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A literature review on the production of thermoplastic starch (TPS) with various plasticizing additives as a component of biodegradable polymer compositions was conducted. Plasticizing additives with different functional groups, due to which starch modification occurs, were analyzed. In order to expand the spectrum of functional additives for the formation of TPS, the introduction of acids with different amounts of carboxyl groups: citric, oxalic, oleic, stearic was studied. The technological parameters of thermomechanical processing of starch compositions and the quantitative composition of the components are determined. Physical and mechanical tests of strength and elasticity of film samples of TPS compositions and compatible with synthetic polymer were carried out. In order to obtain the structural characteristics of TPS and TPS films with polyethylene, studies were carried out by IR-Fourier spectroscopy and mass spectrometry. Studies of the effect of UV irradiation on the degradability of TPS compositions after exposure in a climate chamber for 90 days were conducted. It was found that the loss of strength and elasticity of TPS and TPS+PE film samples is (82-90)%, elasticity (60-70)%, depending on plasticizing and structure-forming additives and their amounts. [ABSTRACT FROM AUTHOR]

In the present paper the degradation of polyethylene (PE) compositions with additives of 1-5 wt % polyvinyl alcohol (PVA) plasticized with modified rape (MRo) or soybean oil (MSo) was studied. The degradability of obtained composites was evaluated by changes in physico-mechanical characteristics which take place under the influence of UV irradiation and biological factors of the soil during 120 days. It was found that the initial tensile strength of compositions with additives of plasticized polyvinyl alcohol is increased compared with the pure PE by 50-77 % (11,10-13,10 MPa). Meanwhile, after the UV exposure due to the passage of degradation processes, tensile strength was significantly reduced (up to 2-3 MPa). The action of biological soil factors has a little effect on physico-mechanical characteristics, as the result the tensile strength of the samples is reduced by only 15-24 %. The loss of elongation was similarly influenced by UV irradiation and decreased up to 90 % of the original value, which was within 40-80 %. The pyrolysis mass spectrometry was also used to describe the processes which occur during sample aging. It is shown that the functional additives based on plasticized PVA induce the structural transformations were assessed by the change of quantity and intensity of ion fragments. For instance, the intensity of ion fragments for PE-MSo decreased by 7-96 % after the UV exposure and 9-42 % after the aging of composite in the soil. [ABSTRACT FROM AUTHOR]

Thermal mass-spectrometry has been employed to investigate a process of thermal destruction of the polyolefins, modified by degradable additives under the influence of the yeast Yarrrowia lipolytica. It has been determined, that incorporation of amino-containing compound and a polysaccharide leads in increasing of biodegradation of polyolefin compositions under the influence of the above mentioned yeast. [ABSTRACT FROM AUTHOR]