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Updated: Jun 21, 2026
07:32
Synthesis of Hydrogels with Antifouling Properties As Membranes for Water Purification
Published on: April 7, 2017
Permeation of urea through various polyurethane membranes
Atsushi Watanabe1, Yoshihiro Takebayashi, Toshiro Ohtsubo
1Department of Materials Science, Graduate School of Science and Technology, Nagasaki University, Nagasaki, Japan. watanabea3@sc.sumitomo-chem.co.jp
Pest Management Science
|July 10, 2009
Summary
Polymer membrane properties control urea release rates in agricultural formulations. Increasing urethane and alkyl chain content reduces permeability, offering tunable release profiles for controlled delivery systems.
Area of Science:
- Materials Science
- Polymer Chemistry
- Agricultural Science
Background:
- Controlled-release systems are vital in agriculture for efficient delivery of agents like pesticides.
- Polymer-coated granules are a key formulation, necessitating research into polymer design for varied release patterns.
Purpose of the Study:
- To investigate factors influencing polymer membrane permeability and release rates.
- To compare permeation through plain membranes with release from coated granules.
Main Methods:
- Permeation studies using plain polyurethane membranes.
- Analysis of urea release from polyurethane-coated granules.
- Evaluation of chemical and physical polymer properties.
Main Results:
- Urea permeation decreased with increased urethane and alkyl side chain content in polyurethane membranes.
- Glass transition temperature and crosslink density had minimal impact on permeability.
- Alkyl side chains reduced release rates from coated granules, though capsule expansion led to faster overall release than plain membranes.
Conclusions:
- Chemical properties of polyurethane membranes significantly control urea release rates.
- Physical properties like glass transition temperature and crosslink density are important for assessing release profiles from coated granules.
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