高岭土的球磨疏水改性及其在海藻酸盐凝胶微球中的应用  

Hydrophobic Modification of Kaolin via Ball-Milling Method and Its Application in Alginate Composite Microgel Beads

作　　者：颜慧琼[1] 陈秀琼[1] 朱祺东 李嘉诚[2] 胡德平[1] 张雪琴[1] 戴子豪 林强[1] 

机构地区：[1]海南师范大学化学与化工学院,海南海口571100 [2]海南大学材料与化工学院,海南海口570228

出　　处：《精细化工》2016年第4期383-389,共7页Fine Chemicals

基　　金：国家自然科学基金(21366010;21566009);海南省重点科技计划(ZDXM2014037;ZDXM20120003)~~

摘　　要：为了提高高岭土(KL)对疏水性有机农药的亲和力,以聚甲基氢硅氧烷(PMHS)作为疏水改性剂,采用球磨法改性KL。进而,采用负压冷冻干燥技术将甲氨基阿维菌素苯甲酸盐(EB)负载到改性高岭土颗粒上,然后包覆于海藻酸盐基质中制得载药改性高岭土/海藻酸钙复合凝胶微球(MKL-CA-CMBs)。通过Zeta电位及激光粒度仪、FTIR、SEM、XRD、比表面积及孔径分析仪对改性后KL的结构、形貌和性能进行了表征,同时对MKL-CACMBs的载药和释药性能也进行了考察。结果表明,在球磨机械力作用下,PMHS以物理吸附或化学吸附的方式吸附于KL颗粒表面。改性后的KL粒径减小、比表面积增大,疏水性增强,利于疏水有机农药的负载,使高岭土/海藻酸钙复合凝胶微球(KL-CA-CMBs)的载药率(DLR)和包封率(EE)分别由6.5%和53.1%增长至9.7%和72.5%。MKL-CA-CMBs所具有的缓释性能主要基于MKL对疏水有机农药的亲和能力,剂型的释放模型属于Non-fickian扩散模型。To improve the affinity of kaolin（KL） to hydrophobic organic pesticide,KL was modified by ball-milling method,using poly（methyl hydrosiloxane）（PMHS） as a hydrophobic modifier.Subsequently,immobilization of emamectin benzoate onto the modified kaolin particles was carried out by freeze-drying technology,and then the drug-loaded clays were encapsulated in Alginate matrix to form modified kaolin-calcium alginate composite microgel beads（MKL-CA-CMBs）.The structure,morphology and property of the modified kaolin were characterized by laser particle size and zeta potential analyzer,FTIR,SEM,XRD,specific surface area and pore size analyzer.Simultaneously,the drug-loaded property and release performance of MKL-CA-CMBs were also investigated.Experimental results showed that PMHS was absorbed onto the surface of kaolin via physical adsorption or chemical adsorption under the mechanical action of ball-mill.After the modification of kaolin,its size decreased,specific surface area and hydrophobicity increased,beneficial to the load of hydrophobic organic pesticide,making the drug loading rate（DLR） and encapsulation efficiency（EE） of kaolin-calciumalginate composite microgel beads（KL-CA-CMBs） increased to 9.7% and 72.5% from 6.5% and53.1%,respectively.The slow-release performance of MKL-CA-CMBs was mainly based on the affinity of MKL to hydrophobic organic pesticide,and the release model of the formulation belonged to the Nonfickian diffusion model.

关 键 词：高岭土 球磨法 聚(甲基氢硅氧烷) 疏水改性 海藻酸盐 凝胶微球 缓释性能 功能材料 

分 类 号：TQ235.5[化学工程—有机化工] TQ450.68