硅烷改性聚羧酸减水剂的合成与性能研究  

Synthesis and Properties Research of Silane-modified Polycarboxylate Superplasticizer

作　　者：吴英哲 熊旭峰 简振威 

机构地区：[1]广州市建筑科学研究院集团有限公司,广东广州510440 [2]广州建筑股份有限公司,广东广州510030

出　　处：《混凝土世界》2024年第12期36-40,共5页China Concrete

基　　金：广东省住房和城乡建设厅科技创新计划项目(2022-K 25-212467);广州市建筑集团有限公司科技计划项目([2021]-KJ015、[2022]-KJ013);广州市建筑科学研究院集团有限公司科技计划项目(2022Y-KJ03)。

摘　　要：高性能混凝土中添加硅灰能够显著提升混凝土的力学性能和耐久性能,但是硅灰对聚羧酸减水剂(PCE)的大量吸附严重影响了PCE对水泥的减水分散效果。本文将硅烷偶联剂(VTEO)接枝到聚羧酸减水剂的主链中,合成了一种可有效分散水泥-硅灰的硅烷改性聚羧酸减水剂,并对其结构进行了表征,研究了硅烷改性聚羧酸减水剂对水泥-硅灰浆体分散性能的影响。结果表明:硅烷基团被成功聚合到聚羧酸减水剂分子中,当VTEO取代比例为30%或40%时,对硅灰的分散性能较好;在这2种替代比例下,改性PCE比普通减水剂对硅灰的吸附量分别提升了67.8%和81.5%,表现出较好的吸附分散性能。Incorporating silica fume into high-performance concrete significantly enhances its mechanical properties and durability.However,the substantial adsorption of polycarboxylate superplasticizer(PCE)by silica fume severely impairs the water-reducing and dispersing efficiency of PCE in cementitious systems.This article grafts silane coupling agent(VTEO)into the main chain of polycarboxylate superplasticizer,synthesizes a silane-modified polycarboxylate superplasticizer that can effectively disperse cement silica fume,characterizes its structure,and studied the effect of silane-modified polycarboxylate superplasticizer on the dispersibility of cement silica fume slurry.The results show that silane groups are successfully polymerized into polycarboxylate superplasticizer molecules,and when the VTEO substitution ratio is 30%or 40%,the dispersibility of silica fume is better;under these two substitution ratios,the adsorption capacity of modified PCE on silica fume increases by 67.8%and 81.5%respectively compares to ordinary water reducing agents,demonstrating good adsorption and dispersion performance.

关 键 词：聚羧酸减水剂 硅灰 团聚 硅烷偶联剂 分散性能 

分 类 号：TU528.042.2[建筑科学—建筑技术科学]