title: Highly Efficient Flame Retardant Polyurethane Foam with Alginate/Clay Aerogel Coating.
abstract: Highly efficient flame retardant polyurethane foams with alginate/clay aerogel coatings were fabricated using a freeze-drying method. The microstructure and the interaction of the samples were characterized with scanning electron and optical microscopy (SEM) and (OM). The results show that PU foam has a porous structure with pore sizes of several hundred microns, and that of aerogel ranges from 10 to 30 μm. The PU foam matrix and the aerogel coatings have strong interactions, due to the infusion of aerogel into the porous structure of the foam and the tension generated during the freeze-drying process. Both the PU foam and the aerogel exhibit good thermal stabilities, with onset decomposition temperatures above 240 °C. Combustion parameters, including LOI, TTI, HRR, TSR, FIGRA, CO, and CO2, all indicate significantly reduced fire risk. Total heat release of all but one of the samples was maintained, indicating that the flame retardant mechanism is to decrease flame spread rate by forming a heat, oxygen, and smoke barrier, rather than by reducing fuel content. This facile and inexpensive post-treatment of PU foam could expand its fire safe applications.
authors.affiliation: Institute of Nuclear Physics and Chemistry, China Academy of Engineering Physics , Mianyang 621000, China.
authors.forename: Hong-Bing
authors.initials: HB
authors.lastname: Chen
authors.affiliation: Institute of Nuclear Physics and Chemistry, China Academy of Engineering Physics , Mianyang 621000, China.
authors.forename: Peng
authors.initials: P
authors.lastname: Shen
authors.affiliation: School of Science (Sichuan), Xihua University , Chengdu 610039, China.
authors.forename: Ming-Jun
authors.initials: MJ
authors.lastname: Chen
authors.affiliation: Research Center of Laser Fusion, China Academy of Engineering Physics , Mianyang 621000, China.
authors.forename: Hai-Bo
authors.initials: HB
authors.lastname: Zhao
authors.affiliation: Department of Macromolecular Science and Engineering, Case Western Reserve University , Cleveland, Ohio 44106-7202, United States.
authors.forename: David A
authors.initials: DA
authors.lastname: Schiraldi
keywords: aerogel; alginate; coatings; flame retardant; polyurethane