非均相聚合反应中乳化剂用量及搅拌状况对粒径大小的影响

Influences of the using amount of emulsifier and stirring condition on the particle size in heterogeneous polymerization system

以釜径为74mm,无挡板的玻璃搅拌釜为反应釜,恒温水浴为热源;自来水为冷却水组成了一套冷模的聚合反应实验装置,同时采用蜂蜡为分散相,去离子水为连续相,Span-80及Tween-60为乳化剂,以二叶平桨、二叶斜桨直边、二叶斜桨圆边及三叶后掠式搅拌桨叶为基准,分别研究了乳化剂用量及不同搅拌状况对粒径大小的影响。结果表明:在低转速下,三叶后掠式搅拌桨的搅拌效果最好;在一定范围内,同一转速下的树脂的平均粒径随乳化剂用量的增加而减小。

A cold model experimental polymerization unit was composed of a glass agitated polymer of 74 mm diameter without baffles,thermostat water bath as heat source,and tap water as cooling water.In the above unit equipped with a two-flat-blade paddle type agitator,a two-blade straight-edge inclined paddle type agitator,a two-blade round-edge inclined paddle type agitator,a three-blade sweepback agitator respectively,the influences of the amount of emulsifier and stirring condition on particle size were studied under the conditions of beeswax as dispersed phase,deionized water as continuous phase,and span-80 and Tween-60 as emulsifier.The results showed that the best stirring effect was obtained with a three-blade sweepback type agitator at low rotating rate,and that the average particle size of resins obtained at the same rotating rate decreased with the increase of the using amount of emulsifier within some ranges.