Stretchable polydimethylsiloxane/aligned electrospun cellulose acetate nanofibers composites with high transparency and fracture resistance

Abstract Polydimethylsiloxane (PDMS) is recognized as an excellent stretchable substrate in wearable electronics, due to its desirable properties such as tensile properties, transparency, thermal stability, non‐toxicity, and good biocompatibility. However, its limited fracture toughness and susceptibility to cracking significantly reduce the material's overall durability. In this study, the solution casting method was applied to prepare the nanofibers composites combined stretchable PDMS and aligned electrospun cellulose acetate (CA) to improve its mechanical properties and keep its transparency. The results showed that composites containing 3 wt% loadings of electrospun CA nanofibers exhibited a light transmittance exceeding 85% within the visible light range. Specifically, the PDMS/CA‐400 composites exhibited maximum improvements in comparison to pure PDMS. Notably, the tensile strength increased significantly from 2.1 to 3.0 MPa, while the toughness increased from 0.93 to 2.49 MJ/m 3 . In addition, the tensile strength of PDMS/CA‐400 composites with pre‐cut cracks increased from 0.2 to 1.4 MPa, and the fracture toughness increased from 14.78 to 174.42 kJ/m 3 , which were respectively 7 and 12 times compared to pure PDMS. Scanning electron microscope images showed that PDMS formed good interfacial interaction with CA nanofibers. This study introduces a novel method utilizing electrospun nanofibers to create transparent and fracture‐resistant stretchable composites, offering promising enhancements for the durability of wearable electronic devices. Highlights Explore the impact of the speed of receiving rollers on the degree of fiber arrangement. PDMS/CA‐400 composite material shows good light transmittance and high fracture resistance. The tight interface between the fiber and the matrix improves the optical transmission and mechanical properties of the composite materials.