High fire retardation phenol formaldehyde foam preparation method

The present invention discloses a high fire retardation phenol formaldehyde foam preparation method, which is characterized in that the preparation method comprises the following steps: (1) preparing a foamable phenol formaldehyde resin: mixing formaldehyde and phenol, adding NaOH or KOH as a catalyst, carrying out a reaction for 1 h at a temperature of 70 DEG C, then carrying out the reaction for 2 h at a temperature of 80 DEG C, adding boric acid to adjust the reaction liquid, and carrying out vacuum dehydration to obtain the foamable phenol formaldehyde resin with a viscosity of 3000-5000 mPa.s; (2) selecting the foamable phenol formaldehyde resin, a curing agent, a surfactant and a filler according to a mass ratio; and (3) injecting the materials into a reaction container, uniformly stirring, foaming, cooling, and discharging from the mold. According to the high fire retardation phenol formaldehyde foam preparation method, according to GB8624-2006, a detected oxygen index is more than 44%, and is increased compared with the traditional phenol formaldehyde foam oxygen index (more than or equal to 38%), and a fire prevention performance can be significantly improved.