Flexible and superhydrophobicity polylactic acid hollow fiber aerogels for thermal insulation

Abstract

Thermal insulating bio-based aerogels with robust compression properties are highly desirable for meeting extreme dangerous heat environments. However, the large-scale application of conventional aerogels are still limited by their inherent brittleness. Herein, we design an thermal insulated polylactic acid based aerogels with 3D microstructure, owning outstanding cyclic compression performance and superhydrophobic ability etc. The results show SC-H-PLA aerogels have ultra-high hydrophobicity (water contact angle 154.3°), porosity (∼91 %), density (23.034 mg/cm3), and lower thermal conductivity (0.029 W/(m k)). At the same time, the compression stress of SC-H-PLA aerogels reaches 22.17 ± 0.42 kPa at 60 % compression. After 100 cycles, the compressive stress of SC-H-PLA aerogels owns 18.71 ± 0.36 kPa, maintaining 84.92 % of the original stress. When simulating extreme ambient temperature (cold source -50 °C, heat source 80 °C), the temperature difference between the upper and lower surface of SC-H-PLA aerogel can reach 44 °C and 66 °C. This work provides an new avenue for designing thermal insulated materials with excellent toughness and thermal insulation in extreme environments.