Canadian scientists have developed an approach to treatment of tissues with mixture of polydimethylsiloxane to impart oleophobic properties and tested it on a metal mesh and nylon jacket. Water and oil droplets formed with a treated nylon cloth edge angles greater than 90 degrees. A substance with a value of surface tension less than 24 millinewtons on the meter also formed a nonzero contact angle with a treated cloth. The results of a study published in the journal Nature Sustainability.
Non-wetting water and oil fabric are used as in the textile industry and in other industries. Clothing made of such material stays clean longer and keeps its original appearance. Usually oil repellent fabrics are treated with perfluorinated organic substances with low surface energy (about 10-20 millinewton per meter) that allows you to repel both aqueous and oil droplets. However, these compounds have a negative impact on the environment and human health. Materials in which no perfluorinated substances commonly have a surface tension higher than 24 millinewton per meter that is not oil repellent. According to the theory of wetting, such material might still exist, if you choose the right surface structure of tissue and its chemical composition.
Chabanian Sadaf (Sadaf Shabanian) with colleagues from the University of British Columbia developed an approach to creating mixes for finishing of textiles without the use of perfluorinated substances, which after processing, tissues were repelled by oil. Finishing the mixture of polydimethylsiloxane applied to the fabric performed the role of nanoscale secondary structure, conducive maslotorgovli properties. The authors theoretically calculated geometrical parameters of the obtained fabric, which, in particular, according to presented in a mathematical formula, dependent on whether the fabric is to possess oleophobic properties. The theoretical assumptions researchers tested in the experiments with machined metal mesh and nylon fabric, placing them on drops of oil and water, and recording the contact angle.