Preparation and properties of hexaconazole microcapsule suspension concentrate
In order to solve the problems of short persistence,low utilization efficiency,high residue lev-els,and certain toxicity to target crops and non-target organisms during the use of hexaconazole,four kinds of hexaconazole polyurea microcapsules with different shell structures were prepared via interfacial polymerization using isophorone diisocyanate(IPDI)as the wall material and a mixture of triethylenetet-ramine(TETA)and TETA with ethylenediamine(EDA),piperazine(PIP),and lysine(LYS)as the curing agents.The prepared microcapsules were characterized using dynamic light scattering,infrared spectroscopy,and scanning electron microscopy.The results showed that the microcapsules had a spheri-cal shape with a uniform particle size distribution,an average particle size of approximately 2 μm,encap-sulation efficiency ranging from 89％to 97％,and drug loading ranging from 65％to 76％.The release behaviors of the four different microcapsules were investigated,and the cumulative release rate in metha-nol solution ranged from 29％to 65％after 30 hours,indicating good sustained-release properties.The sustained release rate and cumulative release amount decreased with increasing crosslinking degree and chain segment rigidity of the microcapsule wall,suggesting that the release behavior of the microcapsules can be controlled by regulating the chain segment structure of the wall.The microcapsules prepared using interfacial polymerization had a uniform particle size distribution,high encapsulation efficiency,strong drug loading capacity,and good sustained-release properties,and the synthesis process was simple as well as the reaction conditions were mild,which could provide a reference for the development of hexaconazole microcapsule formulations.
万方数据
维普
