| Abstract [eng] |
The composites of polyethylene and poly(lactic acid) with a different starch additives were obtained by extrusion. In this research the influence of three different additives (native starch, native starch and glycerol mixture and thermopoplastic starch) with their amount of (10 %,20 %, 40 % and 60 %) in the mixture were investigated. In order to research the properties of this biocomposites, they were formed by injection molding. The mass flow rate index showed that composites of poly(lactic acid) are more fluidity than composites of polyethylene and the additive which decreases the mass flow rate index mainly is native starch. According to FT-IR research, the additive is best mixed with plastics when it consists of thermoplastic starch. By increasing the amount of additives, composites transmit the electromagnetic radiation lower. The highest change in transmittance and reflection was obtained using thermoplastic starch. The results of the study of the water drop, contact angle and the water resistance of the composites showed that composites of polyethylene are more hydrophobic than composites of poly(lactic acid). Composites of poly(lactic acid) have higher values of tensile strenght and Young‘s modulus composites of polyethylene. However, composites of polyethylene have bigger elongation break values than composites of poly(lactic acid). In this research was investigated that composites of poly (lactic acid) are more biodegradable than composites of polyethylene, especially when a thermoplastic starch additive was used. |
