Plasma-modified biodegradable coatings for controlled nitrogen release from urea

Area of Science:

• Agricultural Science
• Materials Science
• Environmental Science

Background:

• Conventional urea formulations lead to rapid nitrogen loss and environmental issues.
• Biodegradable polymers offer a sustainable alternative for controlled nutrient release.
• Developing advanced urea coatings is crucial for efficient and eco-friendly agriculture.

Purpose of the Study:

• To develop and evaluate novel biodegradable polymer-coated urea using polybutylene succinate (PBS), polycaprolactone (PCL), and methylene diphenyl diisocyanate (MDI).
• To assess the impact of plasma surface treatment on the properties and nitrogen release dynamics of the coated urea.
• To investigate the potential of these formulations for environmentally responsible nutrient management.

Main Methods:

• Urea was coated with a blend of PBS and PCL, crosslinked with MDI, and subjected to plasma surface treatment.
• Fourier Transform Infrared Spectroscopy (FT-IR) and X-ray diffraction (XRD) were used to analyze structural modifications.
• A 90-day soil column experiment evaluated nitrogen release dynamics (nitrate-nitrogen and total nitrogen).

Main Results:

• MDI crosslinking and plasma treatment reduced PCL crystallinity, indicating enhanced polymer interactions.
• All coated urea formulations significantly delayed the peak release of nitrate-nitrogen (NO3--N) from 30 days to approximately 70 days.
• At 90 days, cumulative NO3--N release was reduced compared to the control, with the MDS (PBS+PCL+MDI+Plasma) treatment showing sustained release.

Conclusions:

• Plasma-modified biodegradable polymer-coated urea provides prolonged and tunable nitrogen release.
• These formulations represent a promising approach for environmentally responsible nutrient management.
• The study highlights the potential to mitigate nitrogen loss and enhance nutrient use efficiency in agriculture.