Shape memory polymers (SMP) are prepared, via dual thiol‐epoxy/thiol‐ene reactions, from diglycidyl ether of bisphenol A (DGEBA), a trithiol (TMP), a tetraallyl amine (TAA), and small amounts (0.1–0.5 wt.%) of graphene oxide either pristine (GO) or functionalized with methacrylate groups (GOM). The incorporation of GOM to the epoxy resin network permits a good load transfer, which is reflected in improved properties such as Young modulus (from 220 to 519 MPa), tensile strength (from 46.3 to 69.2 MPa), Izod impact strength (from 0.051 to 0.42 J/mm), torque (from 0.008 to 0.031 Nm), and glass transition temperature (from 75 to 105°C). Such improvement in properties is attributed to the incorporation of GOM via covalent linking, which is a good strategy for improving polymer‐particle interaction and particle dispersion. The epoxy‐based SMP also show high storage modulus (up to 2.36 GPa) and high deformation capacity, which are reflected in good shape fixity (between 97% and 100%) and thermo‐induced shape recovery (between 97% to 99.7%) behaviors in flexion mode tests.

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In this work, the microwave synthesis of Nylon-6 hybrid polymeric nanocomposite (HPNC) was studied by the polymerization of ε-caprolactam, 6-aminocaproic acid, and 2% wt of silver nanoparticles (Ag-NPs). It was determined that the dielectric heating (DH) of the Ag-NPs controls the thermal behavior of the HPNCs synthesis and triggers the chemical reaction between Ag-NPs and the Nylon-6 molecules. Such reaction promotes their coating with the polymer and their precipitation, which affects the agitation of the reaction mixture, and results in broader molecular weight distribution and three HPNC populations. Usually, the power output effect in these processes is thermal as it accelerates their heating rate. Still, for HPNCs, higher output reduces the agglomerate size of the Ag-NPs and accelerates their precipitation. At power up to 600 W, the DH of the Ag-NPs causes the explosion of the reaction vials.The antimicrobial activity of the HPNCs against P. aeruginosa is almost 100% effective at 180 min of exposure; therefore, this microwave synthesis process is suitable for producing antimicrobial HPNCs.

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