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Novel bio-based acrylate was designed through the epoxy ring-opening reaction of cardanol glycidyl ether (CGE) with fatty acids from camelina oil (FACO), followed by epoxidation of unsaturated chains and then acrylation of the epoxides. Cardanol- and camelina oil-based acrylates were also respectively synthesized for comparison purposes. The bio-based acrylate coatings were then produced under UV-radiation from the acrylates monomers with an addition of a photoinitiator. Polymerization of the acrylates and synthesis of the monomers were observed using Fourier transform infrared (FTIR) spectroscopy, and the chemical structures and acryl contents of the acrylates were confirmed by proton nuclear magnetic resonance (1H NMR). The mechanical and thermal properties of the cured acrylates were evaluated using tensile test, dynamic mechanical analysis (DMA), and thermogravimetric analysis (TGA). Observation of resistances to water, solvent, and hydrolytic degradation were conducted to water and toluene uptake test, methyl ethyl ketone (MEK) rub test, and a degradation test under sodium hydroxide solution. Gel content was measured to evaluate performance of the coatings, and other coating performances including gloss, adhesion, and pencil hardness were determined using the wood panel coated with the cured acrylates. Compared to acrylated epoxidized soybean oil (AESO) coating, the acrylate derived from the cardanol modified fatty acids showed higher tensile strength, hardness, glass transition temperature, thermal decomposition temperature at maximum degradation rate, and resistances to solvent and hydrolytic condition of the cured coating. Therefore, the newly designed acrylate is a great alternative to AESO.

Conventional thermoset materials cannot be remolded and recycled due to the covalent bonds existing in the network. The reversible nature of secondary interactions between monomeric units renders supramolecular structure reconfigurable abilities upon exposure to appropriate stimuli. This feature is quite useful in the design of novel thermoset materials with remoldability and recyclability, but its widespread adoption is limited due to the low strength and high cost of supramolecular structure. Here, we present a new class of thermoset with a distinct recycling mechanism and structural design. It is strong, transparent, recyclable, 100% biorenewable, creep resistance after thermal treatment, and produced in a ultrafast, scalable and cost-effective manner. These characteristics come from a purpose-designed hybrid network via a ultraviolet radiation in seconds. This technology provides a new way to obtain thermosets with remoldability and recyclability. It is green and efficient, not limited in lab, and can be scaled up for industry.

Plant oils are attractive renewable feedstocks for biobased pressure-sensitive adhesives (PSAs). In this study, we investigated how the PSA adhesion properties were influenced by the compositions comprised of epoxidized soybean oil (ESO), 3,4-epoxycyclohexylmethyl 3,4-epoxycyclohexanecarboxylate (ECHM), dihydroxyl soybean oil (DSO), rosin ester, and cationic photo initiator. When the amounts of ESO and photo-initiator were constant, the variables of ECHM, DSO, and rosin amounts and their interactions were significant in influencing PSA peel adhesion strength, with p values smaller than 0.05 under a 95% significance level. Rosin amounts with the largest coefficient of 0.94 compared to the other variables are the most determinant factors. The peel adhesion strength was higher when using relatively a lower level of ECHM and a higher level of ESO and rosin. A model with the coefficient of determination (R2) of 95.06% was obtained to describe the relationship between the amount of resin constituents (ECHM, DSO, and rosin) and PSA peel adhesion strength in the experimental variable ranges. The optimal PSA formulation without cohesive failure was (ECHM = 0.04, DSO = 0.7, rosin = 0.7), resulting in a peel adhesion strength of 4.45 N/in. Structure–property relationships of the PSAs were established via thermal and rheological studies.

Plant oil is one of the world’s most abundant renewable resources; however, its derived epoxies are low in thermal resistance and mechanical strength. In this work, a new chemical route referred to “competitive nucleophilic attack (CNA)” was discovered to achieve plant-oil-based epoxy with high thermal resistance and mechanical strength as well as many other unique properties comparable to those of diglycidyl ether of bisphenol A (DGEBA), one of the most popular petroleum-based epoxies. The CNA route was realized by using 10-undecenoic acid (UA), a plant-derived monomer, as a building block reacting with alicyclic oxirane chemicals, such as 4-ethenyl-7-oxabicyclo[4.1.0]heptanes (ECP), to achieve epoxy monomers with ether-bridged cycloaliphatic ring structure. A newly formed hydroxyl (NFH) is involved in the nucleophilic attack upon oxonium to compete with UA anion during the UA–ECP reaction. The resultant epoxy is UV-curable in a few seconds, possessing high tensile strength (∼48 MPa), high glass transiti...

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 ...