2026-07-15 東北大学

図1.分子鎖再結合によるプラスチック強度回復を示す応力-ひずみ曲線。
<関連情報>
- https://www.tohoku.ac.jp/japanese/2026/07/press20260715-02-recycling.html
- https://www.sciencedirect.com/science/article/pii/S1359835X26004641
分子量駆動型鎖延長による機械的強度の回復:ポリマーリサイクルへのフォックス・フローリー型アプローチ Molecular-weight–driven recovery of mechanical strength via chain extension: a Fox–Flory-type approach to polymer recycling
Koya Otsuka, Zhenjin Wang, Hiroki Kurita, Fuminori Kondo, Masato Ikeda, Fumio Narita
Composites Part A: Applied Science and Manufacturing Available online: 13 June 2026
DOI:https://doi.org/10.1016/j.compositesa.2026.110017
Abstract
The rapid increase in plastic waste necessitates effective recycling strategies for high-performance polymers like polybutylene terephthalate (PBT), which is prone to hydrolytic degradation and significant loss of mechanical properties. This study presents a straightforward melt-blending method utilizing 1,4-phenylene diisocyanate (PPDI) to restore degraded PBT. By adding 7 mol% PPDI, we successfully recovered tensile strength and elongation to levels nearly equivalent to those of pristine PBT, achieved via chain-extension reactions that form urethane and amide bonds. Additionally, we observed that the relationship between ultimate tensile strength and molecular weight followed a Fox–Flory-type correlation, highlighting a quantitative connection between molecular structure and strength recovery. This study not only offers a practical recycling method but also establishes a new framework for predictive circular polymer design.


