【pH响应缓释控肥】Zhi-yuan Ma † Xin Jia *† Guo-xiang Zhang † Jia-mei Hu † Xiu-lan Zhang † Zhi-yong Liu † He-yun Wang † and Feng Zhou ‡. pH-Responsive Controlled-Release Fertilizer with Water Retention via Atom Transfer Radical Polymerization of Acrylic Acid on Mussel-Inspired Initiator. J. Agric. Food Chem. 2013 61 (23) pp 5474–5482

Abstract

This work reports a polydopamine-graft-poly(acrylic acid) (Pdop-g-PAA)-coated controlled-release multi-element compound fertilizer with water-retention function by a combination of mussel-inspired chemistry and surface-initiated atom transfer radical polymerization (SI-ATRP) techniques for the first time. The morphology and composition of the products were characterized by transmission electron microscopy (TEM) Fourier transform infrared (FTIR) spectroscopy thermogravimetric analysis (TGA) gel permeation chromatography (GPC) and inductively coupled plasma (ICP) emission spectrometry. The results revealed that the stimuli-responsive layer formed by a Pdop inner layer and a PAA outer corona exhibit outstanding selective permeability to charged nutrients and the release rate of encapsulated elements can be tailored by the pH values. At low pH the Pdop-g-PAA layer can reduce nutrient loss and at high pH the coating restrains transportation of negative nutrients but favors the release of cations. Moreover PAA brushes provide good water-retention property. This Pdop-graft-polymer brushes coating will be effective and promising in the research and development of multi-functional controlled-release fertilizer.

【利用旋转转取土壤样品的评估】Carrie R. Levine Ruth D. Yanai Matthew A. Vadeboncoeur Steven P. Hamburg April M. Melvin Christine L. Goodale Benjamin