| RESEARCH PAPER |
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| Sustained-release Kinetics and Preparation Process Optimization of Chlorpyrifos/Urea-formaldehyde Resin Microcapsules |
| GONG Sheng, SHEN Zhichuan, ZHOU Xinhua, CHEN Huayao, XU Hua
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| College of Chemistry and Chemical Engineering, Zhongkai University of Agriculture and Engineering, Guangzhou 510225 |
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Abstract With people’s increasing awareness of environmental protection and health, low efficiency, large dosage and residual problems caused by widespread use of pesticides were concerned extensively. Pesticide microcapsules has shown lots of benefits to help improve the utilization rate of pesticide and achieve other aims as well. Using urea-formaldehyde resin as wall material and chlorpyrifos (CPS) as core, the chlorpyrifos/urea formaldehyde resin microcapsules (CPS/UFMCs) was fabricated by in-situ polymerization. The effects of emulsifier sorts and dosage, pH, acidification time on particle size and distribution of chlorpyrifos/urea-formaldehyde microcapsules (CPS/UFMCs) were studied, and the optimal process of CPS/UFMCs preparation was obtained. Moreover, the release performance and kinetics of the CPS/UFMCs prepared by optimal process was carried out to further investigate the loading capacity of microcapsules, encapsulation efficiency and release kinetics. The results showed that CPS/UFMCs had a narrow particle size distribution and a small average size with 3wt% sodium dodecyl sulfate(SDS) as emulsifier, the acidification time of 90 min, pH of 2.5, core/wall ratio of 1∶3 and curing temperature of 60 ℃. In addition, the average size of CPS/UFMCs prepared with the optimization process was around 113 μm. Meanwhile, the CPS/UFMCs showed excellent loading performance with more than 62% CPS encapsulated and the CPS loading rate was more than 53%. Moreover, the investigation of release performance showed the chlorpyrifos was released sustainably from the CPS/UFMCs, and more than 90% of the CPS encapsulated was released within 10 days. Subsequently, the release kinetics was analyzed following mathematical models of Korsmeyer-Peppas equation and Higuchi equation. In the kinetic study, the results showed that the release process of CPS/UFMCs followed a Fick diffusion mechanism. Generally, the prepared CPS/UFMCs shows high drug loading, efficient encapsulation and excellent release performance, and can be further developed as a new type of pesticide formulation, which can provide theoretical support and practical reference for the development of new formulations of sustained-release pesticide.
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Published: 11 May 2018
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1 Guo D, Guo H, Zhai Y C. Application of microcapsule technology in coating[J].Journal of Materials and Metallurgy,2005,4(3):206(in Chinese) .
国栋,郭虹,翟玉春.微胶囊技术及其在涂料中的应用[J].材料与冶金学报,2005,4(3):206.
2 Ye M. Study on particles’ coating in forced rotating fluidized bed with spraying[D].Tianjin:Tianjin University,2004(in Chinese).
叶鸣.强制旋流喷雾流化床微粒包衣的实验研究[D].天津:天津大学,2004.
3 Brown E N, Kessler M R, Sottos N R, et al. In situ poly(ureafor-maldehyde) microencapsulation of dicyclopentia-dience[J].Journal of Microencapsulation,2003,20(6):719.
4 Deshpande A A, Shah N H, Rhodes C T, et al. Development of a novel controlled-release system for gastric retention[J].Pharmaceutical Research,1997,14(6):815.
5 Yuan H Z, Li G X, Yang L J, et al. Development of melamine- formaldehyde resin microcapsules withlow formaldehyde emission suited for seed treatment[J].Colloids and Surfaces B:Biointerfaces,2015,128:149.
6 Han L L, Bi L L, Zhao Z D, et al. Adavances in microcapsules pre-paration[J].Biomass Chemical Engineering,2011(3):41(in Chinese).
韩路路,毕良武,赵振东,等.微胶囊的制备方法研究进展[J].生物质化学工程,2011(3):41.
7 Simona C, Veronica A, Pellegrino M,et al. P Urea-formaldehyde microcapsules containing an epoxy resin: Influence of reaction parameters on the encapsulation yield[J].Macromolecules Symposia,2006,234(1):184.
8 Zhang Y, Rocherort D. Characterisation and applications of microcapsules obtained by interfacial polycon-densation[J].Journal of Microencapsulation,2012,29(7):636.
9 Paiva N T, Henriques A, Cruz P, et al. Production of melamine fortified urea-formaldehyde resins with low formaldehyde emission[J].Journal of Applied Polymer Science,2012,124(3):2311.
