Preparation and properties of stover cellulose grafted poly (acrylic acid‐potassium humate) with water‐retention and slow‐release fertilizer

Abstract

AbstractTo improve the utilization of stover and fertilizer and also save water resources, a degradable slow‐release fertilizer of corn stover cellulose graft poly (acrylic acid‐potassium humate) (CSC‐g‐P(AA‐KHA)) was prepared using corn stover cellulose (CSC), acrylic acid (AA) and potassium humate (KHA) by aqueous solution polymerization. Characterization of CSC‐g‐P(AA‐KHA) with Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and thermogravimetric analysis (TGA) techniques provided evidence for the successful preparation. The product prepared exhibited excellent water absorbency (792.89 g·g−1 and 72.69 g·g−1 in deionized water and 0.9 wt% NaCl solution, respectively) and enhanced soil's capacity of water holding and water retention. After 5 cycles, the water absorptivities of CSC‐g‐P(AA‐KHA) in deionized water and 0.9 wt% NaCl solution were 51.71% and 49.97% of their initial water absorption, respectively. The degradation rate of CSC‐g‐P(AA‐KHA) was 32.02% after 50 days. Soil column leaching test and pot experiment demonstrated the slow‐release effect and plant growth promotion of CSC‐g‐P(AA‐KHA). CSC‐g‐P(AA‐KHA) showed desirable application potential in agriculture and is expected to become a functional fertilizer that integrates water absorbing, water‐holding and slow‐release properties.