In this paper, metallocene polypropylene (mPP) composites filled with carbon nanotubes (CNTs) were prepared using twin-screw extruder. The crystallization behavior, mechanical properties and rheological behavior were characterized by a differential scanning calorimetry (DSC), universal material testing machine and rotational rheometer. The results of DSC indicated that the effect of CNTs on heterogeneous nucleation of mPP was very obvious and the crystallizability of the resin matrix was improved after adding CNTs, especially the initial crystallization temperature (T0), crystallization temperature (Tc) increased by 9.63 °C and 8.28 °C when the CNTs content was 1.25 wt%. The yield stress and elastic modulus increased to 33.98 MPa and 1605.6 MPa as the CNTs concentration increased to 1.0 wt.% in contrast to that of the neat mPP. The results of SEM images showed that the better dispersion and adhesion of CNTs into polymer matrix. The results of rotational rheometer proved that interactions increased between CNTs and mPP as the content of CNTs increasing.

In this work, a high fluidity polypropylene prepared with the metallocene catalyst (mPP) was used as matrix, carbon nanotube (CNT) and continuous carbon fiber (CCF) were added to prepare composites, and their mechanical properties, melting and crystallization behavior were investigated. In the mechanical properties, the effects of tension force in the preparation process and compatibilizer maleic anhydride grafted polypropylene (MAPP) on the tensile strength of the composites were researched. The results show that the tensile strength of the composites increases first and then decreases with the increase of tractive force. In addition, the melting and crystallization behaviors and dynamic mechanical behaviors of mPP, CNT/mPP and CNT/CCF/mPP composites were characterized and studied by a differential scanning calorimetry (DSC) and dynamic mechanical analyzer (DMA). The results show that the melting point (Tm ), crystallization temperature (Tc ) and storage modulus (E') of CNT/mPP are all increased by adding 1wt% CNT, especially the Tc is increased by 8.8 ºC. It shows that after CNT was added to mPP as inorganic carbon material, it plays a prominent role in heterogeneous nucleation. After CCF was composited with CNT/mPP, the composites with CCF content of 30 and 42wt% were prepared, and their Tm , Tc , crystallinity (Xc ) and E' were all improved, especially E' was greatly improved, such as the initial E' was increased by 5.64 and 11.74 times. Even at the end of the curve, the E' of the composites with CF is still significantly higher than that of mPP and CNT/mPP. It indicates that adding CCF will greatly improved the deformation resistance and load deformation temperature of mPP.

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Controlling the optical properties of light-responsive organic molecules is essential for their application in photonics. We demonstrate how light-responsive organic polaritons formed inside an optical cavity can be used to...