Enhancing Barrier Properties of Cellulose Paper: A Rosin-Based Polymer Coating Approach

The widespread use of plastics has caused serious environmental pollution, and the use of cellulose paper products to replace plastics has attracted worldwide attention. However, the rich hydroxyl groups and structure voids lead to poor barrier properties of cellulose paper products to water and oil. Herein, a rosin-based polymer coating (RB) is reported, which is prepared by cross-linking a rosin-modified silane coupling agent (RM) with hydroxyl-capped polydimethylsiloxane (OH-PDMS) and ethyl orthosilicate (TEOS). The RB can form a dense and uniform barrier layer on the surface of the cellulose paper product, so that the RB-coated paper (RB paper) exhibits excellent properties, including (1) water resistance (exhibiting a water contact angle of 102.3°, the relative water absorption rate decreased by over 90% at both 25 and 90 °C, reaching 35.1% and 45.9%, respectively), (2) oil resistance (Kit test reaches no. 10, and the relative oil absorption rate decreased by over 90% at both 25 and 90 °C, reaching 4.1% and 6.4%, respectively), and (3) high mechanical properties (tensile strength increased from 23.2 to 40.6 MPa, stronger than partly commercial plastics). Moreover, RB paper exhibits biodegradability and recyclability. These impressive performances position RB paper as a viable alternative to plastic.