纤维素醚改性水泥浆的粘度变化研究

Study on Viscosity Variation of Cement Pastes Modified by Cellulose Ethers

增稠是纤维素醚对水泥基材料的重要改性效果。研究了纤维素醚掺量、粘度仪旋转速度和温度对纤维素醚改性水泥浆粘度变化的影响。结果表明:纤维素醚掺量增加,水泥浆的粘度不断增加,纤维素醚溶液和水泥浆的粘度具有"复合叠加效应";纤维素醚改性水泥浆的假塑性低于纯水泥浆,粘度仪的旋转速度越低,或纤维素醚改性水泥浆的粘度越低,或纤维素醚掺量越低,纤维素醚改性水泥浆的假塑性越明显;温度升高,由于温度和水泥水化的共同作用,纤维素醚改性水泥浆的粘度会增加或降低。纤维素醚的种类不同,其改性水泥浆的粘度变化规律存在差异。

Thickening is the important modification effect of cellulose ethers on cement-based materials. This paper investigated the effect of cellulose ethers dosage, rotating speed of viscometer and temperature on the viscosity variation of cellulose ether-contained cement pastes. The results showed that the viscosity of cement pastes increased with the increase of cellulose ethers dosage. The viscosity of cellulose ethers solutions and cement pastes had the compound superposition effect. The pseudoplasticity of cellulose ether-contained cement pastes was weaker than that of neat cement pastes. The lower the rotating speed of viscometer, the lower the viscosity of cellulose ether-contained ce- ment pastes, or the lower the cellulose ethers dosage, the stronger the pseudoplasticity of cement pastes modified by cellulose ethers was. The viscosity of cellulose ether-contained cement pastes increased or decreased with the increase of temperature due to the cooperative action of temperature and cement hydration. The viscosity variation law of cellulose ether-contained cement pastes differed by changing the variety of cellulose ether.