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Thermoplastic polyurethane (TPU) nanocomposites incorporated with polydopamine functionalized graphene nanoplatelet (PDA-GNP) were prepared by in situ polymerization. Fourier transform infrared spectroscopy results indicated that the addition of PDA-GNP could promote the formation of hydrogen bonding and microphase separation. The microstructure obtained from small-angle neutron scattering indicated that the addition of PDA-GNP increased the number while significantly it decreased the size of hard microdomains. Scanning electron microscopy demonstrated that PDA-GNP exhibited strong interfacial interactions with TPU matrix. In particular, the tensile strength, strain at break, and toughness of TPU/PDA-GNP with as low as 0.5 wt % PDA-GNP increased by 313, 16, and 279%, respectively. This individualized phenomenon was attributed to the abundant covalent bonding between PDA-GNP and TPU resulting in strong interfacial interactions and good compatibility specifically associated with the changes of TPU microstructure.

Multiwalled carbon nanotubes functionalized with an imidazolium-type ionic liquid polymer, PIL(BF 4 )-MWCNTs, have been successfully prepared via in situ free radical polymerization of 1-vinyl-3methylimidazolium iodide ([VMIm][I]) and then blended with poly(2,6-dimethyl-1,4-phenylene oxide) containing imidazolium groups (PPO-MIm) in solution to fabricate composite membranes. The composite membranes were characterized by scanning electron microscopy (SEM) and the SEM images of the membranes show that the PIL(BF 4 )-MWCNTs can be homogeneously dispersed in the PPO-MIm matrix.The conductivity and mechanical properties of the composite membranes were examined. It was demonstrated that the incorporation of the PIL(BF 4 )-MWCNTs into the membranes of PPO-MIm can increase both conductivity and mechanical properties. The composite membrane containing 0.3 wt% of PIL(BF 4 )-MWCNTs (P(0.3)) exhibits a dramatic enhancement in ionic conductivity (95.3%) and tensile strength (82.9%) in comparison with the membrane without PIL(BF 4 )-MWCNTs. Therefore, this research demonstrates that the incorporation of functionalized carbon nanotubes is a facile and useful strategy for improving both ionic conductivity and mechanical properties of alkaline polymer electrolyte membranes.

Thermoregulated rigid polyurethane foams containing silica shelled nanoencapsulated phase change materials (NanoPCMs) were fabricated. Chemical composition and morphology of the composite foams were characterized by Fourier transform infrared (FT-IR) spectroscopy and scanning electron microscopy (SEM), respectively. Thermal properties of the composite foams were evaluated by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and dynamic mechanical thermal analysis (DMTA) methods. The NanoPCMs are homogeneously dispersed in a polyurethane matrix. Higher NanoPCMs contents in the composite foams lead to slightly increased cell size, minor decrease of glass transition temperature (T g ), and higher phase change enthalpies. The composite foams exhibit good thermal reliability, reasonable thermoregulation property, and fairly high compressive properties. In addition, the compressive property-density relationship for the composite foams agrees well with the Gibson− Ashby's power law.