Development and Mechanism of High-Performance Fully Biobased Shape Memory Benzoxazine Resins with a Green Strategy

Abstract

Developing high-performance fully biobased shape memory thermosets with a green strategy is a challenging topic of great interest. Herein, two unique fully biobased benzoxazine resins with excellent shape memory properties, denoted as poly­(IE-dea) and poly­(G-dea), were developed by synthesizing two fully biobased benzoxazine monomers (IE-dea and G-dea) using a solvent-free method. The thermal, mechanical, and shape memory properties of poly­(IE-dea) and poly­(G-dea) were studied. Among the fully biobased shape memory polymers reported so far, poly­(IE-dea) and poly­(G-dea) have the highest glass transition temperatures (138 and 216 °C), initial thermal decomposition temperatures (340 and 347 °C), and tensile strengths (85.1 ± 2.5 and 65.9 ± 2.7 MPa). In addition, poly­(IE-dea) and poly­(G-dea) exhibit excellent shape memory properties. After four shape memory cycles, their shape fixity ratios are 97.7–98.0% and 96.7–97.2%, respectively, and their shape recovery ratios are 96.7–97.2% and 93.0–93.4%. In fact, they are the first two fully neat biobased shape memory benzoxazine resins up-to-date. The mechanism behind the excellent integrated performances of poly­(IE-dea) and poly­(G-dea) results from unique integrated actions of the flexible decane segment and rigid cross-linked structure from the polymerization of oxazine rings.

Review on the Accelerated and Low-Temperature Polymerization of Benzoxazine Resins: Addition Polymerizable Sustainable Polymers

“…A copolymerization of double bonds with oxazine is proposed as shown in Figure 17c [95]. Similarly, involvement of propenyl group in the crosslinking reactions was also noticed by Sha et al [207].…”

The chemical effect of furfuryl amide on the enhanced performance of the diphenolic acid derived bio‐polybenzoxazine resin

“…All of the amide-containing polybenzoxazines possess excellent performance, and both the T g and T d10 values of poly(DFA-fa) are higher than that of almost all of the highperformance di-oxazine bio-benzoxazine resins recently reported. 23,25,48,[52][53][54][55][56] The results show that our amidation strategy not only can completely solve the problem of poor thermal stability of the DPA-derived benzoxazine resins, but it also allows obtaining excellent properties when amidation is carried out with furfurylamine.…”

Recent development on bio‐based thermosetting resins

“…Due to the cross-linking reaction involving double bonds in isoeugenol-based benzoxazine, at the same time, the integration of flexible long chains and rigid groups also endows the resins with shape memory property. 165 Combined with the Schiff base reaction between aldehyde group and polyether amine 166 or copolymerization with epoxidized vegetable oil, 167 vanillinbased shape memory resins were developed as well. Moreover, with the assistant of Schiff base reaction, Ishida et al 168 designed a bio-resourced benzoxazine with long chain ethers, which was successfully applied in surfactant agent.…”

“…For example, in Gu's group, guaiacol and isoeugenol were reacted with long chain diamine (1,10‐diaminodecane) under solvent‐free conditions to obtain two kinds of difunctional benzoxazine. Due to the cross‐linking reaction involving double bonds in isoeugenol‐based benzoxazine, at the same time, the integration of flexible long chains and rigid groups also endows the resins with shape memory property 165 . Combined with the Schiff base reaction between aldehyde group and polyether amine 166 or copolymerization with epoxidized vegetable oil, 167 vanillin‐based shape memory resins were developed as well.…”