醇基涂料中常用悬浮剂流变特性的研究

Rheological Properties of Common Suspending Agents in Alcohol-Based Coatings

研究了三种悬浮剂制成的乙醇悬浮液的流变与触变规律,发现用二甲苯和120#溶剂油引发后制得的有机膨润土乙醇悬浮液呈现塑性流体的基本特征,形成了较小的触变环,屈服值和同等剪切速率下的剪切应力随引发剂比例的增加而增加。在有机膨润土与引发剂之比为1∶10的情况下,屈服值和同等剪切速率下的剪切应力随有机膨润土浓度的增加而增加。浓度为12.0%、13.0%和14.0%的锂基膨润土乙醇悬浮液也呈现塑性流体的基本特征,形成了较小的触变环。屈服值和同等剪切速率下的剪切应力随锂基膨润土浓度的增加而增加。凹凸棒土浓度为11.0%、11.5%和12.0%的乙醇悬浮液呈现带屈服值假塑性流体特征,随着凹凸棒土浓度的升高,悬浮液屈服值变大,同等剪切速度下的剪切应力升高,在进行触变环测试时呈现逆时针方向封闭的特征。

The rheological and thixotropic laws of ethanol suspension made from three suspending agents were studied. It was found that the organic bentonite ethanol suspension prepared with xylene and 120~# solvent naphtha presented the basic characteristics of a shaping fluid, with a smaller thixotropic ring, and the yield value and shear stress at the same shear rate increased with an increase in the initiator ratio. When the ratio of organobentonite to initiator was 1:10, the yield value and shear stress at the same shear rate increased with increasing organobentonite concentration. The ethanol suspensions of lithium bentonite with the concentrations of 12.0%, 13.0% and 14.0% also exhibited the basic characteristics of plastic fluids, forming smaller thixotropic rings. The yield value and the shear stress at the same shear rate increased with increasing the lithium-based bentonite concentration. Ethanol suspensions with attapulgite concentrations of 11.0%, 11.5%, and 12.0% exhibited the characteristics of pseudo-shaped fluids with yield values. As the concentration of attapulgite increased, the yield value of the suspension became larger, the shear stress increased, and the thixotropic ring test showed a closed feature in a counterclockwise direction.