Flammability of Polymer/Clay Aerogel Composites: An Overview

ABSTRACT

Polymer/clay aerogel composites fabricated using the freeze-drying method and water as solvent has drawn extensive attentions during the past decade. Such aerogels possess layered or network microstructures, low thermal conductivities, and good thermal stabilities; of special interest, they generally have very low flammability, which could be influenced by the composition and microstructure of the aerogel composites. The fire performance of the aerogels can be further improved with flame retardant modifications. Polymer/clay aerogel composites can also serve as effective flame retardant coatings. The mechanisms of the flame retardancy of polymer/clay aerogel composites are also discussed herein. The thorough survey of the current literatures offers useful information to realize potential of polymer/clay aerogels and help guidance to design novel high-performance polymer/clay aerogel composites.

KEYWORDS:

• polymer
• clay
• aerogel
• flammability
• flame retardancy

Abbreviations

AxCy	=	Alginate/clay aerogel containing x wt% alginate and y wt% clay compared with water when prepared;
FA20C5-2d	=	Poly (furfuryl alcohol)/clay aerogel containing 20 wt% Poly (furfuryl alcohol) and 5 wt% clay compared with water when prepared, and cued for 2 days;
FPU/Alag-20	=	Flexible polyurethane foam /Alumina aerogel composites (alumina sol with hydrolysis ratio of nAlIP/nH2O = 20/1 (mmol/mol)
PM9C1	=	Polyimide/clay aerogel containing 9 wt% polyimide and 1 wt% clay compared with water when prepared;
PxCy-z	=	PVOH/clay aerogel containing x wt% PVOH and y wt% clay compared with water when prepared, with gamma irradiation of z kGy;
PxCyFz	=	PVOH/clay aerogel containing x wt% PVOH, y wt% clay, and z wt% flame retardant PEPA compared with water;
P3-2C8-10	=	PVOH (Mw 31,000∼50,000)/clay aerogel containing 2 wt% PVOH and 8 wt% clay compared with water when prepared, with gamma irradiation of 10 kGy;
P8-2C8-10	=	PVOH (Mw 89, 0 00∼98, 000)/clay aerogel containing 2 wt% PVOH and 8 wt% clay compared with water when prepared, with gamma irradiation of 10 kGy;
P18-2C8-10	=	PVOH (Mw 146,000∼186,000)/clay aerogel containing 2 wt% PVOH and 8 wt% clay compared with water when prepared, with gamma irradiation of 10 kGy;
X2.5C2.5	=	Xanthan gum/ clay aerogel containing 2.5 wt% xanthan gum and 2.5 wt% clay compared with water when prepared;

Acknowledgments

This work was supported by the Science Challenge Project (TZ2018004) and National Science Foundation of China (51403192).

Additional information

Funding

Science Challenge Project. TZ2018004; National Natural Science Foundation of China, 51403192.