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xwzeng2006

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[求助] 请大家按文献帮我设计一下实验(缩聚反应)

大家有做过缩聚反应的吗?是不是在三口瓶中机械搅拌,另一个口抽真空。这样加热反应啊。我想问一下抽真空是用水泵还是油泵,能用磁力搅拌吗?用磁力搅拌怕搅不动,就是粘度大了,机械搅拌抽真空不是很好操作啊。请大家帮帮我,谢谢!

85% DL-lactic acid solution (40.0 mL, 0.378 mol of lactic acid) were poured into
a 100 mL round flask. After three rounds of nitrogen replacement, this solution was
gradually heated to 140 C under reduced pressure for 8 h to remove the water
produced. DL-malic acid (20.0 g, 0.149 mmol)was then added to the obtained viscous oligomer of poly(DL-lactic acid) under nitrogen protection. This system was maintained at 140 C with constant stirring under reduced pressure for another 24 h. The resulting PLMAwas dissolved in tetrahydrofuran (THF), and precipitated with a large amount of ethyl ether, and then dried under vacuum.
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xwzeng2006

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请大家帮帮我啊,谢谢
2楼2012-06-11 19:54:12
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xwzeng2006

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不知道这样蒸水会不会把聚合物也蒸出来!
4楼2012-06-12 15:22:48
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