Page 119 - 《精细化工》2019年第11期
P. 119
第 36 卷第 11 期 精 细 化 工 Vol.36, No.11
2019 年 11 月 FINE CHEMICALS Nov. 2019
医药与日化原料
海藻酸钠/脲醛树脂复合微胶囊的缓释动力学特性
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陈婉毓 ,陈 葵 ,纪利俊 ,盛 勇
(1. 华东理工大学 化工学院,上海 200237;2. 中化云龙有限公司,云南 昆明 655204)
摘要:采用两步法制备海藻酸钠/脲醛树脂复合微胶囊。在树脂化阶段引入海藻酸钠(SA)参与脲醛树脂(UF)
的缩聚反应形成复合壳层,制备了阿维菌素复合微胶囊。通过 FTIR、TG、SEM、粒度分析等表征微胶囊的结
构特征、组成成分、表观形貌、粒度分布。结果表明,SA 的引入可有效改善脲醛树脂微胶囊的团聚现象,提高
药物的包覆率至 60%以上。释放性能研究显示,复合微胶囊的缓释能力较脲醛树脂微胶囊提高,72 d 累计释放
率由 27.5%增至 44.5%,且释放速率受 pH、温度的影响,25 ℃下酸性介质中 27 d 累计释放率超过 50%。释放
行为均可用 Korsmeyer-Pappas 动力学模型进行描述。
关键词:海藻酸钠;脲醛树脂;核壳结构;缓控释;动力学;医药原料
中图分类号:TQ450.6; TB332 文献标识码:A 文章编号:1003-5214 (2019) 11-2267-07
Slow-release Dynamics of Composite Microcapsules of Sodium
Alginate/Urea-formaldehyde Resin
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CHEN Wan-yu , CHEN Kui , JI Li-jun , SHENG Yong
(1. College of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China;
2. Sinochem Yunlong Co., Ltd., Kunming 655204, Yunnan, China)
Abstract: Composite microcapsules of sodium alginate/urea-formaldehyde resin were prepared by two-step
method.Sodium alginate (SA) was introduced to participate in the condensation polymerization of
urea-formaldehyde resin (UF) to form composite shells. Subsequently, abamectin composite microcapsules
were prepared. FTIR, TG, SEM and granulometer were used to characterize the structure, composition,
morphology and particle size distribution of microcapsules. The results show that the introduction of SA
can effectively improve the agglomeration of UF microcapsules and increase the encapsulation efficiency to
more than 60%. In addition, the composite microcapsules have higher release ability than UF microcapsules.
The cumulative release was increased from 27.5% to 44.5% within 72 days. Moreover, the drug release
behavior of modified microcapsules exhibits pH and temperature dependence. The cumulative release of
avermectin was more than 50% within 27 days in acidic medium at 25 ℃. The release behavior can be
described by Korsmeyer-Pappas dynamic model.
Key words: sodium alginatet; urea-formaldehyde resin; core-shell structure; slow/controlled release; dynamics;
drug materials
[1]
农药存在有效利用率低的问题,大量未被利用 度农药低毒化使用 。采用原位聚合法制备的脲醛
的农药通过溶解、渗透、蒸发-沉降等方式进入土壤 树脂(UF)微胶囊具有操作可控、成本低、易于实
[2]
及水环境中,造成资源浪费与环境污染。因此,发 现工业化生产等特点 ,被广泛应用在功能材料 [3-6] 、
[7]
[8]
展环保型农药制剂是大势所趋。其中缓控释微胶囊 胶黏剂 以及农药助剂 等领域。此外,UF 可作为
[9]
制剂因降低农药在环境中的降解而延长了持效期, 潜在氮源,但因降解能力差 ,制约了其在缓控释
可以减少施药次数和剂量,降低环境压力,使高浓 农药领域的应用。以生物多糖类化合物改性 UF,借
收稿日期:2019-03-18; 定用日期:2019-05-05; DOI: 10.13550/j.jxhg.20190205
基金项目:上海市科委项目(18595800900)
作者简介:陈婉毓(1992—),女,硕士生,E-mail:1098302015@qq.com。联系人:陈 葵(1965—),女,副教授,E-mail:
chenkui@ecust.edu.cn。