Highly stretchable, soft and sticky PDMS elastomer by solvothermal polymerization process

Siloxane rubber shows attractive properties of high stability, elasticity and transparency. Besides, the regulation of its properties renders it widely used in many application fields. However, most of the reported performance improvement methods of siloxane rubber focus on the change of chemical composition of siloxane rubber, including the design of molecular chain and the introduction of other compounds, etc. Such a strategy is still faced with many limitations in practical application. In this work, on the premise of not changing the chemical composition of siloxane rubber, we propose a facile solvothermal polymerization process to change the structure of cross-linking networks, so as to obtain the siloxane rubber with controllable mechanical properties. Compared to the normal curing method, we realized polydimethylsiloxane elastomer (PDMS) with maximum elongation of more than 3,000% (> 10 times of normally cured one) and tensile modulus lower than 0.15 MPa (< 1/10 of normally cured one). In addition to superior stretchability, it gains extra high softness, stickiness and sensitive response to organic solvents. Based on our solvothermal cured PDMS, its applications in oil collection and organic solvent sensor have been demonstrated. It is expected that this method can be readily utilized widely and shows great application potentials.

Automated summary

A new solvothermal polymerization process was proposed in this study to modify the cross-linking network structure of siloxane rubber, achieving PDMS elastomer with controllable mechanical properties. Compared to conventional curing methods, this approach resulted in higher elongation and lower tensile modulus for the PDMS elastomer.