title: Formation of layer-by-layer assembled titanate nanotubes filled coating on flexible polyurethane foam with improved flame retardant and smoke suppression properties.
abstract: A fire blocking coating made from chitosan, titanate nanotubes and alginate was deposited on a flexible polyurethane (FPU) foam surface by a layer-by-layer assembly technique in an effort to reduce its flammability. First, titanate nanotubes were prepared by a hydrothermal method. And then the coating growth was carried out by alternately submerging FPU foams into chitosan solution, titanate nanotubes suspension and alginate solution. The mass gain of coating on the surface of FPU foams showed dependency on the concentration of titanate nanotubes suspension and the trilayers's number. Scanning electron microscopy indicated that titanate nanotubes were distributed well on the entire surface of FPU foam and showed a randomly oriented and entangled network structure. The cone calorimeter result indicated that the coated FPU foams showed reduction in the peak heat release rate (peak HRR), peak smoke production rate (peak SPR), total smoke release (TSR) and peak carbon monoxide (CO) production compared with those of the control FPU foam. Especially for the FPU foam with only 5.65 wt % mass gain, great reduction in peak HRR (70.2%), peak SPR (62.8%), TSR (40.9%) and peak CO production (63.5%) could be observed. Such a significant improvement in flame retardancy and the smoke suppression property for FPU foam could be attributed to the protective effect of titanate nanotubes network structure formed, including insulating barrier effect and adsorption effect.
authors.affiliation: State Key Laboratory of Fire Science, University of Science and Technology of China , 96 Jinzhai Road, Hefei, Anhui 230026, People's Republic of China.
authors.forename: Haifeng
authors.initials: H
authors.lastname: Pan
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.forename: Ying
authors.initials: Y
authors.lastname: Pan
authors.forename: Lei
authors.initials: L
authors.lastname: Song
authors.forename: Yuan
authors.initials: Y
authors.lastname: Hu
authors.forename: Kim Meow
authors.initials: KM
authors.lastname: Liew
keywords: adsorption effect; flame retardancy; insulating barrier effect; layer-by-layer assembled method; smoke suppression; titanate nanotubes