Flame Retardation of Polyurethane Foams Modified with Expandable Graphite and Aluminum Hydroxide

Expandable graphite (EG) and aluminum hydroxide (ATH) were incorporated into rigid polyurethane foam (RPUF) to prepare single-modified RPUF by EG and ATH respectively,and compound-modified RPUF by EG and ATH.Oxygen index and flame retardation of the RPUFs were studied.The results indicate that the synergistic flame retardant effect was significant when EG and ATH was used in combination,and the oxygen index of the EG15/ATH15 compound-modified RPUF up to 31%.Compared with the RPUF before modification,heat release rate peak of the EG15/ATH15 compound-modified RPUF decreased from 148.8 kW·m-2 to 66.1 kW·m-2,smoke release rate peak reduced from 0.106 m2·s-1 to 0.047 m2·s-1.Flame ratardant efficiency of compound-modified RPUF was better than that of single-modified RPUF.