Multifunctional Lightweight Guanidine Phosphate/Poly(Vinyl Alcohol) Melamine-Based Hybrid Foam for Superior Thermal Insulation and Flame Retardancy

Abstract

In the field of building energy conservation, advanced thermal insulation materials with low thermal conductivity and excellent flame retardancy have always been a research emphasis. This work proposes a facile strategy for fabricating a hybrid foam based on the skeleton of melamine-formaldehyde (MF) foam, and the GP/poly(vinyl alcohol) (PVA) tightly adheres to the skeleton with the capillary force of MF. The combination of guanidine phosphate (GP) and PVA provides outstanding thermal insulation performance and infrared stealth property to the hybrid foam, and the existence of GP endows the hybrid foam with superior flame retardancy and charring ability. The tensile and compression strength of the GP/PVA@MF hybrid foams have significantly improved. The 1.5 wt % GP/10 wt % PVA@MF (MF-1.5) foam has an ultra-low thermal conductivity value of 0.0293 W m–1 K–1 due to the rational three-dimensional (3D) pore microstructure. Meanwhile, the MF-1.5 foam achieves a V-0 rating in the vertical burning (UL-94) test and a limiting oxygen index of 32.4%. Furthermore, the cone calorimeter results show that the addition of GP significantly reduces total heat release and total smoke release. The GP/PVA@MF hybrid foam will be a multifunctional material with outstanding thermal insulation and flame retardancy, showing a great application in the military and civilian fields.

Effortless impregnation method for melamine formaldehyde foams exhibiting elevated thermal stability and exceptional flame retardant characteristics

“…In recent years, MF foam has increasingly been used as acoustical materials, wipe products, thermal insulating layers, and even aircraft seats 19–21 . However, its wider applications in some fields of high requirements of high fire retardancy are still restrained by some disadvantages including relatively high heat release rate, rapid great mass loss over 350°C, and obvious volume shrinkages at high temperatures 22,23 . Consequently, it is of great significance to further improve its combustion performance.…”

“…[19][20][21] However, its wider applications in some fields of high requirements of high fire retardancy are still restrained by some disadvantages including relatively high heat release rate, rapid great mass loss over 350 C, and obvious volume shrinkages at high temperatures. 22,23 Consequently, it is of great significance to further improve its combustion performance. Regrettably, few related literature are up to now available.…”