Biocomposites as coatings for slow nutrients release from fertilisers
The unbalanced release of fertilisers influences the availability of nutrients in soil, and their leaching affects the ground water sources. Therefore, the coating of water-soluble fertilisers is considered as the main approach that improves their uses.
Encapsulated diammonium phosphate granules
Now a biodegradable coating based on polylactic acid (PLA) and cellulose acetate (CA) was proposed to encapsulate diammonium phosphate (DAP) granules using a rotary pan. The blends were prepared by vigorous mixing of PLA and CA in a solvent mixture using a homogeniser equipment and the prepared films of homopolymers and their blends were fully characterised. Moreover, the coating thicknesses were controlled by adjusting the duration of the coating process.
The delaying performance of the coatings meet the release rate required by the European standard (20 % in the first 24 h). The introduction of CA decreases the PLA crystallinity and therefore accelerates the degradation of the coating in soil.
The study has been published in Progress in Organic Coatings, Volume 156, July 2021.