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djshaofei

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[交流] 2009年邓春辉Angew chemie的Fe3O4@SiO2@PMMA聚合不需要引发剂么??

百思不得其解呀

前文不赘述了,Fe3O4@SiO2-MPS 已经合成好了
要往上面修饰PMMA了,
The sandwich structured Fe3O4@SiO2@PMMA microspheres were synthesized via an aqueous-phase radical polymerization. Typically, in a three-necked round bottom flask (100 mL) equipped with a mechanical stirrer, a refluxing condenser, and a nitrogen inlet, 10 mL of ethanol dispersion of Fe3O4@SiO2-MPS microspheres were mixed
with 50 mL of aqueous solution containing 5.0 mg of sodium lauryl benzenesulfate under mechanically stirring. After stirring for 1h, 1.0 g of MMA monomers were added, and the resultant dispersion was bubbled with high-purity nitrogen gas for 0.5 h. Then, the flask was immerged into a preheated oil bath at 70oC and the polymerization was carried out with a stirring speed of 200 rpm at 70°C for 24 h. The resulting Fe3O4@SiO2@PMMA microspheres were harvested and washed by magnetic separation.

通了半个小时氮气,往70度水里面一放,就开始聚合了?什么来引发呢?
难道是(MPS,或者十二烷基苯磺酸钠?)

另外半个小时通氮气吹走氧气这个好理解,之后的聚合要不要继续鼓气呢?

不通气的话,岂不是回流冷凝管也要堵上,要不然氧气不是又进来了?
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