Fabrication of superhydrophobic and degradable cellulose paper materials for straw application

Cellulose-based materials are considered to be green and sustainable substitutes for plastics. However, their hydrophilicity and water instability limit further applications. Herein, ethyl cellulose (EC) and hydrophobic SiO2 nanoparticles (NPs) were employed to prepare hydrophobic SiO2@EC/P materials by dipping-spraying method. A series of cellulosic papers with various hydrophobicity (water contact angle (WCA) from about 90° to 166°, and contact angle hysteresis (CAH) less than 5°) were fabricated by varying the amount of SiO2 NPs. The dry and wet strength of the modified paper increased by 72.3% and 916.7%, respectively. Soaking test shows that the SiO2@EC/P straws remain intact after being placed in different beverages and water at the temperature of 0 to 90 °C for 2 h. Furthermore, these straws can be completely degraded after being buried into the soil for 200 days. Therefore, SiO2@EC/P materials are promising alternative materials for plastic straws. The potential application of SiO2@EC/P materials would effectively alleviate the ‘white pollution’ problem.Graphical abstract