hansen solubility parameter. On the other hand, for untreated inorganic fillers, acid-base interactions had to be taken into account. Furthermore, the mixing entropy term was found to be a major contributor to the interfacial arrangement of surface treated inorganic fillers.

Free Research Field

高分子系複合材料

Academic Significance and Societal Importance of the Research Achievements

異種ポリマー成分が接する架橋ポリマーアロイ共連続相の片方や界面への機能性フィラーの自己組織的配列を導く熱力学の構築を学術目的とする。特に、架橋ポリマーアロイ／フィラー複合材の硬化過程における自己組織化機構の解明を目指す。ネットワークポリマーアロイ共連続相構造をテンプレートとしてフィラーを自己組織的に連続配列させ得れば、極少量のフィラーにてチャンネル形成が可能となり機能性複合材の創出を導くと期待できる。