a School of Chemical Engineering , East China University of Science and Technology , Shanghai , China.
J Microencapsul. 2019 Jan;36(1):62-71. doi: 10.1080/02652048.2019.1599075. Epub 2019 Apr 15.
Polyurethane modified with polylactic acid microcapsules were fabricated for controlled release of chlorpyrifos (one of the high usage solid phosphorous insecticides) via interfacial polymerisation with diphenylmethane diisocyanate, polyether triol, 1,4-butanediol and polylactic acid as modifier. The structure, morphology and release properties of synthesised microcapsules were characterised by Fourier transform infra-red spectroscopy, thermogravimetric analyser, scanning electron microscope, particle size analyser and high-performance liquid chromatography. More benign solvents, namely ethyl acetate and n-butyl acetate were used as replacement for toxic solvents commonly used in the preparation of polyurethane microcapsules, namely xylene. The spherical microcapsules prepared in this study were 1-20 μm in diameter. Fourier transform infra-red spectroscopy indicated that polylactic acid had successfully participated in the interfacial polymerisation of polyurethane. Encapsulation efficiency of microcapsules can amount up to 71.0% w/w with a loading efficiency of 26.2% w/w. The microcapsules exhibited a sustained release period above 60 days. Combining polylactic acid into the soft segment of polyurethane proves to effectively accelerate the release rate.
采用界面聚合法，以二苯基甲烷二异氰酸酯、聚醚三醇、1,4-丁二醇和聚乳酸为改性剂，合成了聚乳酸改性的聚氨酯微胶囊，用于氯吡磷（高用量的固体有机磷杀虫剂之一）的控制释放。通过傅里叶变换红外光谱、热重分析仪、扫描电子显微镜、粒径分析仪和高效液相色谱对合成微胶囊的结构、形态和释放性能进行了表征。采用乙酸乙酯和正丁酯替代了通常用于制备聚氨酯微胶囊的有毒溶剂，如二甲苯。本研究中制备的球形微胶囊直径为 1-20μm。傅里叶变换红外光谱表明，聚乳酸已成功参与了聚氨酯的界面聚合。微胶囊的包封效率可达 71.0%（w/w），载药效率可达 26.2%（w/w）。微胶囊的释放期超过 60 天。将聚乳酸结合到聚氨酯的软段中，可以有效提高释放速率。
