All-biomass rubber leaf trays enabled by lignin-based self-adhesion during hot-pressing: A sustainable alternative to plastics.

Abstract

The widespread use of plastic products in the catering industry brought potential risks to human health, and it became urgent need for the development and exploration of alternative materials. Rubber leaves are a renewable, biodegradable natural eco-friendly material containing biomass components such as lignin, cellulose, and hemicellulose that facilitate self-adhesion. By adding rubber leaf powder between the rubber leaf layers, this study proposes a feasible method for fabricating all rubber leaf trays through hot-pressing with no use of adhesives. By comparing the physical properties, mechanical properties, and water resistance, we successfully developed rubber leaf trays with excellent mechanical properties and high environmental performance when the preparation parameters were a powder addition ratio of 17%, powder size of 40-60 mesh, and moisture content of 30%. They can mostly degrade in about 140 days, whereas plastic takes decades or even over a hundred years. Moreover, by using intact rubber leaves as the surface layer, this method significantly reduces the risk of fine particle migration compared to products entirely molded from powder. This study not only provides a substitute for traditional plastic trays but also opens a new avenue for the high-value utilization of rubber leaf waste.