Enhanced flexibility and ablative performance of silicone rubber by constructing an interpenetrating zirconium-containing polysiloxane double network

To achieve uniform distribution of heteroatoms in silicone rubber, further simultaneously improving the flexi-bility and ablation resistance, polydimethylsiloxane with an interpenetrating zirconium-containing double-network (Zr-PDMS) was prepared. Compared to pure PDMS, the tensile strength and elongation-at-break of Zr-PDMS with interpenetrating double-network were increased by 615.33% and 124.23%, respectively, exhibiting significantly enhanced flexibility. Ablation analysis indicated that Zr-PDMS showed excellent anti-ablation performance, exhibiting obviously decreased mass ablation rate and charring rate. Most importantly, different from the crisp charred layers of pure PDMS as well as ZrO2 blends, Zr-PDMS formed stable and coherent charred layers after ablation tests. The improvement correlated to the in-situ formation of tetragonal ZrO2 in the char layer of Zr-PDMS, which could avoid the generation of defects in the ZrO2 blends char layer were discussed in detail. This work provided a new strategy of high flexible silicon rubber with excellent ablative performance, which can be expected to be well applied in the hypersonic spacecrafts.

Automated summary

In order to achieve uniform distribution of heteroatoms in silicone rubber and improve flexibility and ablation resistance, polydimethylsiloxane with an interpenetrating zirconium-containing double-network (Zr-PDMS) was prepared. Zr-PDMS showed significantly enhanced flexibility with increased tensile strength and elongation-at-break. It also exhibited excellent anti-ablation performance with decreased mass ablation rate and charring rate, forming stable and coherent charred layers after ablation tests.