Water-resistant kraft paper with different content of starch coated lightweight packaging application

Paper packaging such as boxes, corrugated cardboard, have the disadvantage of being difficult to water resistance. The water resistance coating can effectively make up for this shortcoming. At the same time, starch-based modified starch coating is also one of the solutions to achieve water resistance goals. However, different types of starch coating have slightly different water resistance capabilities. This article aims to study the effects of different starch-based modified starch coating and coating thickness on water resistance capabilities. Modified starch is made from corn, wheat, potato, and cationic starch mixed with polyvinyl alcohol and then sprayed on kraft paper. The physical and mechanical properties, air permeability, and contact angle are tested in accordance with TAPPI and ISO standard. The 3-layer cationic modified starch coating achieves minimum air permeability, and the mechanical properties are also significantly improved, but the contact angle is not much different from other samples. In summary, the film-forming ability and low air permeability of cationic modified starch have the potential for high water resistance performance