Vitrimers are fascinating thermoset polymers to the industry since they can be recycled and reprocessed without compromising their mechanical strength and solvent resistance. Particularly, transesterification reaction in the epoxy resin (ER) vitrimers usually requires the incorporation of a catalyst, whereas most reports only focused on investigating the catalytic effect of small molecules, such as zinc acetate (Zn­(OAc)2) and triazabicyclodecene (TBD). In this work, a polymer catalyst, poly­(acrylonitrile-co-zinc methacrylate) (Zn-PAM), was synthesized by the random copolymerization of zinc methacrylate and acrylonitrile, where the transesterification catalysis efficiency of Zn-PAM was systematically investigated and compared to that of Zn­(OAc)2 and TBD by temperature-dependent stress relaxation experiments. It was revealed that Zn-PAM has a higher catalysis efficiency than Zn­(OAc)2 and TBD under the same loading between Zn2+ and TBD. Besides, only a tiny amount of polymer catalyst is needed to efficiently catalyze the transesterification reaction while in the meantime enhance the mechanical properties of ER.

As an emerging class of dynamic cross‐linked network, vitrimers have attracted much attention due to the combination of mechanical advantages of thermosets and recyclability of thermoplastics at an elevated temperature. In particular, most vitrimers with multi‐shape memory properties usually involve more than one thermal transition or molecular switch, which might pose a challenge for facile sample fabrication and potentially limits their applications. In pursuit of a more universal and simple route, utilizing commercially available and inexpensive reagents to prepare shape‐memory vitrimers with dual cross‐linked network from vinyl monomer‐derived prepolymers is reported here. Copolymerization of desired vinyl monomers gives prepolymers containing carboxyl and zinc carboxylate groups, which are later converted into vitrimers in a single step by post‐curing with diglycidylether of bisphenol A. The Zn2+ ions can not only act as physical crosslinking points through ionic coordination interactions, thus providing the triple‐shape‐memory properties, but also play the role of catalyst to activate transesterification in the dynamic covalent network. This new self‐catalyzed vitrimer has excellent transesterification efficiency, triple‐shape‐memory properties, and can be sufficiently healed and reprocessed at an elevated temperature. The proposed molecular design of self‐catalyzed materials opens a new avenue toward commercially relevant fabrication of high‐performance vitrimers with multiple shape‐memory properties.

Photoluminescence from blue fluorescence to green, yellow, and orange phosphorescence can be switched via multiple stimuli on an asterisk-shaped compound.

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