To find out whether Al2O3 nanofiller is effective in improving the characteristics of polymer composites, composite polymer films based on biodegradable polylactide and epoxidized aluminum oxide nanofibers were obtained by solution casting. Surface morphology, mechanical and thermal properties of composites were studied by SEM, IR-Fourier spectroscopy, DSC and DMA. It was shown that, below and above the percolation threshold, the properties of the films differ significantly. The inclusion of alumina nanoparticles up to 0.2% leads to a plasticizing effect, a decrease in the crystallization temperature and the melting enthalpy and an increase in the tensile stress. An increase in the content of alumina nanoparticles in films above the percolation threshold (0.5%) leads to a decrease in the crystallinity of the films, an increase in stiffness and a drop in elasticity. Finding the percolation threshold of alumina nanoparticles in PLA films makes it possible to control their properties and create materials for various applications. The results of this study may have major significance for the commercial use of aluminum oxide nanofibers and can broaden the research field of composites.

Potato cyst nematodes (PCNs) pose a great challenge for potato cultivation throughout the world. Being a rather difficult parasite due to a number of its physiological features, specifically a long-term viability of the eggs, PCNs cause drastic damage to worldwide agriculture. There are several approaches to prevent the spread of these pests, primarily using synthetic nematicides as well as biological products on a bacterial and fungal basis and application of agrophytocenotic methods. However, each of these conventional approaches has its considerable disadvantages. As a result, given the high yield losses caused by PCNs and the limited efficacy of conventional approaches to deal with this problem, a new means of pest control needs to be sought and researched. Development of long-acting preparations deposited with nematicidal ingredients could be a novel prospective approach for PCNs management.

The degradation pattern of bacterial poly-3-hydroxybutyrate (PHB) in dimethylformamide (DMF) and dioxane solutions at 100 °C assisted by ethylenediamine, 1,4-diaminobutane and monoaminoethanol was studied. When diamines were introduced into the PHB solution in DMF in the amount of 1 mol of the reagent to 5 or 10 mol of PHB monomers, a rapid decrease in the molecular weight of the polymer was observed. The initial value of the weight average molecular weight (Mw) 840 kDa had decreased by 20–30 times within the first 10–20 min of the experiment, followed by its gradual decrease to several thousand Da. When a similar molar quantity of aminoethanol was added, the molecular weight decreased slower. PHB had been degrading much slower in the dioxane solution than in DMF. By varying the number of reagents, it was possible to reach stabilization of the Mw at 1000–3000 Da when using diamines and 8000–20,000 Da using aminoethanol. 1H NMR analysis of the oligomers revealed of amino and amido groups forming in their structure. From the opposite end of the polymer chain, residues of 3-hydroxybutyric, crotonic and isocrotonic acids were formed during degradation. Differential scanning calorimetry indicated that after oligomerization there was a decrease in the melting point from 178 °C to 140–170 °C depending on the decrease in the molecular weight. The method proposed can be used for obtaining aminated PHB oligomers.

The need for a long-term sustaining of optimal concentrations of applied pesticides in the soil in agriculture resulted in the development of systems for controlled release of active substances. Such systems are based on the use of eco-friendly carrier materials that are harmless to plants, humans and environment. Inorganic substances (e.g., clays or alike substances), biodegradable polymers of natural or synthetic origin, blends of such polymers and their composites with inorganic fillers can be used as carriers. The deposited pesticides are released by diffusion or, in the case of systems based on biodegradable polymers, by degradation of the carrier. Inorganic carriers are usually impregnated with a pesticide. As for polymers, there is a wide range of methods for obtaining forms. Namely, these are the microsphere and nanoparticle formation, film casting, tablet pressing, form gelatinizing, and coprecipitation of a pesticide and a polymer from a solution. Co-extrusion of pesticides with polymers or their composites at temperatures below the degradation temperature of the components is another promising method for obtaining pesticide carriers.

The paper presents the results of a study of the effects of the"Monament-101" filler and the method of obtaining on the properties ofcomposite granules based on polycaprolactone (PCL). DSC and X-raydiffraction analysis showed an increase in the degree of crystallinity from52 to 67% and a slight decrease in the melting point (by 2oC) asthe clay was introduced into the polymer. Keywords: polycaprolactone, montmorillonite, composites, crystallinity, melting point. \