The nature of bonding matters: Benzoxazine based shape memory polymers

A novel shape memory polymer is presented based on polybenzoxazine and poly(ε-caprolactone) (PCL). Polybenzoxazines with unbound and covalently incorporated PCL were prepared applying hydroxyl and tosyl terminated PCLs, respectively. Thermo-responsive and shape memory behavior with high shape fixity and recovery were demonstrated for samples containing a high ratio of covalently bonded PCL in a crosslinked benzoxazine structure. Samples with exclusively non-bonded PCL chains proved to be brittle, possessing a heterogeneous morphology and lacking shape memory properties. The type of bonding into benzoxazines network – covalent versus non-covalent bonding of PCL – strongly affects materials structure property relationship. [Display omitted] •A shape memory polymer based on benzoxazine and polycaprolactone was synthesized.•Tosyl end groups enable partial crosslinking of PCL into benzoxazine network.•PCL/polybenzoxazine samples showed different phase morphologies.•Partial crosslinking is essential for molding and fixing processes.