Том 49, № 2 (2017)

The mechanism for the formation of chemically-heterogeneous polyethylene terephthalate (PETP) under industrial manufacturing conditions from dimethyl terephthalate and ethylene glycol was discussed in light of the results of a study of this polymer and the derived polymer gel. The chemical heterogeneity of PETP is attributed to side-reactions leading to the formation of relatively small bent macromolecules with short side-chains branchings.

The rheological characteristics of dilute solutions of silk fibroin in 1-butyl-3-methylimidazolium acetate were studied. It was found that the characteristic viscosity depends on the conditions under which the solutions were prepared. Films of silk fibroin were obtained from the solutions. Their structural, mechanical, and thermal characteristics were determined.

Polymer composites based on polyester resin with nanodiamonds and with activated nanodiamonds were investigated in vacuo (10^–6 Pa) on an ES 2401 spectrometer using a magnesium anode and 0.1-eV resolution. The sample topography was studied by atomic-force microscopy on a Solver 47 PRO scanning probe microscope in contact mode using a CSG probe. The strength characteristics were measured as a function of nanodiamond concentration. It was shown that activated nanodiamonds could be used to increase the resin strength characteristics.

Optical glass fibres act as a light transmitting conduit, do not conduct electricity, and transmit data with a high speed and over long distances. During winding of special optical glass fibres on spools having flanges, because of generation of axial pressure that causes deformation of the flanges, the marginal coils may slip into the gaps between the winder and the spool flanges, which disrupts parallel arrangement of the fibres in the cut bundle and lengthens packing time. During unwinding of the fibres, because of decrease in axial pressure, the marginal coils may get pinched, leading to tearing of the fibres. In this work, we made an analysis of the axial pressure and flexures of the spool flanges and determined the effect of flange size, winding tension, and thickness of winding on the absence of fibre slipping.

The movement of condensate droplets in the channel of a drying drum is considered. The dependence of the critical droplet radius on steam velocity in the channel is calculated. Conclusions are drawn regarding the limits of the most appropriate steam flow velocity.

During polymeric yarn transport, it is very important to maintain a fixed tension, which prevents defects of end products. For this, it is essential to study the object control dynamics by experimental identification, the essential aspect of which lies in removal of transient characteristics and their subsequent approximation by transfer functions. The transient characteristics were removed on an operating equipment. The motor speed was taken as the input action and the tension readings from a TS44 tension sensor, as the output value. During the experiment, the required number of transient characteristics was removed and they were averaged to get the average transient characteristic.

With the expanding assortment of reinforcing fillers, including three-dimensional woven fabrics and woven preforms made of continuous fibers, the development of techniques for determining their physicomechanical characteristics, which is one of the key parameters in the incoming control of the reinforcing filler, is becoming highly topical. The article gives an overview of the current state of production of reinforcing carbon fillers, the main producers, types of reinforcing carbon fillers and methods for their production.

Sequential deposition on the surface of a silica fiber of oxide and polyaniline layers produced an organic—mineral coating that could catalyze redox destruction of organic dyes. The sensitizing effect of polyaniline allowed the catalysts to be used to purify wastewater from finishing works under natural lighting.

The surfaces of various organic fibers were studied by atomic-force microscopy. Parameters characterizing the roughness of individual filaments in special-purpose yarns were determined. The results allowed the yarn textile processing conditions to be predicted and the loom fittings and textile modifiers for treating the yarns to be rationally selected.

The problems of the reliability of the prediction of the relaxation and deformation properties of polymer materials in the region of action of nondestructive loads close to the conditions of their operation are considered on the basis of mathematical modeling of the relaxation and creep processes. For practical evaluation of the reliability of this prediction, integral criteria are obtained on the basis of the determining equations of deformation and relaxation processes of these materials.