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EN
The work proposes a new method of hydrophobization of limestone powder from stearic acid vapour or stearic acid ether solution. The obtained product is characterised by all properties typical of water-resistant materials. The evaluation of these properties has been carried out according to Polish Standard PN-G-11020 and analysed with research methods originally used for powder technique.
EN
Nature inspires the design of synthetic materials with superhydrophobic properties, which can be used for applications ranging from self-cleaning surfaces to microfluidic devices. Their water repellent properties are due to hierarchical (micrometer- and nanometre-scale) surface morphological structures, either made of hydrophobic substances or hydrophobized by appropriate surface treatment. In this work, the efficiency of two surface treatment procedures, with a hydrophobic fluoropolymer, synthesized and deposited from 1H,1H,2H,2H-perfluorooctyltrichlorosilane (PFOTS) is investigated. The procedures involved reactions from the gas and liquid phases of the PFOTS/hexane solutions. The hierarchical structure is created in an epoxy nanocomposite surface, by filling the resin with alumina nanoparticles and micron-sized glass beads and subsequent sandblasting with corundum microparticles. The chemical structure of the deposited fluoropolymer was examined using XPS spectroscopy. The topography of the modified surfaces was characterized using scanning electron microscopy (SEM), and atomic force microscopy (AFM). The hydrophobic properties of the modified surfaces were investigated by water contact and sliding angles measurements. The surfaces exhibited water contact angles of above 150° for both modification procedures, however only the gas phase modification provided the non-sticking behaviour of water droplets (sliding angle of 3°). The discrepancy is attributed to extra surface roughness provided by the latter procedure.
EN
The paper deals with fabrication of carbonized and hydrophobized clinoptilolite-rich tuff using organic carbon rich substances, here particularly starch and waste vegetable residues, which were pyrolytically combusted and covered the external zeolite surface. Hydrophobization of the zeolite external surface was accomplished by octadecylammonium surfactant. Both surface modified clinoptilolite-rich tuffs were tested and compared with each other with regard to removal of organic (phenol) and inorganic (chromate, arsenate) pollutants from aqueous solutions. These elaborated composites with surface adsorbed pollutant species were analysed by X-ray photoelectron spectroscopy (XPS).
EN
The article presents information about moisture protection of building materials. The discussed parameters determining the efficiency of the water protection are material porosity, water absorptivity and surface condition of building materials. Moreover the ecological aspect of hydrophobic VOC-free preparations available on the market has been underlined. The first part of the article is a description of moisture problem in the building envelopes and the possibilities of its prevention. The special attention is put on the electric methods of moisture estimation with a special emphasis on the Time Domain Reflectometry (TDR) method. The second part of the article is devoted an experiment of model red-brick walls exhibited on capillary uptake process. For the experiment three model red-brick walls were built and prepared for water uptake process. The experiment was monitored by the capacitive and surface TDR probes thanks to which the necessity of sampling and material destruction could be avoided. Conducted experiments show the progress of water uptake phenomenon in the model walls which differ in type of protection against moisture and prove the potential of the non-invasive measurements using the surface TDR probes. Basic physical parameters of the applied bricks were determined together with the reflectometric measurements. Furthermore, Scanning Electron Microscopy (SEM) was used to analyze the hydrophobic layer continuity.
PL
W artykule przedstawiono parametry materiałów budowlanych, które wpływają na skuteczność stosowania preparatów hydrofobowych. Należą do nich porowatość, nasiąkliwość i stan powierzchni. Podkreślono również ekologiczne aspekty stosowania dostępnych na rynku budowlanym hydrofobowych preparatów wolnych od lotnych związków organicznych. Pierwsza część pracy jest omówieniem problemów wilgotnościowych w przegrodach budowlanych. Duży nacisk położono na elektryczne techniki detekcji wilgoci ze szczególnym uwzględnieniem metody TDR. Druga część ma charakter eksperymentalny. W celu zbadania zjawiska podciągania kapilarnego przygotowano trzy modelowe ścianki z cegły ceramicznej pełnej. Omawiany proces był monitorowany za pomocą czujników pojemnościowych oraz powierzchniowych sond TDR. Uzyskane wyniki pozwalają na śledzenie procesu podciągania kapilarnego w modelowych ściankach z cegły ceramicznej różniących się od siebie rodzajem zastosowanego preparatu hydrofobowego i potwierdzają możliwości sondy powierzchniowej TDR w pomiarach wilgotnościowych murów. Równolegle do badań za pomocą technik elektrycznych wyznaczono podstawowe parametry fizyczne cegły wykorzystanej do wymurowania ścianek, wykonano również zdjęcia za pomocą skaningowego mikroskopu elektronowego (SEM) w celu przeanalizowania ciągłości warstwy hydrofobowej.
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