Fiber-reinforced pure inorganic flame retardant foam composite and preparation method thereof

The invention belongs to the technical field of composite preparation, and relates to a method for preparing a fiber-reinforced pure inorganic flame retardant foam composite. A glass fiber mat, a basalt fiber mat, an aluminum silicate fiber mat, an alumina fiber mat or a mullite fiber mat is used as a reinforcement, inorganic sol or solution, such as silica sol, alumina sol, water glass or an aluminum dihydrogen phosphate solution is used as an impregnating agent, and a microcapsule foaming method is used to prepare a low-density pure inorganic flame retardant foam composite plate. The method avoids the defects that the fiber content is low, the fiber dispersion is uneven, and the mechanical properties resulting therefrom are poor; the fiber in the composite is uniformly arranged, and the fiber mass content can reach 40-60%; the composite is good in mechanical property and formability; the density of the foam composite can be flexibly adjusted through adjusting the proportion of a microcapsule inflating agent added; the combustion level can reach the DIN5510 S5 grade.