We report a cost-efficient and easy to implement process for fabricating microfluidic reactors in thermoplastic materials. The method includes (i) the fabrication of an imprint template (master), which consists of a photoresist deposited on a metal plate; (ii) the thermoembossing of the reactor features into polymer sheets; (iii) the activation of the embossed and planar thermoplastic surfaces; and (iv) the low-temperature bonding of these surfaces. The generality of the method is established by fabricating microfluidic reactors with a complex geometry in a range of thermoplastic polymers, including cycloolefin, polycarbonate, and UV-transparent acrylic polymers and by the multiple, high-fidelity use of the master.

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667.64:678.026 V. A. Pakharenko, and V. V. EfanovaThe advantage of basalt fibres in comparison to glass fibres was demonstrated. The process parameters for production of basalt fibre are reported. The manufacturing processes in processing polypropylene composites with low combustibility and poly(ethylene terephthalate) composites filled with basalt fibres in lines based on a cascade screw-disk extruder are examined. Technology for obtaining polymer coatings using composites with basalt flakes and their properties are described.Glass and basalt fibres have become most common as mineral fibre fillers in production of polymer composite materials.The strength of basalt fibre is a function of its diameter. When the diameter increases from 7 to 13 μm, the strength of the fibre decreases from 2800 to 2000 MPa. Use of glass fibres of sodium-calcium-silicate composition is restricted to the temperature of 723-773 K, and alkali-free fibres are restricted to a temperature of 873-973 K. Basalt fibres are used at temperatures up to 1023-1073 K. At 973 K, the strength of basalt fibres only decreases by 50% with respect to the initial strength (glass fibres are destroyed at that temperature).Basalt fibres, like glass fibres, belong to the class of chemically stable fibres. At the same time, in contrast to glass fibres, higher resistance to aging and weatherproofing are characteristic of them. Basalt fibre withstands repeated treatment with live steam with no change in the properties.A 1-5% change in the humidity decreases the strength of glass fibres by 20-30% while the strength of basalt fibres is almost unchanged after 60 days in conditions of 100% relative humidity.If we compare glass fibre (GF), asbestos fibre (AF), and basalt fibre (BF), the advantage of BF can be noted: AF has limited application due to carcinogenicity, while GF changes the strength of fibreglass plastics during use and causes pulmonary silicosis.Basalt fibres are made from rocks. The approximate composition of BF is reported in Table 1. High thermal stability and chemical resistance, especially to bases, low water absorption, and good adhesion to polymers are characteristic of basalt fibres in comparison to glass fibres. The greatest advantage of basalt fibres is the high modulus of elasticity, equal to or greater than the modulus of elasticity of quartz and special high-modulus glass fibres. To create high-modulus glass fibres, special additives are incorporated in the glass melt; this changes the process conditions and significantly increases their cost, and basalt fibres have high elastic properties from the beginning.Basalt stock is melted at a temperature of 1450°C, the fibre is drawn through a platinum spinneret with pull rollers and it is then fed into a blowing chamber. The fibre is blown into a superfine fibre 3-7 μm in diameter and 50-70 cm long, and the density is 23-30 g/cm 3 . The temperature of use varies from -260 to +600°C and the moisture content does not exceed 2%. In order to not destroy the surface of BF and to increase adhesion betwe...

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