Tad-indole click chemistry fleetly construct silicone elastomers with controllable mechanical and antibacterial properties

Abstract

As a type of heterochain polymer materials, silicone elastomers possess unique properties due to the high temperature-stable and low temperature-docile Si-O bonds. However, the reactions of construct silicone elastomers include hydrosilylation reaction, silanol condensation reaction, free radical reaction, etc. are typically constrained by external stimuli including catalysts, temperature, and humidity. Therefore, it is of great significance to develop novel strategies for cross-linking Si-O bonds without relying on external stimuli and to rapidly construct silicone elastomers. Herein, click chemistry was employed to bridge the lateral amino-dimethylsiloxane and fleetly form silicone elastomers. The siloxane containing lateral amino groups was initially modified by indole-5-formaldehyde (IC) through a Schiff base reaction. The synergistic effects between natural antifouling agent of the indole groups and the five-membered nitrogen heterocyclic ring of TAD structures endowed outstanding antibacterial properties. Moreover, the presence of indole groups made the elastomers 0% transmittance in UV region, which could be used as UV protective materials. The development and utilization of TAD-indole click chemistry with fast reaction speed, high selectivity and without external stimulus for the elastomer preparation is very valuable. It may give new functions and expand new application fields of silicones.