Method for producing a biodegradable polymer composition

Abstract

The subject of the application is a method for producing a biodegradable polymer composition in a twin-screw extrusion process using a granulation extrusion head, characterized in that a low-molecular-weight modifier in the form of urea is introduced into a container in an amount of 0.5% to 10% by weight of the composition and a polymer modifier in the form of a linear aliphatic polyurethane in an amount of 5% to 20% by weight of the composition. A solvent is then introduced into the container in a ratio of low-molecular-weight and polymer modifiers to solvent ranging from 1:20 to 1:60. The low-molecular-weight modifier and polymer modifier in the solvent are then mixed using a high-speed paddle mixer for at least 120 minutes at a rotational speed of 2000 rpm, while simultaneously heating the mixture using a 2000 W resistance heater to a temperature of 25°C to 45°C.Then, a polymer matrix in the form of poly(3-hydroxybutyric acid) is introduced into the solution in an amount of 70% to 94.5% by weight of the composition and the whole is mixed using a mechanical stirrer for 20 minutes at a rotational speed of 500 rpm, after which the mixture is dried in a vacuum dryer at a temperature of 65°C to 90°C under a pressure of 0.09 to 0.10 MPa until a constant mass is obtained.