10 Zhang Y, Rochefort D. Comparison of emulsion and vibration nozzle methods for microencapsulation of laccase and glucose oxidase by interfacial reticulation of poly(ethy-leneimine)[J].Journal of Microencapsulation,2010,27(8):703.
11 Siva T, Sathiyanarayanan S. Self healing coatings containing dual active agentloaded urea formaldehyde (UF) microcapsules[J].Progress in Organic Coatings,2015,82:57.
12 Yang D, Wang N, Yan X, et al. Microencapsulation of seed-coating tebuconazole and its effects on physiology and biochemistry of maize seedlings[J].Colloids and Surfaces B:Biointerfaces,2014,114(2):241.
13 Lin Y S, Zhou X H, Zhou H J, et al. Preparation and low-release performance of chlorpyrifos/feather keratin/sodium alginate microspheres[J].Agrochemicals,2014,53(12):892(in Chinese).
林粤顺,周新华,周红军,等.毒死蜱/羽毛蛋白/海藻酸钠复合微球的制备及其缓释性能[J].农药,2014,53(12):892.
14 Wang L. Preparation of microcapsules by in-situ polymerization of urea-formaldehyde[D].Qingdao:Qingdao University of Science & Technology,2014(in Chinese).
王璐.原位聚合法制备脲醛树脂微囊的处方工艺和筛选[D].青岛:青岛科技大学,2014.
15 Maria P M, Romina O, Vera A, et al. Effect of the preparation method on the structure of linseed oil-filledpoly(urea- formaldehyde) microcapsules[J].Progress in Organic Coatings,2016,97:194.
16 Yoshizawa H, Kamio E, Hirabayashi N, et al. Membrane formation mechanism of cross-linked polyurea microcapsules by phase separation method[J].Journal of Microencapsulation,2004,21(3):241.
17 Yoshizawa H, Kamio E, Kobayashi E, et al. Investigation of alternative compounds to poly(E-MA) as a polymeric surfactant for pre-paration of microcapsules by phase separation method[J].Journal of Microencapsulation,2007,24(40):349.
18 Kage H, Yada N, Kunimasa M, et al. Membrane thickness of microcpasules generated by complex coacervation method[J].Kagaku Kogaku Ronbun,1996,22(2):342.
19 Kage H, Yada N, Kunimasa M, et al. Microencapsulation of mono-dispersed droplets by complex coacervation method and membrane thickness of generated capsules[J].Kagaku Kogaku Ronbun,1997,23(5):365.
20 Despres A,Pizzi A. Colloidal aggregation of aminoplastic polycondensation resins: Urea-formaldehyde versus melamine-formaldehyde andmelamine-urea-formaldehyde resins[J].Journal of Applied Polymer Science,2006,100(2):1406.
21 Fan C J, Zhou X D. Influence of operating conditions on the surface morphology of microcapsules prepared by in situ polymerization[J].Colloids & Surfaces A Physicochemical & Engineering Aspects,2010,363:49.
22 Behzadnasab M, Esfandeh M, Mirabedini S M, et al. Preparation and characterization of linseed oil-filled urea-formaldehyde microcapsules and their effect on mechanical properties of an epoxy-based coating[J].Colloids & Surfaces A Physicochemical & Engineering Aspects,2014,457:16.
23 Zhu L, Long X Y, Wang Z H, et al. Microencapsulation, characte-rization and toxicity evaluation of chlorpyrifos[J].Journal of South China Agricultural University,2010,21(2):40(in Chinese).
朱玲,龙小燕,王正辉,等.毒死蜱的聚脲微胶囊化、表征及毒力评价[J].华南农业大学学报,2010,21(2):40.
24 Korsmeyer R W, Gurny R, Peppas N A, et al. Mechanisms of so-lute release from porous hydrophilic polymers[J].International Journal of Phamaceutics,1983,15(1):25.
25 Lin Y S, Zhou H J, Zhou X H, et al. Preparation and properties of pH-responsive slow-released system of PAA/chlorpyrifos/amino functionalized mesoporous silica[J].CIESC Journal,2016,67(10):4500(in Chinese).
林粤顺,周红军,周新华,等.pH响应性PAA/毒死蜱/氨基化介孔硅缓释体系的制备与性能[J].化工学报,2016,67(10):4500.
26 Dash S, Murthyp N, Nath L, et al. Kinetic modeling on drug release from controlled drug delivery systems[J].Acta Poloniae Pharmaceutica-Drug Research,2010,67(3):217.
27 Siepmann J,Siepmann F. Mathematical modeling of drug delivery[J].International Journal of Pharmaceutics,2008,364(2):328. |
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2018, Vol. 32 
