文献类型：期刊文献

英文题名：Effects of process parameters on the physical properties of poly (urea-formaldehyde) microcapsules prepared by a one-step method

作者：Fan Chuanjie[1];Tang Juntao[1];Zhou Xiaodong[1]

机构：[1]E China Univ Sci & Technol, State Key Lab Chem Engn, Shanghai 200237, Peoples R China

年份：2013

卷号：22

期号：9

起止页码：665

外文期刊名：IRANIAN POLYMER JOURNAL

收录：;EI(收录号：20133116563718);WOS:【SCI-EXPANDED(收录号:WOS:000321868200004)】；

语种：英文

外文关键词：Microcapsule; Poly (urea-formaldehyde); One-step method; Processing parameters

摘要：The physical properties of microcapsules are strongly influenced by the synthetic conditions used for their preparation. To prepare microcapsules possessing a smooth surface morphology, high mechanical strength, and reduced permeability of the core material, in situ polymerization in an oil-in-water emulsion was performed using poly (urea-formaldehyde) and tetrachloroethylene as the shell and core materials, respectively. The influence of the synthetic conditions, including the initial pH value, concentration of wall material, concentration of NaCl, and heating rate, on the properties of the resulting microcapsules was investigated systematically by an orthogonal factorial design. The physical properties of the microcapsules were characterized using scanning electron microscopy and optical-photographic microscopy. The results showed that the concentration of shell material has a substantial effect on the mechanical strength of the microcapsules. Additionally, a slow heating rate and high initial pH value enhance the preparation of well-defined spherical microcapsules having excellent barrier properties. Finally, a moderate concentration of sodium chloride can remarkably improve the compactness of the capsule wall. The optimum conditions, determined on the basis of utilization of wall material, are as follows: initial pH value: 3.5; concentration of shell material: 3.6 x 10(-2) g/mL; heating rate: 0.5 A degrees C/min; and concentration of sodium chloride: 5.0 x 10(-2) g/mL.