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xwzeng2006銀蟲(chóng) (著名寫(xiě)手)
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[求助]
請(qǐng)大家按文獻(xiàn)幫我設(shè)計(jì)一下實(shí)驗(yàn)(縮聚反應(yīng))
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大家有做過(guò)縮聚反應(yīng)的嗎?是不是在三口瓶中機(jī)械攪拌,另一個(gè)口抽真空。這樣加熱反應(yīng)啊。我想問(wèn)一下抽真空是用水泵還是油泵,能用磁力攪拌嗎?用磁力攪拌怕攪不動(dòng),就是粘度大了,機(jī)械攪拌抽真空不是很好操作啊。請(qǐng)大家?guī)蛶臀,謝謝! 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. |
木蟲(chóng) (正式寫(xiě)手)
銀蟲(chóng) (著名寫(xiě)手)
金蟲(chóng) (小有名氣)

銀蟲(chóng) (著名寫(xiě)手)
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