Development of High Thermal Conductive polymers based on Beads-On-String-Shaped Design

2022 Fiscal Year Final Research Report

• Project/Area Number: 21K19003
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 35:Polymers, organic materials, and related fields
• Research Institution: Kyoto Institute of Technology
• Principal Investigator: Naka Kensuke 京都工芸繊維大学, 分子化学系, 教授 (70227718)
• Project Period (FY): 2021-07-09 – 2023-03-31
• Keywords: かご型シルセスキオキサン / ポリウレア / ポリイミド / 低誘電率

Outline of Final Research Achievements

POSS main-chain polymers with varying lengths and polarities of cross-linking sites were prepared by polymerization of cage silsesquioxane (POSS) monomers having two amino groups with various diisocyanates to develop a transparent resin with high thermal conductivity. The thermal conductivity of the polymers was about 0.25 W/m-K, which was not necessarily an improvement in thermal conductivity. However, it was found that the gelation progressed with the progress of polymerization at the similar concentration as those of ordinary low-molecular-weight oil gelating agents. In addition, the combination of the POSS units and urea groups successfully provided unique polymeric materials with low dielectric constants and low dissipation factors.

Free Research Field

高分子合成

Academic Significance and Societal Importance of the Research Achievements

得られたフィルムの物性を評価したところ熱伝導率は高くても0.25 W/m・K程度と必ずしも熱伝導性が向上するものではなかった。しかしながら、フィルムの比誘電率および誘電正接の測定を行った結果、高分子の構造によっては比誘電率が3以下・誘電正接が0.01以下となるものがあり、一般的には高誘電材料であるポリウレアを低誘電率・低誘電正接化できることに成功した。このような特性は剛直で嵩高い疎水性ブロックであるDDSQと水素結合性官能基を含む架橋部位が数珠玉のように連なった構造に由来することを示す結果であり、既存の材料では達成不可能なトレードオフを解消した材料設計指針に寄与するものである。