Dispersed copper (I) oxide particles encapsulated by polylactide

Abstract

One of the approaches for the production of polymer composite materials with a biocidal effect is based on the use of dispersed particles of some metal oxides as a filler (for example, copper oxide or zinc oxide). Such an approach allows not only providing a biocidal effect, but also increasing such mechanical characteristics as the modulus of elasticity, hardness, and abrasion resistance. The mechanical characteristics of such polymer composite materials can be controlled by formation of a sheath (for example, from polylactide) of a given thickness on the surfaces of dispersed particles. Polylactide is a biodegradable polymer, widely used as coating material for particles with biocidal properties. The parameters of the methods for forming a polylactide sheath are determined by the sheath’s thickness and the sheath’s adhesion to the particle surface. The purpose of the study was to determine the parameters of the polymer sheath’s formation on the surfaces of dispersed submicron copper oxide (I) particles during coacervation of polylactide from the solution. The encapsulation of copper (I) oxide particles was carried out by the coacervation process in a solution. Polylactide was displaced from the solution in benzene by hexane in the presence of copper (I) oxide particles. It was shown that a sheath thickness of about 250 nm can be obtained by using the polylactide sheath formation method. The recommended parameters of the polylactide sheath formation method were determined: solution temperature of 35÷38 °C, hexane volume not more than 30±2 ml. The sheath had weak adhesion to particle surfaces: adhesion was determined by the roughness of the particle surface. The mechanical characteristics of the epoxy resin ED-20 polymer composition filled with the encapsulated particles were considered in the study. The increase in the mechanical properties of the polymer composition with encapsulated particles in comparison with the samples of polymer composition with non-encapsulated particles was revealed. That can indicate the increased adhesion of encapsulated particles to such polymer matrix.

Keywords

• encapsulation
• dispersed particles of copper (i) oxide
• polylactide