| Several different ways of achieving fire retardancy in flakeboards were investigated: application of the fire retardant as a powder while forming the board; full-cell pressure impregnation of solutions of fire retardants; gas injection of the fire retardants in a one step process; and incorporation of the fire retardant by modification of a phenolic resin.;The strength properties considered were shear strength, internal bond strength (IB), modulus of elasticity (MOE), modulus of rupture (MOR) and Heat Release Rate (HRR). The fire retardants reduced the strength properties of the flakeboards. The way the fire retardants were applied was also important, with full cell the most efficient method, followed by resin, gas injection of the fire retardants, the boron phenolic modified and powder application.;The fire retardant chemicals used were borax, boric acid, Timbor;The two press processes used (conventional) and steam injection press (SIP) showed almost no differences for HRR. SIP was more significant as an improvement for boards preparation than a way to improve fire retardancy properties.;The adhesive resins used were a phenolic resin, an isocyanate based resin, and a phenolic modified resin with incorporation of boron. The fire retardancy was not significantly affected by the resin, except for the boron modified resin, where no additional fire retardant chemical was applied to the board. The isocyanate resin gave the strongest boards in most of the cases. Boron modified phenolic resin did not improve the fire retardancy, but board DPF, phenolic resin and SIP. Others chemicals, such as Timbor... |
