Preparation And Antibacterial Activity Of Modified Shell Powder And Its Application In Polypropylene Composites

Focus on the discarded shells as the research object, this paper mainly solve the pollution of waste shells, as well as the reuse of the abandoned shell resources. Prepared the shell waste as a carrier material loaded with silver, and studied on the antibacterial properties of inorganic antibacterial material. What’s more, researched on the surface modification of the shell powder with the Furfural, and added thus modified powder into polypropylene to prepare the composite material. Researched on the mechanics performance, thermal performance and crystallization performance of the composite material, the main research contents and results are as follows:The inorganic antibacterial material was prepared using shell waste as a carrier material loaded with silver. It was characterized and analyzed by X-ray diffraction(XRD), scanning electron microscopy(SEM) equipped with an energy dispersive spectrometer (EDS), X-ray photoelectronic spectroscopy (XPS) and N2adsorption isotherms. The antibacterial activity was evaluated using Staphylococcus aureus and Escherichia coli as sensitive indicator strains. The antibacterial mechanism was probed and discussed as well. Silver carbonate was detected in the prepared material through XRD analysis. XPS measurement and EDS analysis also confirmed the loading of silver onto the carrier. The antibacterial test demonstrated that the prepared material had good antibacterial property, especially against E. coli. Based on the silver ion release and pH test, as well as comparatively analyzing the characteristics of carrier material and prepared material, we proposed that the antibacterial mechanism mainly involved the antibacterial activity of silver ion, slightly higher pH value and supplementary photocatalytic antibacterial activity of silver carbonate.The clam shell was modified by furfural and then introduced as a filler to reinforce polypropylene (PP). The mechanical and crystallization properties of PP composites were investigated as well. The results showed that the particle size of modified powder became smaller as compared with that of raw shell powder and it could significantly improve the interfacial compatibility between filler and PP matrix. With the filling contents increasing, the elongation at break of PP composites displayed an increasing trend. When the filling ratio was7%, the elongation at break reached a maximum of140%. Compared with unmodified shell powder, the crystallinity of PP/modified powder composites decreased slowly. Polarizing microscope observation showed that the typical cross pattern of light extinction for PP became more and more unobvious with the increasing of filling ratio, and the number of a-spherulites also decreased. Therefore, the modified powder could promote the heterogeneous nucleation of PP.