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A challenge in the design of shape‐memory polymers (SMPs) is to achieve high deformability with a simultaneous high shape recovery ratio. Here we explored, whether SMPs featuring large deformation capability and high shape recovery ratios can be created as polymer networks providing two kinds of netpoints based on covalent bonds and physical interactions. As a model system, we selected poly(carbonate‐urea‐urethane)s (PCUUs) synthesized by a precursor route, based on oligo(alkylene carbonate) diols, isophorone diisocyanate (IPDI), and water vapor. The PCUU networks exhibited a one‐way shape‐memory effect (1W‐SME) with programmed strains up to εprog = 1000% whereby they provided excellent shape fixity (92–97%) and shape recovery (≥99%) ratios. The switching temperatures (Tsw) varied between 36 and 65 °C and increased with the increasing molecular weight of the oligo(alkylene carbonate) diol and length of the hydrocarbon chain between the carbonate linkages. Tsw was also influenced by the strain applied during programming (εprog). Poly(carbonate‐urethane)s have been reported to have good biocompatibility and biostability, which in the combination of high‐strain capacity and high Young's modulus makes the obtained PCUUs interesting candidate materials suitable for medical devices such as medical sutures or vascular stents. Copyright © 2016 John Wiley & Sons, Ltd.

The presented research focuses on the synthesis and structure–properties relationship of poly(carbonate-urea-urethane) (PCUU) systems including investigations on shape memory effect capability. Furthermore, we approached the topic from a broader perspective by conducting extensive analysis of the relationship between the synthesized compounds and the results of computer simulations by means of the Monte Carlo method. For the first time, by using a unique simulation tool, the dynamic lattice liquid model (DLL), all steps of multi-step synthesis of these materials were covered by the simulations. Furthermore, broad thermal, mechanical, and thermomechanical characterization of synthesized PCUUs was performed, as well as determining the shape memory properties. PCUUs exhibited good mechanical properties with a tensile strength above 20 MPa, elongation at break around 800%, and an exhibited shape memory effect with shape fixity and shape recovery ratios above 94% and 99%, respectively. The dynamic lattice liquid model was employed to show the products and their molar mass distribution, as well as monomer conversion or the dispersity index for individual reaction steps. The results obtained in the following manuscript allow the planning of syntheses for the PCUUs of various structures, including crosslinked and soluble systems, which can provide a broad variety of applications of these materials, as well as a better understanding of the composition–properties relationship.