The invention discloses a preparation method of a nano-silica / hydroxysilane
coupling agent composite modified
polyurethane super-hydrophobic membrane. The nano-silica / hydroxysilane
coupling agent composite modified
polyurethane super-hydrophobic membrane is prepared from the following main raw materials:
polyol,
isocyanate, a catalyst, a hydrophilic chain
extender, a neutralizer, a micromolecule chain
extender, a
silane coupling agent, nano-silica, deionized water and a post-chain
extender. According to the invention, a synthesized
polyurethane system is modified by introducing
nano silicon dioxide particles modified by a hydroxyl
silane coupling agent. A hydroxyl group of the hydroxyl
silane coupling agent can chemically react with an
isocyanate group of a waterborne polyurethane
system, and silane is introduced to modify the hydrophobicity of the
polyurethane membrane from the chemical aspect. The hydrophobicity of the
polyurethane membrane is modified from the physical aspect by a micro-nano structure formed after the membrane is formed by the
nano silicon dioxide particles treated by the hydroxyl
silane coupling agent. The
water contact angle of the prepared polyurethane super-hydrophobic membrane can reach 145-155 degrees, the
rolling angle is 5-7 degrees, and the application field of the
polyurethane membrane is widened.