Prediction and mechanism of swelling-induced instability in polymeric gels

2018 Fiscal Year Final Research Report

• Project/Area Number: 16H04234
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Materials/Mechanics of materials
• Research Institution: Nagoya University (2018); Osaka University (2016-2017)
• Principal Investigator: Okumura Dai 名古屋大学, 工学研究科, 教授 (70362283)
• Co-Investigator(Kenkyū-buntansha): 内田 真 大阪市立大学, 大学院工学研究科, 准教授 (90432624) ; 伊田 翔平 滋賀県立大学, 工学部, 助教 (80610740) ; 田中 展 大阪大学, 工学研究科, 講師 (70550143)
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: 固体力学 / 材料力学 / ゲル / 不安定 / 膨潤

Outline of Final Research Achievements

In the present study, we developed the theories, numerical methods, and experimental approaches to predict and elucidate the mechanism of swelling-induced instability of polymeric gels. First, the characteristic of the extended Flory-Rehner model, developed by Okumura et al. (2016) using two scaling exponents, was analyzed under consideration of biaxial deformation and mass transport. In the analysis of swelling-induced instability, stable and efficient incremental approaches were investigated and proposed. Furthermore, experiments supported the validity and usefulness of the extended model. Accurate strain distribution measurement of the sample surface was achieved using a digital image correlation method.

Free Research Field

固体力学

Academic Significance and Societal Importance of the Research Achievements

ゲル材料は，ソフトマテリアルであり，水分を多く含み非常に柔らかい材料である．金属のようなハードマテリアルの変形や破壊に関する研究はこれまでにも進められているが，ゲル材料の研究は立ち遅れており，工学的な利用は今後益々増加すると見込まれるため，破損のきっかけになり得る特異な不安定変形に着目し，研究を進めることは，将来のソフトマテリアルの使いこなしを発展させるうえで非常に重要な研究成果に結びつくと期待される．