Overlooked Impact of Interchain H-Bonding between Cross-Links on the Mechanical Properties of Thermoset Polyurethane Elastomers

• DOI: 10.1021/acs.macromol.2c00873
• Publication Date: 2022-10-03T09:32:52Z
• Authors: Zhishuai Geng; Aimin Pang; Tengfei Ding; Xiaoyan Guo; Rongjie Yang; Yunjun Luo; Jinxian Zhai
• Keywords: Thermosetting polymer; Isocyanate

Thermoset polyurethane elastomers made from poly(3,3-bis(azidomethyl) oxetane with tetrahydrofuran) and various multifunctional isocyanate cross-linkers were compared to uncover a new mechanism of modulating the mechanical properties. Extra hydrogen bonding motifs, such as urethane or urea, built in proved essentially determine stiffness toughness elastomers, while covalent cross-linking densities both networks controlled strictly at same level. The impact interchain H-bonding on properties thermoset was unprecedently emphasized supported by evidence Fourier-transform infrared spectroscopy (FTIR), dynamic analysis (DMA), low-field nuclear magnetic resonance (LFNMR).