Biomass carboxylic acid modified hydrotalcites for improving the mechanical strength and recyclability of 100 % biobased carbon content epoxy soybean oil based vitrimers

To realize the demand of sustainable development in materials industry, vitrimers deriving from epoxidized soybean oil (ESO) have received considerable attention because of their environmentally friendly and renewable. However, they suffer from poor mechanical strength and non-reprocessability, which confine their application. Herein, a facile design of 100 % bio-based carbon contents vitrimers incorporating ESO and citric acid modified layered double hydroxides (CA-LDHs) was proposed, which showing good mechanical properties and accelerated stress relaxation. Optimal performances of vitrimers with best tensile strength, curing and repairing efficiency were obtained at 20 wt% CA-LDHs loading. The tensile strength of 20EC-CLE increased by 233 % compared with pure EC-E due to the reinforcing effect of CA-LDHs and the increased cross-linking density. Benefit from the abundant Al3+ catalytic sites and large contact areas of the CA-LDHs lamella, the vitrimers showed an excellent curing and 82 % reprocessing efficiency. Interestingly, the precursor of the vitrimers was used as an adhesive layer for polyvinyl chloride (PVC) leather and provided 3.4 +/- 0.4 N/cm peel strength and bonding reproducibility.