Abstract：A solution method for modifying thermoplastic polyurethane (TPU) by the introduction of 3D functionalized nanohybrids composed of two-dimensional GONRs and one-dimensional CNTs was applied. FTIR, XRD, XPS and TEM were employed to characterize the structure and properties of GONRs-CNTs hybrids before and after modification. The functionalized GONRs-CNTs (pGONRs-CNTs)/TPU composite films were subsequently prepared by solution coating method on a coating machine. Furthermore, by means of oxygen transmission rate test, tensile test and the observation of surface morphology, the synergetic effect between GONRs and CNTs and the effect of different pGONRs-CNTs content on the barrier and tensile properties of TPU composite films were also studied. The results show that a unique three-dimensional (3D) crosslinked nanostructure is successfully obtained, in which GONRs are bridged by CNTs. We also find that the as-prepared pGONRs-CNTs with neat shape and low defect are evenly dispersed in TPU matrix and form strong interfacial adhesion with the matrix, while the existing of CNTs play the role of supporting frame to prevent GONRs from sliding and aggregation; modified by phenyl isocyanate, the lipophilicity of pGONRs-CNTs composite is obviously improved, while, by the introduction of huge isocyanate, the interlayer spacing is further improved, which is good for uniform dispersion in the polymer matrix. As a result, when the mass fraction of pGONRs-CNTs is 0.5%, the barrier and tensile properties of pGONRs-CNTs/TPU composite films reach to the optimal values:the oxygen transmission rate decreases by 63.08% and the tensile strength increases by 46.55%, compared with those of the neat TPU, which will lead to great benefit for the barrier and mechanical properties of TPU films.
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