壳聚糖喷雾干燥微胶囊和微球作为可膨胀控制释放材料的肥料载体。

Chitosan spray-dried microcapsule and microsphere as fertilizer host for swellable - controlled release materials.

机构信息

Laboratory of Polymeric Materials and Biosorbents, Federal University of São Carlos, UFSCar, 13600970, Araras, SP, Brazil; Graduate Program in Materials Science and Engineering, University of Sao Paulo, USP- FZEA, 13635900, Pirassununga, SP, Brazil.

Laboratory of Polymeric Materials and Biosorbents, Federal University of São Carlos, UFSCar, 13600970, Araras, SP, Brazil; Research Group on Water, Soil and Environment Engineering, Federal University of São Carlos, UFSCar, 13600970, Araras, SP, Brazil.

出版信息

Carbohydr Polym. 2018 Sep 15;196:47-55. doi: 10.1016/j.carbpol.2018.05.014. Epub 2018 May 6.

DOI:10.1016/j.carbpol.2018.05.014

PMID:29891320

Abstract

A fertilizer delivery system based on chitosan (Ch) or chitosan/montmorillonite clay (Ch/MMt) was developed by spray drying technique using 2-fluid (2FN) and 3-fluid (3FN) nozzles. 2FN provided solid microspheres and 3FN formed microcapsules structures. Morphology is dependent upon formulation and the type of nozzle used. As higher the number of the components (polymer, clay and sodium tripolyphosphate (TPP)) in the microparticles more collapsed and non-shaped spheres are generated. Different structures provided distinct nutrient releasing profiles. Higher swelling values (∼500%) and slower fertilizer releasing process (under 70% in the firsts measurements) are observed for microcapsules. This phenomenon occurs due to entrapped nutrient by an extra chitosan outer layer. The swelling-controlled release mechanism was observed for both microcapsules and microspheres instead of diffusion-controlled. Swelling characteristic was confirmed in soil medium since after water irrigation higher fertilizer releases were observed.

摘要

采用 2 流体（2FN）和 3 流体（3FN）喷嘴通过喷雾干燥技术开发了基于壳聚糖（Ch）或壳聚糖/蒙脱土粘土（Ch/MMt）的肥料输送系统。2FN 提供固体微球，3FN 形成微胶囊结构。形态取决于配方和使用的喷嘴类型。在微颗粒中，聚合物、粘土和三聚磷酸钠（TPP）等成分的数量越多，生成的塌陷和非成型球体就越多。不同的结构提供了不同的养分释放曲线。微胶囊的溶胀值较高（约 500%），肥料释放过程较慢（最初测量中不到 70%）。这是由于额外的壳聚糖外层困住了养分。观察到微胶囊和微球都具有溶胀控制释放机制，而不是扩散控制。在土壤介质中确认了溶胀特性，因为灌溉水后会释放出更多的肥料。