木钠接枝磺化三聚氰胺树脂高效减水剂的合成及性能

Synthesis and Properties of Sodium Lignosulfonate Grafting Melamine Resin Based High Range water reducer

摘要:

针对传统的磺化三聚氰胺树脂减水剂（SMF）塌落度损失大、泌水性大的缺陷，以过硫酸铵引发自由基接枝合成了木钠接枝磺化三聚氰胺甲醛树脂高效减水剂（SLMF），获得了优化的合成工艺。红外谱图和SLMF的性能表明木钠成功接枝于SMF结构中。合成的SLMF具有良好的分散性和保水性能。在水灰比为0.29（质量比）时，掺0.6%（质量分数）的SLMF高效减水剂的水泥净浆流动度为253mm，掺SLMF的水泥净浆在90min内的流动度损失从100%降低为61.8%，而静态泌水率从4.84%降低到1.61%。结果表明SLMF高效减水剂能有效克服传统三聚氰胺高效减水剂的缺陷，具有良好的应用前景。

Abstract:

Traditional sulfonated melamine resin (SMF) as high-range water-reducer easily causes a big slump loss and high bleeding ratio of concrete, sodium lignosulfonate grafting melamine resin (SLMF) was synthesized with (NH4)2S2O8 as the radical initiator, and the optimal process variables were obtained. Both of the results of IR and the properties of SLMF showed that sodium lignosulfonate was successfully grafted into SMF. SLMF synthesized under the optimal process variables had good properties of dispersion effect and water retention. When the mass ratio of water to cement was 0.29, the fluidity of cement paste with the addition of 0.6% (mass fraction) of SLMF was 253mm. The fluidity loss within 90 min and the water bleeding ratio within 140min decreased to 61.8% and 1.61% from 100% and 4.84%, respectively. The results indicate that SLMF overcomes the shortages of SMF, and hence exhibits potential application in high-range water-reducer.