原位聚合法制备草甘膦微胶囊

采用原位聚合法制备以脲醛树脂为壁材的草甘膦微胶囊除草剂。探讨了缩聚反应条件对微胶囊粒径及其分布和微胶囊结构的影响,并考察了微胶囊的包封率和缓释性能。结果表明,以氯化铵为酸性催化剂,酸化时间为4 h,终点pH2.0,固化温度70℃,固化时间2 h,搅拌速度2 000 r.min-1,乳化剂采用苯乙烯-马来酸酐（SMA）,可制得包封率为91.9%,粒径分布均匀且粒径1~10μm的流动性球型固体微胶囊。以上结果及应用试验均显示该微胶囊能够满足实际需要。

Making glyphosate microcapsules by in-situ polymerization

Microcapsules of glyphosate were made by the method of in-situ polymerization with urea- formaldehyde resin as the outer membrane. The effects of reaction parameters on particle size, distribution and structure were studied. Encapsulation efficiency and controlled release were characterized. Optimal reaction conditions were as follows ： acidification time being 4 h, endpoint pH being 2.0, curing temperature being 70 , curing time being 2 h, mixing rate being 2 000 r · min-1, acid catalyst being NH4 Cl and suitable emulsion being styrene maleic anhydride （SMA）. Under those conditions, solid, spherical microcapsules were formed with decentralization of 1 -10 μ m, the encapsulation efficiency was 91.9% and it had excellent controlled release properties. These results suggested that the microcapsules could fully meet the needs of practical applications. [ Ch, 4 fig. 2 tab. 9 ref. ]