Film-Forming Starch Composites for Agricultural Applications

Biodegradable polymer composites were prepared from starch, crude glycerol, rapeseed cake and urea. The uniform films of the composites were prepared by casting technique. Mechanical properties and solubility in water of the films were studied. Increase of the content of rapeseed cake in the composites lead to the decrease of tensile strength and to the increase of elongation at break. The solubility of the composites in water increased with the increase of the content of rapeseed cake and urea. The changes of pH of soil being in the contact with the composite films were studied. It was established that the composites with the ratio of starch, rapeseed cake, crude glycerol and urea ranging from 4:6:3:0.2 to 4:6:3:1 can be used for the production of disposable plant pots. Too high content of urea can increase pH of soil up to the limit dangerous for plants.