Preparation of hollow silica/PTFE fiber membrane with excellent thermal insulation performance by electrospinning

Flexible thermal insulation membrane plays a key role in outdoor wear of human body and thermal management of electronic products. This study used electrospinning to prepare thermal insulation hollow silica/polytetrafluoroethylene (HSi/PTFE) fiber membranes. HSi were prepared using tetraethylorthosilicate as the silicon source and hydrothermal carbon spheres as templates. A spinning solution of PTFE containing the HSi was used to prepare fiber membranes. The heat transfer resistance of the fiber is improved by embedding HSi into the PTFE fiber, resulting to improved heat insulation capability of the fiber membrane. The influence of HSi content on the thermal insulation performance of PTFE fiber membrane was studied. When the HSi content was 5 %, the fiber membrane showed the lowest thermal conductivity (0.0197 W/(m·K)), which was not only lower than most fiber thermal insulation materials, but also had excellent tensile properties (tensile deformation capacity of 168 %), which was convenient for practical application. In addition, this kind of fiber membrane also has high hydrophobicity (water contact angle of 147°), effectively reducing the influence of moisture on thermal insulation performance. This work presents innovative prospects for the future advancement of thermal insulation materials.