Thermosetting polymer for dynamic nuclear polarization; Solidification of an epoxy resin mixture including TEMPO

熱硬化性樹脂の核スピン偏極; TEMPOラジカルを含むエポキシ樹脂の硬化プロセス

能田 洋平; 熊田 高之   ; 山口 大輔; 社本 真一  

Noda, Yohei; Kumada, Takayuki; Yamaguchi, Daisuke; Shamoto, Shinichi

TEMPOラジカルを含むエポキシ樹脂を対象に動的核スピン偏極を適用した。結果として、強磁場(3.35T)極低温(1.2K)環境において39%の水素核スピン偏極度を達成した。これは、標準試料としてしばしば用いられるTEMPO導入ポリスチレンとほぼ同等のものであった。TEMPOラジカル共存下でのエポキシ樹脂の硬化課程について、原料組成に基づく詳細な考察を行った。

We investigated the dynamic nuclear polarization (DNP) of typical thermosetting polymers (two-component type epoxy resins; Araldite(R) Standard or Araldite(R) Rapid) doped with TEMPO radical. The doping process was developed by carefully considering the decomposition of TEMPO during the solidification of the epoxy resin. With the resulting TEMPO-doped epoxy-resin samples, DNP experiments at 1.2 K and 3.35 T indicated a magnitude of a proton-spin polarization up to 39%. This polarization is similar to that (35%) obtained for TEMPO-doped polystyrene (PS), which is often used as a standard sample for DNP. We discussed the detail of the solidification process with considering the chemical composition of the initial epoxy resin mixture.