Synthesis and delayed germination of vinyl acetate-butyl acrylate copolymer for coating of sugar beet seeds using combined experimental design and image analysis

Seeds are coated widely with different polymers for increasing productivity and improving stand establishment of different crops. Emulsion copolymerization of vinyl acetate and butyl acrylate can be used for sugar beet seed coating. In this study, for the first time, a fractional factorial design, as an statistical experimental design method, was combined with image analysis method to achieve the optimal condition for emulsion copolymerization of vinyl acetate (VAc) and butyl acrylate (BuA) as a delayed-germination copolymer. The optimum condition was on the time of 3.16 hours, the temperature of 65˚C, the initiator concentration and anionic surfactant of 0.0121 wt%.The synthesized copolymer was homogeneous and was characterized using ATR-Fourier transform infrared spectroscopy (ATR-FTIR), Differential Scanning Calorimetry (DSC), Particle Size Distribution (PSD) and Scanning Electron Microscope (SEM) analysis. Then the synthesized copolymer was used for coating of sugar beet seeds. The results show that the synthesized copolymer does not have adverse interaction with pesticides, fungicides and the color, which used for seed coating. Therefore, it can be used in coating of sugar beet seeds. Also, the synthesized copolymer delayed germination about 40 days.