posted on 2021-09-16, 11:36authored byXinru Guo, Fei Gao, Fengbiao Chen, Jiang Zhong, Liang Shen, Cong Lin, Yangju Lin
Here,
we report the fabrication of a dynamic enamine-one bond based
vitrimer through amino-yne click chemistry. In contrast to amine-acetoacetate
condensation, the amino-yne click reaction yields a dynamic enamine-one
motif that is composed of cis/trans (3:1) isomers and has a relatively lower activation energy (35 ±
3 kJ/mol vs 59 ± 6 kJ/mol), owing to the absence of a methyl
substituent. The resulting vitrimer network has superior mechanical
properties and faster dynamic exchange than that of a reference vitrimer
derived from amine-acetoacetate condensation, and they are attributed
to the fewer network defects and the less sterically hindered exchange
reaction, respectively. Lastly, the efficient amino-yne click reaction
is demonstrated to be compatible with the secondary-amine substrate,
which has a low reactivity toward the amine-acetoacetate condensation.
The efficient and side product-free amino-yne reaction offers a powerful
chemical tool for vitrimer fabrication and is potentially desirable
for sealing and adhesion applications.