Emerging formulation technologies aimed to produce nanoemulsions with improved characteristics, such as stability are attractive endeavors; however, comparisons between competing technologies are lacking. In this study, two formulation techniques that employed ultrasound and microfluidic approaches, respectively, were examined for relative capacity to produce serviceable oil in water nanoemulsions, based on hempseed oil (HSO). The ultrasound method reached > 99.5% entrapment efficiency with nanoemulsions that had an average droplet size (Z-Ave) < 180 nm and polydispersity index (PDI) of 0.15 ± 0.04. Surfactant concentration (% w/v) was found to be a significant factor (p < 0.05) controlling the Z-Ave, PDI and zeta potential of these nanoparticles. On the other hand, the microfluidic approach produced smaller particles compared to ultrasonication, with good stability observed during storage at room temperature. The Z-Ave of < 62.0 nm was achieved for microfluidic nanoemulsions by adjusting the aqueous : organic flow rate ratio and total flow rate at 4:1 and 12 mL/min, respectively. Further analyses including a morphology examination, a simulated gastrointestinal release behavior study, transepithelial transport evaluations and a toxicity test, using a Caco2-cell model, were performed to assess the functionality of the prepared formulations. The results of this study conclude that both approaches of ultrasound and microfluidics have the capability to prepare an HSO-nanoemulsion formulation, with acceptable characteristics and stability for oral delivery applications.

An efficient sorbent for magnetic solid-phase extraction was developed from Fe 3 O 4 nanoparticles covered with aminated hypercrosslinked polystyrene. The sorbent has a saturation magnetization of 47 emu/g and a surface area of 509 mg/g and was tested for the extraction of 11 phenols from aqueous media. The optimum conditions were as follows: pH 3; adsorbent mass, 20.0 mg; adsorption time, 30 min; eluent (acetone) volume, 0.5 mL; and desorption time, 5 min. The enrichment factor after desorption reached 1595-1716 and the maximum adsorption capacity was 501-909 mg/g. Capillary electrophoresis was applied successively to separate 11 phenols after solid-phase extraction. The best separation was achieved using a fused silica capillary and borate buffer (pH 10.7) as a supporting electrolyte. After optimization, the linearity range was from 0.2 to 950 μg/L, and the limits of detection were 0.05-0.2 μg/L. The relative standard deviation varied from 6.1 to 8.7% (C = 1 μg/L) and from 2.9 to 3.5% (C = 500 μg/L). The determination of phenols is complicated in eutrophic water and spring water with a high content of humic and fulvic acids.

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Synthetic rubbers are the most common polymers. They are widely used in the production of a wide variety of products. The requirements for the quality of the obtained polymers constantly are increasing with a corresponding reduction in the cost and environmental tension of these industries. One of the effective areas that allow the production of synthetic rubbers to meet the requirements is the search and application of new technologies for the manufacture of emulsion rubbers. One of the problematic stages in the production of emulsion rubbers is their isolation from latex. Agents that reduce the stability of latex dispersions have low resistance to biological oxidation and are capable of chemically binding the components of the emulsion system, as well as being almost completely removed from wastewater discharged to treatment plants, used to solve this problem. The work presents the results of the use of fertile, a by-product of the production of pressed baker’s yeast, in the technology of styrene-butadiene rubbers production. Its effect on the process of isolation of rubber SKS-30 ARC from latex has been studied. The costs of acidifying and coagulating agents have been determined. The effect of pH medium on the process of rubber isolation from latex at various dosages of fertile has been studied. Rubber compounds based on rubber SKS-30 ARC have been prepared using standard components and they have been vulcanized. The resulting vulcanizates in terms of performance have met all the requirements.

Natural wood is the most common natural polymer material that is affordable, non-toxic and widely used in various fields of industry and construction. However, wood also has disadvantages, to eliminate which it is modified with the use of organic and inorganic agents, oligomers and polymers that can protect it from external factors. The paper studies the possibility of using such a vinylaromatic monomer as α-vinylnaphthalene for modification and protective treatment of natural birch wood. It is shown that during processing in the conductive elements of birch wood under the influence of elevated temperatures, the polymerization of α-vinyl naphthalene proceeds by a radical mechanism. However, 100 % conversion of α-vinylnaphthalene and polyvinylnaphthalene cannot be achieved. Thus, the conductive elements of natural wood contain a composite consisting of α-vinyl naphthalene and polyvinyl naphthalene. It is shown that with an increase in the content of the proposed modifier in birch wood, water absorption and swelling of wood-polymer-monomer composite samples significantly decreases. This will increase the service life of products based on modified wood. The introduction of the proposed technology for modifying low-value wood species will contribute to the conservation of forest resources and their rational use