Rosin-Based Epoxy Vitrimers with Dynamic Boronic Ester Bonds

Abstract

Rosin is an abundantly available natural product. In this paper, for the first time, a rosin derivative is employed as the main monomer for preparation of epoxy vitrimers to improve the mechanical properties of vitrimers. Novel epoxy vitrimer networks with dynamic reversible covalent boronic ester bonds are constructed by a reaction between thiols in 2,2′–(1,4–phenylene)–bis (4–mercaptan–1,3,2–dioxaborolane) (BDB) as a curing agent and epoxy groups in the rosin derivative. The rosin-based epoxy vitrimer networks are fully characterized by Fourier transform infrared spectroscopy (FTIR), an equilibrium swelling experiment, and dynamic mechanical analysis (DMA). The obtained rosin-based epoxy vitrimers possess superior thermostability and good mechanical properties. Due to transesterification of boronic ester bonds, rosin epoxy vitrimer network topologies can be altered, giving welding, recycle, self-healing, and shape memory abilities to the fabricated polymer. Besides, the effects of treating time and temperature on welding capability is investigated, and it is found that the welding efficiency of the 20% C-FPAE sample is >93% after treatment for 12 h at 160 °C. Moreover, through a hot press, the pulverized samples of 20% C-FPAE can be reshaped several times and most mechanical properties are restored after reprocessing at 200 °C for 60 min. Finally, chemical degradation is researched for the rosin-based epoxy vitrimers.

Fully Biobased Vitrimers: Future Direction toward Sustainable Cross‐Linked Polymers

“…[ 167 ] Up to date, two studies report the preparation of partially biobased vitrimers from fossil‐based 2,2’‐(1,4‐phenylene)‐bis[4‐mercaptan‐1,3,2‐dioxaborolane and a rosin‐based diepoxide or epoxidized soybean oil acrylate. [ 168,169 ] To the best of our knowledge, no study with higher renewable content was published.…”

“…Avérous and colleagues [ 159] Ad3 Am1 Catalyst-free −10 soybean oil acrylate. [168,169] To the best of our knowledge, no study with higher renewable content was published.…”

Rapid Stress Relaxation, Multistimuli-Responsive Elastomer Based on Dual-Dynamic Covalent Bonds and Aniline Trimer

“…When the relaxation times were applied in an Arrhenius plot, a linear relationship was observed as shown in Figure d, and the activation energy was calculated to be around 36 ± 1 kJ mol –1 . Interestingly, the calculated activation energy was lower than the reported activation energies of either solely used boronic esters − or imine bonds (38–157 kJ mol –1 ) − as the dynamic cross-links. It could be deduced that this combination of two DCBs (boronic esters, imine bonds) was much more efficient than the sole one in term of stress relaxation.…”

Biobased covalent adaptable networks: towards better sustainability of thermosets

“…180 Zeng et al reported rosin-based epoxy vitrimers with dynamic boronic ester bonds. 181 A rosin derivative–fumaropimaric acid (FPA) was synthesized via modifying rosin with fumaric acid and then reacted with epichlorohydrin to obtain a rosin-based epoxy monomer (FPAE). FPAE was cured with 2,2-(1,4-phenylene)-bis(4-mercaptan-1,3,2-dioxaborolane) (BDB) to fabricate an epoxy vitrimer via the reaction between thiols and epoxy groups (Fig.…”