Starch and Zein Biopolymers as a Sustainable Replacement for PFAS, Silicone Oil, and Plastic-Coated Paper

Paper is envisioned as an alternative to plastics in certain applications to overcome the problems associated with the excessive use of plastics. Water and oil repellency is one of the key requirements for many packaging applications. However, the existing water and oil repellent paper products have poor biodegradability and are also difficult to recycle. Here we have reported an inexpensive approach for preparing recyclable water and oil repellent paper products using biobased materials such as starch and zein. The application of dual-layer coatings of starch and zein onto a Kraft paper yielded a “Cobb 60” value of 4.81 g/m2. In addition, the coated paper exhibited excellent grease resistance with a kit rating of 12/12. Scanning electron microscopy characterization confirmed that the dual-layer coating filled the pores of the paper substrate. The mechanical properties, as well as the thermal stability of the paper, were maintained after the coating treatments, and thus this coated paper has potential for widespread use in our daily lives while also minimizing the environmental footprint of packaging materials.