Poly (m-phenylene isophthalamide)/graphene composite aerogels with enhanced compressive shape stability for thermal insulation

• Published in: Journal of sol-gel science and technology Vol. 96; no. 2; pp. 370 - 381
• Main Authors: Chen, Weiwang, Liu, Sha, Dong, Yutong, Zhou, Xiaomeng, Zhou, Fenglei
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.11.2020; Springer Nature B.V
• Subjects: Aerogels; Ceramics; Chemistry and Materials Science; Composites; Compressive strength; cryogels; etc.; Fire resistance; Glass; Graphene; Heat conductivity; Heat resistance; Heat transfer; High temperature; Inorganic Chemistry; Insulation; Materials Science; Morphology; Nanotechnology; Natural Materials; Optical and Electronic Materials; Original Paper: Nano- and macroporous materials (aerogels; Premixing; Stability; Thermal conductivity; Thermal insulation; Thermal resistance; Thermodynamic properties; xerogels; phenylene isophthalamide; Composite aerogels; Poly; Graphene; Compressive shape stability; Thermal insulation
• ISSN: 0928-0707; 1573-4846
• DOI: 10.1007/s10971-020-05396-8

To develop graphene-based composite aerogels with improved compressive shape stability that suitable for high-temperature applications, poly ( m -phenylene isophthalamide, PMIA) with excellent heat resistance and flame retardancy was used as the supporting material. The effects of PMIA content on aerogel morphology, structure, mechanical and thermal properties were discussed. Unlike other polymers, PMIA in the composite aerogels appeared as separate or stacked particles instead of interconnected framework or uniform coatings. Higher PMIA content tended to result in denser aerogels with smaller pores and thinner graphene sheet walls. The densified structure with plenty of PMIA particles incorporated was found to make the aerogel more rigid and less flexible. Their compressive strength therefore was greatly enhanced. Besides, it was also observed that the thermal conductivity of the prepared aerogels increased with the increase of PMIA content. Nevertheless, their thermal conductivity was still <0.045 W m −1  K −1 , indicative of considerable thermal insulation ability. Given that, the prepared composite aerogels with enhanced compressive shape stability may have a broad application prospect in thermal insulation. Highlights PMIA-reinforced graphene aerogels (PGAs) are successfully prepared by a premixing method. The resulted PGAs have smaller pores and thinner graphene walls with numerous PMIA particles incorporated. PGAs can support >2000 times its own weight, indicative of enhanced compressive strength. PGAs are good at thermal insulation with thermal conductivity values <0.045 W m −1 K −1 .