Characterization of mechanical and thermal properties of PLA/blowing agents composites

Biodegradable plastics find more and more applications. In addition to biodegradable packaging, the number and type of products also being used in medical applications is increasing. The goal of the presented research is development technique for preparation of microcellular foams based on biodegradable polylactic acid (PLA) and its co-polymers for biomedical applications. The goal is to understand the influence of microblowing agents on the course and efficiency of microcellular process of injection molding biodegradable polymer compounds as well as on the properties of the obtained products. Polylactide (PLA) under the trade name NatureWorks Ingeo 2002D modified with chemical blowing agents having an exothermic and endothermic character of the distribution was used during the tests. The blowing agents used in the injection molding process were inserted into polymers processed in the following amounts: 0.5%, 1.5% and 3.0% wt. The article presents the characteristics of the process of injection of biodegradable plastics and the study of selected physical properties of the materials produced. The research on the structure of manufactured materials, density and the degree of porosity, mechanical strength, impact resistance and hardness are presented. It was found that as a result of the increased temperature in the plasticizing system, the blowing agents decompose and the resulting numerous microcells, due to pressure and surface development, immediately mix with the plastic. The resulting microcells are filled with both air and gases, increasing the volume of PLA. There was a change in the examined physical properties of the tested materials, mainly mechanical strength of the tested PLA compositions.