含磺酸基和羧基的纤维素衍生物型减水剂的合成与性能研究

Synthesis and Properties of Concrete Water-Reducing Agent of Cellulose Derivatives Containing Carboxyl and Sulfonic acid groups

摘要:

以新疆棉短绒为原料，氨基磺酸、丁二酸酐为酯化剂，采用一锅法合成了磺酸基/羧基纤维素酯(简称：CLCSC)。通过IR、NMR表征了产品结构，GPC测量了产品的重均分子量在2.29× 103 ~1.94× 104范围内。考察了pH对CLCSC溶液黏度性能的影响，并对其用作减水剂的性能和机理进行了初步研究。结果表明：CLCSC取代度最高达到0.92；pH为2~12对不同取代度、不同浓度的CLCSC溶液的黏度影响较小，并且其黏度维持在较低状态，而且当CLCSC掺量为水泥量的1%时，混凝土减水率为28.5%，泌水率为80%，混凝土抗压实验结果表明， CLCSC能在保持相同工作性的条件下起到减水增强作用。因此，CLCSC有望成为具有实际应用价值的混凝土高效减水剂。

Abstract:

A novel method for obtaining cotton linters cellulose sulfonate and carboxylate (CLCSC) using cotton linters cellulose, sulfamic acid, and succinic anhydride by a one-pot synthesis has been developed. The structure of CLCSC was determined by IR and 13CNMR. The molecular weight was measured by GPC (Mw = 2.29× 103 to 1.94× 104). The effect of pH on the solution viscosity was studied. Experimental results showed that the substitution degree up to 0.92. The samples with different DS exhibited good and low viscosity stability from pH 2 to 12. When the proportion of the cement water-reducing agent is 1%, the water reducing ratio can reach 28.5%. The results of application of CLCSC in concrete also indicate that CLCSC can improve the strength of concrete. Thus, CLCSC has the potential to be developed as high-range water-reducing agent.