A METHOD FOR MANUFACTURING BIODEGRADABLE PACKAGING MATERIAL, BIODEGRADABLE PACKAGING MATERIAL AND A PACKAGE OR A CONTAINER MADE THEREOF
The invention provides a biodegradable packaging materi- al, a method of manufacturing the same, as well as products made of the material. The manufacture comprises extrusion onto a fibrous substrate (1) one or more polymer coating layers including at least one layer (2) of a polymer blend consisting of (i) 20–95 wt-% of polylactide having a high melt index of more than 35 g/10 min (210 °C; 2.16 kg), (ii) 5–80 wt-% of polybutylene succinate (PBS) or a biodegradable derivate thereof, and (iii) 0–5 wt-% of one or more polymeric additives. The components of the blend are melted and blended in connection with the extrusion step. The goal is to improve extrudability, increase ma- chine speed in extrusion and maintaining good adhesive- ness to the substrate and good heat-sealability of the coat- ing. The products include disposable drinking cups and board trays, as well as sealed carton packages for solids and liquids.