引用本文摘 要：對四種聚羧酸系高性能減水劑進行了擴鏈劑改性研究，并優化出最佳改性工藝。結果表明，改性后的聚羧酸系高性能減水劑A對水泥的分散性能僅起到抵消緩釋作用，B、C、D對水泥的分散性能有很大的提高，尤其是對保坍性能較差的減水劑；改性后的減水劑對混凝土的流變性能與水泥凈漿流動度的變化規律基本一致，對混凝土的含氣量、抗壓強度、滲透性能和外觀質量有了明顯改善，而且降低了成本；同時，從分子鏈結構搭配的角度分析了擴鏈劑的改性機理。 Abstract: Four kinds of polycarboxylic high performance water reducer were modified by chain extender, and the best modification technology was optimized. The results show that the modified polycarboxylic high performance water reducer A only plays release effect on the dispersiveness of cement, while the modified polycarboxylic high performance water reducer B, C and D can greatly improve the dispersiveness of the cement, especially to the water reducer with poor slump performance. Furthermore, the influence of the modified water reducer on rheological properties of concrete has the same rule as that of the modified water reducer on the fluidity of cement paste. In addition, gas content, compressive strength, permeability and appearance quality of the concrete are obviously improved and the cost is also reduced. Finally, the modification mechanism of chain extender is analyzed from the point of the molecular chain structure.