Plant bio-inspired laminar cellulose-based foam with flame retardant, thermal insulation and excellent mechanical properties

• Published in: Journal of materials chemistry. A, Materials for energy and sustainability Materials for energy and sustainability, 2023-01, Vol.11 (3), p.1138-1147
• Main Authors: Hou, Yansu, Liao, Jianming, Huang, Luyao, Guo, Shasha, Zhang, Yuxiang, Liu, Zhan, Mo, Lihuan, Zhang, Xi, Li, Jun
• Format: Article
• Language: English
• Subjects: Borates; Buildings; Cellulose; Cellulose fibers; Energy efficiency; Fibers; Flame retardants; Heat transfer; Mechanical properties; Plastic foam; Thermal conductivity; Thermal insulation; Thermal management
• ISSN: 2050-7488; 2050-7496
• DOI: 10.1039/d2ta07646b

Plastic foam has received extensive attention as a potential thermal management material for energy-efficient buildings. However, manufacturing an environmental cellulose-based foam material with excellent mechanical properties, flame retardancy, and low thermal conductivity remains a great challenge. In the present work, we developed a novel and facile method to fabricate a cellulose-based foam from pulp fibers, cellulose nanofibrils (CNFs), and borates, in which borates acting as both flame retardants and crosslinkers build a strong porous and laminar structure with fibers. The resulting foam exhibits ultralow density (12.1 mg cm −3 ), high flame retardancy, outstanding thermal insulation ability (with a thermal conductivity of 48.6 mW mK −1 ), and excellent mechanical properties (with a specific modulus of 15.3 MPa cm 3 g −1 in the X direction). This work paves a new way for the synthesis of flame retardant insulation foam materials with great potential for practical applications in energy-efficient buildings. Plastic foam has received extensive attention as a potential thermal management material for energy-efficient buildings.