Antibacterial polypropylene/Ag-kaolinite, preparation and characterization

Two types of kaolinites modified by formamide, ammonium bromide, vinylacetate (followed by polymerization insitu) and then treated with silver nitrate solution. Mixtures of polypropylene with silver/kaolinite (AgK) nanofillers, prepared by melt compounding technique and pressed into thin plates. Structure properties of prepared powder AgK materials and PP/AgK composites were studied using X-ray diffraction methods, scanning electron microscopy and the specific surface area measurement. Antibacterial properties of PP/AgK composites were tested on two different bacterial strains: Gram-positive, Enterococcus faecalis and Gram-negative, Pseudomonas aeruginosa. Surfaces of PP/AgK composites showed good antibacterial effect against both tested bacteria. The results showed improving effect to inhibit the bacterial growth with increasing content of AgK nanofillers in PP. © 2016 American Scientific Publishers All rights reserved

Organovermiculite nanofillers in polypropylene

Vermiculite (VER) was exfoliated to be used as organovermiculite nanofiller(ODA/VER) for polypropylene (PP)/VER nanocomposites. We used three procedures. PI: low-temperature intercalation of melted octadecylamine (ODA) led to the regular bilayer arrangement of organic molecules in the interlayer space. P2: mechanical exfoliation of ODA/VER by jet milling decreased the crystallite size. P3: chemical exfoliation using an oxidizing agent potassium persulfate and subsequent intercalation with ODA created a mixture of monolayer and bilayer arrangements of organic cations in the interlayer. The thermal compounding of the organovermiculites (4 wt.%) with maleated PP at 30 and 50 rpm caused the partial deintercalation of the organovermiculite and organovermiculite pretreated with the oxidizing agent. The jet milled ODA/VER was very well dispersed within PP matrix. Thermal stability of PP and PP/VER nanocomposites with differently exfoliated ODA/VER nanofillers was evaluated by thermogravimetric analysis. (C) 2008 Elsevier B.V. All rights reserved