Water-soluble film having blend of PVOH polymers, and packets made therefrom

摘要

Disclosed are plasticized, water-soluble films having favorable cold-water solubility, wet handling, and thermoforming characteristics, and which can include a PVOH resin made up of blend of two or more PVOH polymers each having a monomodal molecular weight distribution, and the PVOH resin characterized by a viscosity in a range of about 13.5 cP to about 20 cP (or a corresponding weight average molecular weight), a degree of hydrolysis of about 84% to about 92%, a polydispersity index value in a range of about 1 to about 5, a residual water content of about 4 wt. % to about 10 wt. %, and a Resin Selection Index value in a range of 0.255 to 0.315; methods of making the films; compositions including PVOH resins for making the films; and pouch and packet articles made from the films.

主权项

1. A water-soluble film comprising:
at least 50 wt. % of a water-soluble polyvinyl alcohol (PVOH) resin that is a vinyl alcohol-vinyl acetate copolymer consisting of vinyl alcohol and vinyl acetate units, the PVOH resin having an average viscosity in a range of about 13.5 cP to about 20 cP, and a degree of hydrolysis in a range of about 84% to about 92%, the PVOH resin comprising a blend of first and second PVOH polymers that are vinyl-alcohol-vinyl acetate copolymers consisting of vinyl alcohol and vinyl acetate units, the first PVOH polymer having a viscosity in a range of about 8 cP to about 40 cP, the second PVOH polymer having a viscosity in a range of about 10 cP to about 40 cP, and the viscosity of the first PVOH polymer being less than the viscosity of the second PVOH polymer; and the film further having no more than 30 wt. % of a PVOH polymer having a viscosity less than about 11 cP.