Composite filter material and preparation method thereof

The invention discloses a composite filter material, a preparation method thereof and a filter material, the composite filter material is a multi-layer composite membrane, the multi-layer composite membrane at least comprises a base material and a hydrophilic modified PTFE porous material compounded on the base material, the hydrophilic modified PTFE porous material is obtained by taking a porous PTFE membrane as a main body and sequentially carrying out dopamine modification and PVA modification, and dopamine modification is carried out to obtain a first modified membrane. The film product provided by the invention has good structural performance, effectively overcomes the defect of poor binding property of the PTFE film, and realizes the product with stable structure and washing resistance. 本发明公开了复合滤材及其制备方法，滤材，其为多层复合膜，至少包括基材以及复合到基材上的亲水改性PTFE多孔材料，其中亲水改性PTFE多孔材料为以多孔PTFE膜为主体，并先后经过多巴胺改性和PVA改性得到，其中多巴胺改性得到第一改性膜。本发明的膜产品结构性能好，有效克服了PTFE薄膜结合性差的不足，实现了结构稳固、耐清洗的产品。