Nano TiO2-doped anti-ultraviolet para-aramid nano paper and preparation method thereof

A preparation method of nano TiO2-doped anti-ultraviolet para-aramid nano paper, comprising the following steps:

• step 1:
• mixing γ-aminopropyltriethoxy silane, anhydrous ethanol and water, stirring and adjusting the pH value to 3-5, thereby obtaining a γ-aminopropyltriethoxy silane solution;
• mixing nano TiO2, water and anhydrous ethanol and ultrasonically dispersing to obtain a nano TiO2 dispersion;
• mixing the nano TiO2 dispersion with the γ-aminopropyltriethoxy silane solution, stirring, and centrifuging to obtain a first centrifuged product;
• re-dispersing the first centrifuged product into a mixed solution of water and anhydrous ethanol, and centrifuging again;
• and
• repeatedly dispersing the centrifuged product into a mixed solution of water and anhydrous ethanol and centrifuging, repeating the above steps, and drying the final centrifuged product to obtain a powdery modified nano TiO2;
• step 2:
• mixing dimethyl sulfoxide, para-aramid fibrid and KOH to obtain mixed solution A, stirring the mixed solution A at room temperature until the color of the mixed solution A is changed to dark red, so as to obtain a para-aramid fibrid suspension;
• and
• step 3:
• adding water to the para-aramid fibrid suspension and defibering to obtain a defibered para-aramid fibrid suspension;
• ultrasonically dispersing the powdery modified nano TiO2 in water to obtain an ultrasonically dispersed nano TiO2 solution;
• mixing the ultrasonically dispersed nano TiO2 solution with the defibered para-aramid fibrid suspension, and stirring to obtain mixed solution B, wherein a mass concentration of nano TiO2 in the mixed solution B is 2%˜10%;
• carrying out a suction filtration, squeezing and drying on the mixed solution B to obtain the nano TiO2-doped anti-ultraviolet para-aramid nano paper.