改性纳米粒子在有机硅类消泡剂中的应用

Nanoparticle Modification and Application in Organic Silicon Defoamer

武俊文 贾文峰 雷 群 熊春明 张建军 李 隽 曹光强 贾 敏

WU Junwen JIA Wenfeng LEI Qun XIONG Chunming ZHANG Jianjun LI Jun CAO Guangqiang JIA Min

为解决纳米 SiO2易团聚和有机硅乳液消泡剂稳定性差、 易分层的问题， 用聚二甲基硅氧烷 （PDMS） 对纳米SiO2表面进行了接枝改性， 考察了反应温度对纳米颗粒接枝率和疏水程度的影响， 研究了纳米颗粒疏水程度及加量对消泡剂消泡、 抑泡性能的影响以及消泡剂的稳定性。结果表明： 反应温度越高， 改性纳米 SiO2的 Zeta电位越高， 疏水性越强， 改性反应的接枝率越高， 反应温度为 65℃时， 改性纳米 SiO2的 Zeta电位最高 （-4 mV）， 颗粒压片的接触角最大 （166.4°）； 纳米 SiO2的疏水程度越高， 消泡剂的消泡和抑泡性能越好； 随纳米 SiO2加量的增大， 消泡剂消泡时间先降低后增加， 抑泡时间先增加后降低， 纳米 SiO2加量为 7%、 颗粒压片接触角为 166.4°时， 消泡剂的消泡、 抑泡效果最佳， 消泡时间为 16 s， 抑泡时间为 88 s。改性纳米 SiO2为主体的消泡剂稳定性较好， 可在去离子水中迅速分散、 液面无油状物， 用去离子水稀释后在 3000 r/min下离心 60 min乳液不分层， 稳定性好于市售有机硅乳液消泡剂。图1表4参14

In order to solve the problem of nano-SiO2 aggregation and the bad stability of organic silicone defoamer with easy layering， polydimethylsiloxane（PDMS）was used to modify the surface of nano-SiO2. The influence of reaction temperature on the grafting rate and hydrophobicity of nanoparticle was investigated. The effect of the hydrophobicity and dosage of nanoparticle on the defoaming and inhibiting foam performance of defoamer， and the stability of defoamer were studied. The results showed that the zeta potential， hydrophobicity and grafting rate of modified nano-SiO2 increased with increasing reaction temperature. When the reaction temperature was 65℃， the zeta potential（-4 mV）and contact angle（166.4°）of nanoparticle reached their highest value. The defoaming and inhibiting property of deformer increased with increasing hydrophobicity of nano-SiO2. With increasing dosage of nano-SiO2， the defoaming time of defoamer decreased first and increased later， and the inhibiting foam time of defoamer increased first and decreased later. When the amount of nano-SiO2 was 7% and the contact angle of nanoparticle tablet was 166.4°， the defoaming and inhibiting foam effect was the best with 16 s defoaming time and 88 s inhibiting foam time. The defoamer which used modified nano-SiO2 as the main body had good stability， could dispersed in deionized water quickly and the liquid level was oil free. The emulsion which was diluted with deionized water didn’ t layered after 60 min centrifugation at 3000 r/min. Its ability was better than that of commercially available silicone emulsion defoamer.

10.19346/j.cnki.1000-4092.2016.04.004