Epoxidized plant oil (EPO) thermosets usually exhibit poor performance due to the short, brittle, and amorphous cross-link structures. To fabricate fully biobased high performance EPO thermoset, we synthesized dicarboxyl-terminated polyamide1010 (NYL) oligomers from castor oil derived monomers, i.e., sebacic acid and decamethylene diamine, and used the NYL to cure epoxidized soybean oil (ESO) to fabricate all plant oil derived epoxy thermoset through a catalyst-free curing method. Chemorheological study indicated that the curing rate decreases with increasing NYL chain length. The cross-link density of the epoxy thermoset decreases while the crystallization enhances with increasing NYL chain length, which results in drastic enhancement in tensile strength, Young's modulus, and elongation at break of the resultant thermosets, enabling those parameters to enhance by up to 59, 145, and 18 times, respectively, compared to sebacic acid cured ESO thermoset. The melting temperature and thus the heat resistance of the thermosets are also enhanced obviously with increasing NYL chain length. In addition, the thermosets show good durability and excellent thermal stability. With excellent comprehensive properties, the all plant oil derived epoxy thermosets could find some structural applications other than adhesive and coating.

Conventional superhydrophobic materials for oil/water separation were usually prepared from nondegradable and nonrenewable resources, which would not only increase resource crisis but also cause environmental pollution after discarding. In this study, we report a renewable and biodegradable superhydrophobic material, which was fabricated via a two-step curing dipcoating method and was composed of cellulosic filter paper or fabric, cured epoxidized soybean oil (CESO), ZnO, and stearic acid (STA) as the substrate, adhesive, rough structure, and low energy modifier, respectively. The CESO combined ZnO nanoparticles with cellulosic substrate tightly to show excellent stability when suffering from immersing in water and oil for 7 days without losing superhydrophobicity. When the superhydrophobic coating was constructed onto the surface of cellulosic fabric, the material showed high separation efficiency with the values higher than 97% during separation of various oil/water mixtures. The sustainable and biodegradable superhydrophobic material may find potential application in efficient oil/water separation without creating material waste after throwing away.

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Sustainable polyurethanes prepared from castor oil and diisocyanates show very low strength and toughness, due to the highly cross-linked and flexible structure. Herein, we report a new strategy to simultaneously reinforce and toughen castor oil-based polyurethane via incorporating a stiff component (isosorbide, IS) to enhance network stiffness and reduce crosslink density. The crosslinking degree decreases while the strength, moduli, ductility and heat resistance significantly increase accordingly with increasing IS content. The tensile behaviors are tunable over a broad range (either as elastomers or as plastics) depending on the compositions. The polyurethanes show excellent thermal stability with onset decomposition temperature higher than 280°C. The investigation provides a new hint for future design and fabrication of high performance sustainable polymers from other vegetable oils.

Inherent brittleness and low heat resistance are the two major obstacles that hinder the wide applications of poly(L-lactide) (PLLA). In this study, we report a fully biobased, highly toughened and heat-resistant PLLA ternary blend, which was prepared by dynamic vulcanization of PLLA with poly(D-lactide) (PDLA) and an unsaturated bioelastomer (UBE). The results indicated that during dynamic vulcanization PDLA cocrystallized with PLLA to form stereocomplex (SC) crystallites, which not only enhanced the molecular entanglement but also accelerated the crystallization rate of PLLA matrix. With increase in the content of PDLA, the matrix molecular entanglement increased while phase-separation was enhanced, which enabled the impact strength to increase first and then decrease. The ternary blends containing 10 wt.% PDLA showed the highest impact strength. The presence of SC crystallites makes it possible to achieve a fully sustainable PLLA/VUB/PDLA ternary blend with highly crystalline matrix under conventional injection molding, due to the high nucleation efficiency of SC towards crystallization of PLLA. The highly crystalline ternary blend showed excellent heat resistance and better impact toughness than high impact polystyrene.