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本文以木素磺酸钙（以下简称木钙）为主要原料，采用引发催化氧化及复配改性法，研制了一种高效减水剂ＧＣＬ。确定了改性工艺条件为，在Ｆｅ２＋＋Ｃｕ２＋引发催化下，以过氧化氢为氧化剂，其用量为木钙的２％～５％，反应温度９０±２℃，反应时间１～２小时，溶液ｐＨ为８～１０，改性剂用量为木钙的２％～５％。实验测定了ＧＣＬ对水泥及混凝土的减水增强性能。结果表明，当ＧＣＬ掺量为０５％时，其净浆减水率达到２０％，３天至２８天的混凝土抗压强度提高了５０％～１６２％，达到了高效减水剂的标准。ＧＣＬ还具有流动度损失小的优点，掺加ＧＣＬ的水泥净浆放置１２０分钟流动度损失仅为２２％，而高效减水剂ＦＤＮ在同一条件下流动度损失却达６２％。初步探讨了ＧＣＬ的表面性能，结果表明，与木素磺酸钙相比，ＧＣＬ的表面性能得到显著改善，溶液的表面张力由４６×１０２Ｎ／ｍ降低到２５×１０２Ｎ／ｍ，并能形成胶束，其临界胶束浓度为１ｇ／ｌ，对水泥颗粒的分散能力提高，同时在水泥颗粒表面上的吸附量增大了３０％。
In this paper, calcium lignin sulfonate (hereinafter referred to as wood calcium) as the main raw material, using the initiation of catalytic oxidation and compound modification method, developed a superplasticizer GCL. The modification process conditions were determined as follows: Hydrogen peroxide was used as the oxidant under the catalysis of Fe2++Cu2+, the amount of wood calcium was 2% to 5%, the reaction temperature was 90±2°C, the reaction time was 1 to 2 hours, and the solution pH was 8 to 10, the amount of modifier is 2% to 5% of wood calcium. Experiments have determined the water-reducing enhancement performance of GCL for cement and concrete. The results showed that when the GCL content was 05%, the water reduction rate of the paste was 20%, and the compressive strength of concrete from 3 days to 28 days increased by 50% to 162%, which met the standard of high-range water reducer. . GCL also has the advantage of a small loss of fluidity. The loss of fluidity of cement paste with GCL is only 22% for 120 minutes, and the loss of fluidity of high-efficiency water-reducing agent FDN is 62% under the same conditions. The surface properties of GCL were preliminarily investigated. The results showed that compared with calcium lignosulfonate, the surface properties of GCL were significantly improved. The surface tension of the solution was reduced from 46×102 N/m to 25×102 N/m. The micelles can be formed with a critical micelle concentration of 1 g/l, which improves the dispersibility of the cement particles and increases the adsorption amount on the surface of the cement particles by 30%.