The main challenge in converting polymerized epoxidized plant oils (P-EPO) to high performance materials is the limitation of their short cross-link structures and brittle properties. Herein, a network (N-2) fabricated from a renewable material, dihydrocoumarin (DHC), demonstrated the potential to overcome substantially the brittleness of P-EPO material. The fused ring in DHC was successfully opened via a solvent-free chromium­(III) salen-mediated pathway, and a novel network, termed N-2, was created through an alternating copolymerization of DHC and diglycidyl ether epoxides. Repeating ether units in N-2 offered the capacity to sustain large deformation, and phenoxide end groups provided the reactivity to attack epoxides. Once a double network was built between N-2 and EPO derived network (N-1), a substantial performance improvement of P-EPO could be achieved. We targeted epoxidized soybean oil (ESO) as the model material, which showed a significant toughness enhancement (9-fold improvement in elongation at break combined with 85% tensile strength retention compared to the control P-ESO) after the introduction of N-2 network. Creep behaviors revealed the introduction of N-2 in P-ESO matrix lengthened the chains between cross-links, prolonged the response process and transferred the stress from N-1 segments to N-2 segments to retard P-ESO network fracture.

One kind of molecular glass material was prepared via the epoxidation of eugenol and a subsequent thermochemical conversion process. This biobased molecular glass (ET-eugenol) shows high potential in the design of self-healing materials while being incorporated into a polymeric matrix to form a multiphase system. Here, an ET-eugenol/polymerized soybean oil (p-ESO) system with a mass ratio of 1:2 was investigated. Results show that the scratch damage can be healed effectively at a temperature of 90 °C within 15 min or by ultraviolet radiation within seconds. Good dimension stability even at high temperatures can be kept in the whole healing process. A mechanical tensile test shows that compared to the neat p-ESO matrix the incorporation of ETeugenol (weight percent of 33%) led to a 2.7-fold increase in ultimate stress and a healing efficiency up to 88%. Gel permeation chromatography, nuclear magnetic resonance, and gas chromatography−mass spectrometer were carefully conducted to reveal the complex thermochemical reaction during the preparation process of ET-eugenol. Self-healing behaviors were characterized via atomic force microscope and optical images, and the corresponding healing mechanism was discussed from a multiphase structural viewpoint. The work reported here demonstrates the possibility of molecular glass as a promising candidate in the design of selfhealing materials.

A double-network strategy to toughen epoxy resin system is presented herein. Dihydrocoumarin (DHC), a hexatomic compound extracted from tonka bean, is used as the building block for the construction of the first network, and the diglycidyl ether of bisphenol A epoxy matrix is used as the second network. The resultant double network demonstrates a single glass transition and good compatibility between these two networks. Owing to the firm interfacial adhesion between networks and the effective stress transfer as well as external energy absorption derived from the DHC-based network, the double-network-based epoxy resin shows a significant toughness improvement without trade-offs in the tensile strength and elongation at break. The finding in this study provides a promising way to overcome the intrinsic brittleness of commercial epoxy resin via the utilization of renewable DHC for the construction of a novel double network.

As an important source of white pollution, disposable polystyrene fast food containers (DPSFFC) have attracted great attention, and the technologies for the effective reuse of DPSFFC are of great practical significance. Herein, an attempt was made to reuse DPSFFC to produce high-value microspheres for electronic devices. In the processing, DPSFFC were recycled as the matrix and biobased polyamide11 (PA11, derived from castor oil) was used as the dispersion phase to achieve a preferential location of TiO2 nanoparticles in the PA11 domains; taking advantage of the high solubility of recycled polysterene (RPS) in limonene, a biosolvent derived from citrus, PA11 microspheres encapsulated with TiO2 nanoshells (∼70 nm) were extracted from the recycled PS matrix successfully. The unique structure can be ascribed to a customized copolymer, composed of polystyrene and maleic anhydride segments (SMA-g-PS) via the RAFT (Reversible Addition–Fragmentation Chain Transfer Polymerization) strategy, introduced into the system. This copolymer acts as a compatibilizer and anchoring agent, significantly decreasing the number-average diameter of the microspheres. Impressively, the prepared microspheres demonstrate high potential as charged particles in electrophoretic imaging. This special property is highly related to the nanoshell/micron-core structure. Taking advantage of the disposable PS and bioresources, combined with scalable processing, an upcycling method was developed to produce high-value microspheres in a sustainable way.