疏水改性羟乙基纤维素缔合增稠机理研究

Study of Thickening Mechanism of Hydrophobicly Modified Hydroxyethyl Cellulose Solutions

疏水改性羟乙基纤维素(HMHEC)通过疏水缔合与水分子有较强的相互作用,从而表现出显著的增稠增黏性、耐温耐盐性和抗剪切稳定性,作为黏度控制剂、涂料添加剂、石油开采助剂具有广泛的应用前景。今研究了HMHEC对颜料粒子CaCO3和高岭土的吸附作用机理,实验发现HMHEC对颜料粒子的吸附量随HMHEC的浓度的增大而增大,随温度和颜料粒子浓度的升高而减少;通过激光粒度仪、Zeta电位仪等测试考察了HMHEC与颜料粒子吸附前后粒径以及Zeta电位的变化情况,发现了HMHEC与颜料粒子之间的相互作用除了范德华力,氢键力和静电力以外,疏水缔合作用力也起到了非常重要的作用;最后比较了HMHEC对不同类型颜料粒子的作用机理以及解释了其在涂料中的缔合增稠机理。

The hydrophobicly modified hydroxyethyl cellulose （HMHEC） has high-performances of obviously increased viscosity, high temperature and salt resistances and anti-shearing stableness; all of those are because of the relatively strong interaction between the hydrophobic association and hydration. Accordingly, the HMHEC has a bright prospect of to be used as viscosity control agent, coating additive or oil exploitation additive. The mechanism of HMHEC adsorbing pigment particles, such as CaCO3 and kaolin, was studied in this paper, and the experimental results show that the amount of pigment particles adsorbed by HMHEC increases with the increase of HMHEC concentration and decreases with the increases of the temperature and pigment particle concentration. The change of the particle size and Zeta potential in the adsorption process were measured and investigated by laser particle analyzer and Zeta potential analyzer. It was found that, besides Van der Waai＇s force, hydrogen bond and electrostatic force, hydrophobic association also plays an important role in the process of HMHEC adsorbing pigment particles. In addition, the mechanisms of processes that HMHEC absorbs different types of pigments were compared, and the thickening mechanism of HMHEC in the coating was explained.