Lignin-containing biodegradable UV-blocking films: a review

Due to the severe waste plastics pollution issues, fabricating biodegradable films as substitutes for plastic has been a pursuit of modern scientists for the past few years. UV (ultraviolet) shielding is essential for the application of biodegradable films in packaging materials, agricultural mulch, plastic greenhouses, and window films. Identified as a natural UV-absorber, lignin can be a safe additive to biodegradable film, endowing the film with urgently needed UV-resistance properties while ensuring the overall sustainability of the films. The present paper comprehensively reviews the research status on the preparation and application of lignin-containing biodegradable UV-blocking films. Additionally, the effect of lignin on the mechanical and optical properties of films is revealed. In general, this review provides some theoretical guidance for manufacturing lignin-containing biodegradable UV-blocking films with outstanding mechanical properties and optical transmittance, thus broadening their application in packaging, agriculture, and green building materials. The present paper comprehensively reviews the research status on the preparation and application of lignin-containing biodegradable UV-blocking films, and the effect of lignin on the mechanical and optical properties of films.