| Polypropylene(PP),as a universal resin, is closely related with our daily lives. It is widely used in the automotive, consumer products and packing fields because of its low density, processed easily and high mechanical properties. But there is a weak point of the low impact strength especially at low temperatures. Therefore, reducing the low-temperature brittleness, improving their mechanical properties and the preparation of polypropylene plastic with a specific function is becoming a trend.Molecular Sieves, a class of crystalline silicate or aluminosilicate, are channel and cavity systems of molecular size, typically 0.3-2.0 nm, formed by silicate or aluminum tetrahedra through oxygen bridge bond, which have the characteristics of molecular screening. Its unique structure and properties are a long-range order of pore structure, narrow pore size distribution, high porosity, and large surface area, etc. Molecular Sieve, as an inorganic material, mainly used in catalyst carriers, adsorbents etc. However, the study of the Molecular Sieve encapsulating metal oxide as inorganic fillers of polymers is still few.Zinc oxide is an inorganic material with more extensive application prospect. Nano-Zinc oxide reveals a strong ability of absorbing UV and shielding effect of UVA (320nm-400nm) and UVB (280nm-320nm) especially. Nano-Zinc oxide also has some antibacterial and deodorizing effect, which can be in the products of deodorizing and antibacterial materials. In addition, nano-zinc oxide is a material of non-toxic, tasteless, good stability and colored easily according to the practical application. So it is mainly used in electronic and optical devices, gas meter, pressure-sensitive anti-aging resistance and antibacterial material, etc.In this paper, three different Molecular Sieves loading zinc oxide are prepared by different post-processing. The first one is the Molecular Sieves adsorpting zinc oxide only in the hole, the second is the Molecular Sieves adsorpting zinc oxide both inner surface and outer surface of the Molecular Sieves stably, and the last is the mix of the second and pure zinc oxide. Fluorescence spectroscopy and X-ray diffraction (XRD) are introduced to investigate the different Molecular Sieve samples. The composites of Molecular Sieves/PP with different Molecular Sieves content are prepared by melt mixing and made into films. The composites films are investigated by Fourier transform infrared spectroscopy (FTIR), DSC, Fluorescence Spectrum, XRD, polarizing microscopy (POM), and antibacterial experiments. The experimental results are as follows:1. The adsorption of zinc oxide has been successfully into the molecular sieve pore. The adsorption to zinc oxide of external surface will also happen. Therefore, different post-processing of Molecular Sieves after absorption is the key when the different samples are prepared.2. Molecular Sieves play a role of heterogeneous nucleation on the PP. the crystallization peak temperature of composite materials have increased with the increased content of Molecular Sieve. And the addition of Molecular Sieve can induce the formation ofβcrystalline. The highest contentβ-crystal can be obtained in 3wt% Molecular Sieves/PP.3. The composites of modified Molecular Sieves/PP show better anti--Staphylococcus aureus than Escherichia coli role to some extent. The ZnO-in powder sample works best to Staphylococcus aureus and Escherichia coli and T-ZnO worst among three samples. Among three films T-ZnO /PP has the best antibacterial effect and ZnO-in/PP worst.4. The addition of Molecular Sieves has an effect on UV and thermal aging. The samples S and ZnO-in can restrain the aging of PP caused by UV for short times, but it is invalid for long hours. However, B-ZnO and T-ZnO can play for a long time in terms of inhibiting UV aging of PP. For thermal aging of PP in process, S,ZnO-in and B-ZnO inhibit the occurrence of thermal degradation in process ,but T-ZnO do not work. |
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