Foam type water-soluble packaging film and preparation method thereof

The invention relates to the technical field of packaging, in particular to a foam type water-soluble packaging film and a preparation method thereof. The water-soluble foam comprises a water-soluble matrix and bubbles uniformly distributed in the water-soluble matrix, the diameter of the bubbles is smaller than the thickness of the water-soluble packaging film; the volume of the bubbles accounts for 5-80% of the total volume of the water-soluble matrix; the raw material of the water-soluble matrix comprises polyvinyl alcohol. The water solubility and mechanical properties of the water-soluble packaging film are effectively improved through the water-soluble matrix components, the proportion and the bubble content, the transverse tensile strength and the longitudinal tensile strength of the water-soluble packaging film are both not lower than 11 MPa and even can exceed 12.5 MPa, the transverse tensile elongation and the longitudinal tensile elongation can both exceed 55%, and the water-soluble packaging film