Slow release of urea through latex film

doi:10.1016/0168-3659(92)90187-V

Journal of Controlled Release

Volume 18, Issue 2, February 1992, Pages 171-180

https://doi.org/10.1016/0168-3659(92)90187-V Get rights and content

Abstract

A systematic analytical and experimental investigation on the slow release of urea from a latex coated urea ball of about 15 mm in diameter into a finite amount of water has been conducted. Seven samples with coating thickness from 0.226 to 0.434 mm were investigated for release time up to 200 days. Experimental results are very well represented by the analytical equations. Diffusivities of latex coated urea balls are found to range between 0.257 × 10⁻⁸ and 2.47 × 10⁻⁸ cm²/s.

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Slow release of urea through latex film

Abstract

J. Pharm. Sci.

J. Pharm. Sci.

Powder Technol.

J. Pharm. Sci.

Polymer coating on urea prills to reduce dissolution rate

J. Agric. Food Chem.