本文選題：醚類聚羧酸減水劑 + 改性聚醚　； 參考：《華南理工大學》2014年碩士論文

【摘要】：相比于傳統(tǒng)的減水劑，聚羧酸系高性能減水劑具有摻量低、減水率高、坍落度損失小、分散性能好、分子結(jié)構(gòu)可設(shè)計性強以及環(huán)保等優(yōu)點，已經(jīng)成為21世紀混凝土減水劑行業(yè)中的研究熱點。目前，聚羧酸系減水劑主要分為酯類PC和醚類PC。與酯類PC相比，醚類PC具有合成工藝簡單、生產(chǎn)周期短、成本較低等優(yōu)點。本論文根據(jù)分子設(shè)計原理，合成了含有羧基、羥基、磺酸基及聚氧乙烯基等官能團的具有梳形分子結(jié)構(gòu)的醚類聚羧酸系減水劑。 本課題采用改性聚醚大單體（TPEG-2400）、馬來酸酐（MA）、甲基丙烯磺酸鈉（SMAS）、丙烯酸羥丙酯（HPA）為主要原料，在引發(fā)劑過硫酸銨（APS）的作用下，采用水溶液自由基共聚合的方法，制得了醚類聚羧酸系減水劑。通過水泥凈漿流動度實驗研究了聚合條件，得到最佳的單體配比為：m（MA）：m（SMAS）：m（HPA）：m（TPEG-2400）=3：2：2：1，引發(fā)劑用量為單體總量的1.5%，，聚合溫度為80℃，反應(yīng)時間為4h。 在最佳合成條件下，對自制的聚羧酸系減水劑進行了一系列水泥凈漿和砂漿試驗。實驗結(jié)果表明，當自制的聚羧酸減水劑摻量為0.5%，水灰比為0.35時，水泥初始的凈漿流動度可達240mm以上，凈漿減水率超過30%，28天的水泥膠砂抗壓強度能夠增加40%，且緩凝效果較好。 采用紅外光譜、核磁共振等儀器對自制的聚羧酸減水劑進行表征。通過測定自制聚羧酸減水劑的表面張力以及與水泥作用時水泥顆粒表面的Zeta電位，研究了聚羧酸減水劑的作用機理。利用XRD與SEM分析水泥漿體的微觀結(jié)構(gòu)，研究了自制聚羧酸減水劑對水泥水化過程的影響。
[Abstract]:Compared with traditional water reducing agents, polycarboxylic acid series high performance water reducers have the advantages of low dosage, high water reducing rate, low slump loss, good dispersion performance, strong design of molecular structure and environmental protection.It has become a research hotspot in the field of concrete water reducing agent in the 21 st century.At present, polycarboxylic acid series water reducers are mainly divided into ester PC and ether PCs.Compared with ester PC, ether PC has the advantages of simple synthesis process, short production cycle and low cost.In this paper, based on the principle of molecular design, ether polycarboxylic acid superplasticizer with comb molecular structure was synthesized with carboxyl, hydroxyl, sulfonic acid and polyoxy vinyl groups.In this paper, the modified polyether macromonomer (TPEG-2400), maleic anhydride (MAA), sodium methallenesulfonate (SMASA) and hydroxypropyl acrylate (HPA) were used as the main raw materials and the initiator, ammonium persulfate (APS), was used to copolymerization with aqueous solution free radical.Ether polycarboxylic acid superplasticizer was prepared.The polymerization conditions were studied by experiments on the fluidity of cement paste. The optimum monomer ratio was: 1% MMA / MMA / MSA / MSA / MPA / TPEG-2400: 3: 2: 2: 1, the amount of initiator was 1.5% of the total amount of monomer, the polymerization temperature was 80 鈩

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