Extracting Eucommia ulmoides gum from Eucommia ulmoides Oliver and exploiting the residue as sustainable filler

The raw materials of Eucommia ulmoides Oliver (EUO) were efficiently-pretreated by ionic liquid (IL)-assisted mechanical mixing to break down the plant cell wall and expose the Eucommia ulmoides gum (EUG), thereby facilitating the extraction of EUG. The effects of IL loading, temperature, and the duration of mechanical mixing on the yield of EUG were investigated. Considering the extraction yield and molecular weight of EUG, the pretreatment conditions including the mass ratio of EUO to IL, the mixing temperature and time, and other chemical additives were optimized. Following the epoxidation of the extracted low-molecular-weight EUG, the modified EUG showed strong adhesion and had potential as a renewable crosslinking agent. Furthermore, the plant residue was used as a sustainable filler for EUG processing to realize the effective utilization of Eucommia ulmoides resource. Therefore, this work established a practical strategy for extracting EUG and exploiting high-value utilization of the residue.