Boron-zirconium-silicon ternary modified phenolic resin and preparation method thereof

The invention discloses a boron-zirconium-silicon ternary modified phenolic resin and a preparation method thereof. The boron-zirconium-silicon ternary modified phenolic resin comprises the following raw materials in parts by mass: 10-50 parts of phenol, 4-20 parts of formaldehyde, 1-15 parts of zirconium oxychloride, 1-15 parts of ethyl orthosilicate, 1-10 parts of boric acid, 2-10 parts of sodium hydroxide, 5-60 parts of ethanol, 5-15 parts of acetylacetone, and 1-10 parts of hydrogen peroxide; and the boron-zirconium-silicon ternary modified phenolic resin is prepared through multiple feeding, refluxing, stirring, pH value adjusting, discharging, solvent removing processes. The preparation method disclosed by the invention is simple and low in cost; a prepared modified resin is low in viscosity and low in toxicity, and can be used as an organic precursor for a dipping and cracking process for preparing ternary ceramic phase modified carbon/carbon composites, therefore, the modified resin has remarkable economic and social benefits.