In this work, a great synergistic effect of 2D clay platelets and 1D carbon nanotubes (CNTs) on reinforcing chitosan matrix has been observed for the first time. With incorporation of 3 wt % clay and 0.4 wt % CNTs, the tensile strength and Young's modulus of the nanocomposites are significantly improved by about 171 and 124%, respectively, compared with neat chitosan. This could be understood as due to the formation of much jammed fillers network with 1D CNTs and 2D clay platelets combined together, as indicated by rheological measurement. Our work demonstrates a good example for the preparation of high performance polymer nanocomposites by using nanofillers of different dimension together.

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Polyvinyl alcohol (PVA)/gelatin composite fibers containing carbon nanotubes (CNTs) had been prepared by wet-spinning method. A remarkable increase of tensile strength of the PVA/gelatin fibers was achieved by adding small amount of CNT. The mechanism of reinforcement has been studied using a combination of differential scanning calorimetry (DSC), 2D wide-angle X-ray diffraction (2D-WAXD) and scanning electron microscopy (SEM). SEM showed a decreased gelatin domain size by adding CNTs, suggesting a possible compatibilization effect between PVA and gelatin. On the other hand, an increased crystallinity and degree of orientation of PVA/gelatin fibers has been observed by adding CNTs. Thus, the increased compatibilization, crystallinity and degree of orientation in PVA/gelatin/CNTs composite fibers should be the reasons for the observed increase of mechanical properties.

A novel change of phase behavior and properties of polyvinyl alcohol (PVA)/gelatin blends as a function of pH was reported. The PVA/gelatin blends were found to be completely miscible in acidic condition (pH < 4), partially miscible in basic condition (pH > 8), and immiscible in neutral condition (pH was ca. 6). As a result, the membranes cast from acidic condition showed the highest tensile strength and the lowest alcohol vapor permeation (AVP) rate; those obtained from neutral condition showed the lowest tensile strength and highest AVP rate; the properties of membranes cast from basic condition lay in between. The interaction between PVA and gelatin was investigated via Fourier transform infrared spectrum (FTIR), differential scanning calorimetry (DSC), and Zetasizer measurement. The novel pH‐dependence of the blends was ascribed to the protonation of amino groups of gelatin in acidic condition, which resulted in a strong electrostatic attraction between NH of gelatin and OH of PVA. The partial miscibility in basic condition was due to the ionization of carboxyl groups of gelatin, which caused a stretching of gelatin via electrostatic repulsive force and a breakage of the H‐bonding among the molecular chains, leading to a limited interaction between PVA and gelatin and forming a partially miscible blend. In neutral conditions, there were almost no charges (very limited protonation and ionization) at the weak polyampholyte gelatin, and the strong H‐bonding among gelatin molecules themselves or PVA molecules themselves caused the phase separation between gelatin and PVA. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 239–247, 2009

Carbon based dots nanoclusters (CDCs) are reported for the first time. The morphologies of the obtained CDCs are characterized by transmission electron microscopy and atomic force microscopy. It is found...

Graphene/carbon-based dot nanohybrids were prepared by the ultrasonic exfoliation of natural graphite in the presence of single-layer carbon based dots, and used for the electrochemical production of hydrogen peroxide.

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