Heat release and structural collapse of flexible polyurethane foam
详细信息 查看全文
- 作者：R.H. Krä ; mer ; M. Zammarano ; G.T. Linteris ; U.W. Gedde ; J.W. Gilman
- 关键词：Polyurethane ; Flexible ; Foam ; Heat release ; Melt dripping ; Combustion
- 刊名：Polymer Degradation and Stability
- 出版年：2010
- 出版时间：June 2010
- 年：2010
- 卷：95
- 期：6
- 页码：1115-1122
- 全文大小：856 K
文摘
Flexible polyurethane foam used in upholstered furniture remains one of the major fire hazards to date. The heat release rate of burning items made of foam depends strongly on the foam's physical behavior, notably its collapse to a burning liquid that can result in a pool fire. In this contribution, the cone calorimeter was used to study the physical processes and to determine their influence on foam combustion over a range of external heat fluxes. The initial stage of foam collapse can be described as the propagation of a liquid pyrolysis layer through the foam sample. The rate of propagation of the liquid layer was found to depend strongly on the convective heat transfer from the flame, which simultaneously defined and depended on the sample shape. The effective heat of combustion during foam collapse and pool fire was matched to the heat release potential of the components of the foam formulation to deduce which are consumed. The proposed analysis can serve to clarify the mechanism of flame retardant action, as demonstrated for a commercial brominated-phosphorous compound.