Bulk Energy Dissipation Driven Multiple Hydrogen‐Bonded Elastomer Enables High Stretchability, Extreme Softness and Superior Adhesion
Shuting Wang, Chunyu Wong, Yunsong Pang, Yongdong Wu, Zhenwei Yu, Xiaoliang Zeng, Rong Sun
Abstract
Abstract The inherent conflict between interfacial toughness and bulk energy dissipation in elastomers poses a challenge for achieving optimal adhesion. Here, this work reports a molecular design strategy for constructing poly(urethane‐urea‐thioctic acid) (PU‐TA) elastomers with superior adhesive properties (adhesion strength of 611 ± 22 kPa and adhesion energy of 2723 ± 82 J m −2 ), high stretchability (8579%), and excellent softness (low Young's modulus of 147 kPa). This is realized via introducing multiple hydrogen bonds (H‐bonds) into the PU‐TA elastomers: The H‐bonds at interfaces establish interfacial linkage, and the bulk H‐bonds inhibit the chain segments, resulting in high fracture energy. Furthermore, a correlation analysis demonstrates that bulk energy dissipation dominates role key in regulation of adhesion energy compared with interfacial toughness. This molecular‐level strategy provides a new sight into the design of superior adhesives suitable for diverse applications in the field of advanced packaging.