Paper-based materials are highly
desirable as packaging
materials due to their numerous advantages that include low cost,
renewability, and biodegradability. However, their hydrophilicity
has limited their range of applications. Reported herein is a facile
and economical approach for the preparation of biodegradable water-resistant
paper for food-contact applications. Commercial printing paper and
cup papers are coated with melamine, which is FDA approved for food-contact
applications. Subsequently, a water-repellent outer layer is applied
using poly(dimethylsiloxane) (PDMS)–isocyanate. A relationship
between the PDMS concentration and water contact angles (WCAs) of
the obtained coating was studied. Typically, the coated cup paper
and printing paper had coating loadings of 1.61 ± 1.10 and 0.93
± 0.74 wt %, respectively. After the coatings had been applied,
the WCAs were very high (>125°), and water absorption had
decreased by 70% for printing paper and by 35% for cup paper. Considering
the facile fabrication method and the low-cost food-safe raw materials,
herein, this approach will have great potential for the large-scale
production of materials for use in food- and nonfood contact applications.