The invention discloses a preparation method of a sandwich plate, and belongs to the technical field of decorative material preparation. According to the preparation method, firstly, camphorwood is used as a
raw material, and the camphorwood has the effects of
insect prevention,
mildew prevention and sterilization, so that the insulation property of an internal plate is greatly increased; then
peanut oil is used a
raw material, and micro-blasting wood pulp and the
peanut oil are mixed and fermented, so that the internal plate of the preparation method has the effects of
moisture protection, sterilization and bacteriostasis;
zinc powder is soaked in a
lanthanum nitrate solution, so that a
lanthanum oxide protective film is formed on the surface of the
zinc powder, the relative contact angleof the
zinc powder is increased by the
lanthanum oxide protective film, and the
fire resistance of the zinc powder is good, so that an external plate has excellent
flame resistance due to the use ofthe zinc powder; then sardines bones are used as raw materials, the sardines bones contain a large amount of
fluorine, the
fluorine has hydrophobicity, so that the
moisture resistance of the modifiedzinc powder is increased, the modified zinc powder is used as the
raw material to prepare the external plate, and two modified external plates are respectively bonded to the front and back surfaces ofthe modified internal plate by
epoxy glue so as to prepare the sandwich plate. The preparation method has wide application prospects.