Lightweight and Flexible Phenolic Aerogels with Three-Dimensional Foam Reinforcement for Acoustic and Thermal Insulation

Organic aerogels with low density and developed porosity are extremely attractive for use in high-performance insulation, but their complicated fabrication, brittle structure, and poor flame retardancy greatly limit their practical applications. Herein, we report the preparation and properties of a lightweight and flexible phenolic aerogel reinforced with three-dimensional melamine foam (MF) through sol-gel polymerization of commercially available phenol formaldehyde. The wet gels with macroporous porosity and a strong network could be dried at ambient pressure without any volume shrinkage, which is extremely prior to the complicated supercritical drying. The introduction of MF can serve as a flexible skeleton to improve mechanical properties and simultaneously enhances the flame retardancy of aerogels. Additionally, the inherent excellent acoustic and thermal insulation properties of aerogels are maintained. The obtained aerogel possesses a low density (similar to 0.112 g.cm(-3)), high flexibility, excellent flame retardancy, hydrophobic property (135 degrees), and acoustic and thermal insulating property (0.021 W.m(-1).K-1 at room temperature). The current work may provide a simple, scalable, and economical approach for advancing the fabrication of organic aerogel materials for various applications.

Automated summary

Organic aerogels with low density and excellent flame retardancy, combined with three-dimensional melamine foam reinforcement, have been prepared to achieve a lightweight and flexible phenolic aerogel material with maintained acoustic and thermal insulation properties.