Details

Autor(en) / Beteiligte

• Xu, JianHua
• Chen, JiaoYang
• Zhang, YaNa
• Liu, Tong
• Fu, JiaJun

Titel

A Fast Room‐Temperature Self‐Healing Glassy Polyurethane

Ist Teil von

• Angewandte Chemie International Edition, 2021-03, Vol.60 (14), p.7947-7955

Auflage

International ed. in English

Ort / Verlag

Germany: Wiley Subscription Services, Inc

Erscheinungsjahr

2021

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• We designed and synthesized a colorless transparent glassy polyurethane assembled using low‐molecular‐weight oligomers carrying a large number of loosely packed weak hydrogen bonds (H‐bonds), which has a glass transition temperature (Tg) up to 36.8 °C and behaves unprecedentedly robust stiffness with a tensile Young's modulus of 1.56±0.03 GPa. Fast room‐temperature self‐healing was observed in this polymer network: the broken glassy polyurethane (GPU) specimen can recover to a tensile strength up 7.74±0.76 MPa after healing for as little as 10 min, which is prominent compared to reported room‐temperature self‐healing polymers. The high density of loose‐packed hydrogen bonds can reversibly dissociate/associate below Tg of GPU (that is secondary relaxation), which enables the reconfiguration of the damaged network in the fractured interfaces, despite the extremely slow diffusion dynamics of molecular chains under room temperature. This GPU shows potential application as an optical lens. A glassy polyurethane (GPU) assembled by linear oligomers carrying abundant weak hydrogen bonds is presented. It is not only colorless, transparent, and stiff, but also shows fast room‐temperature self‐healing owing to the high mobility of the loosely packed hydrogen bonds in the glassy state. Molecular‐level events that occur in this process are established.