本文選題：四臂 + 聚羧酸高效減水劑�。� 參考：《濟南大學》2017年碩士論文

【摘要】：目前建筑施工技術(shù)的發(fā)展十分迅速,對所使用的混凝土的性能要求提高,相應的對減水劑的性能要求就會更高,傳統(tǒng)梳形聚羧酸減水劑逐漸不能適用、滿足高性能混凝土的要求。而且傳統(tǒng)梳形聚羧酸減水劑為無規(guī)共聚物,分子結(jié)構(gòu)不明確,無法從本質(zhì)上揭示結(jié)構(gòu)與性能的關(guān)系。因此,本課題利用原子轉(zhuǎn)移自由基聚合合成結(jié)構(gòu)明確的四臂AB型雙嵌段聚羧酸減水劑FAPC,以彌補梳形聚羧酸減水劑存在的不足。本課題以季戊四醇(Pentaerythritol,PET)為核,丙烯酸叔丁酯(tert-Butyl acrylate,tBA)、異戊烯醇聚氧乙烯醚(TPEG)為單體,N,N,N',N,'N''-五甲基二亞乙基三胺(Pentamethyldiethylenetriamine,PMDETA)為配體,溴化亞銅(CuBr)為催化劑,利用原子轉(zhuǎn)移自由基聚合(ATRP),合成四臂AB型雙嵌段聚羧酸減水劑FAPC。得到的最佳實驗條件為:各物質(zhì)的配比為,n(PET):n(BIBB):n(t BA):n(TPEG)=1:4.2:143:25,n(引發(fā)劑):n(CuBr):n(PMDETA)=1:4:8;其他實驗條件:(1)制備小分子引發(fā)劑:在冰水浴(0℃)下,向季戊四醇(PET)中滴加α-溴代異丁酰溴(BIBB),滴加時間為1 h,滴加完,升溫至室溫,反應時間為24 h。(2)制備四臂聚合物PtBA、P(tBA-TPEG)時:反應溫度為85℃,反應時間為18 h。(3)水解反應:三氟乙酸與水的體積比為9:1,反應時間為10 h。對合成的FAPC進行紅外光譜、表面張力、表觀吸附量及Zeta電位等表征;并探討季戊四醇、α-溴代異丁酰溴、丙烯酸叔丁酯、異戊烯醇聚氧乙烯醚的用量,異戊烯醇聚氧乙烯醚的分子量、種類等各實驗因素對FAPC性能的影響。為更好評價FAPC的性能,將FAPC與商用梳形聚羧酸減水劑ZD進行性能上的比較研究,結(jié)果表明:FAPC的凈漿分散性及分散保持性、砂漿分散性及分散保持性、減水率、抗泥性、對水泥的適用性及砂漿力學性能等性能均優(yōu)于ZD。
[Abstract]:At present, with the rapid development of construction technology, the performance requirements of concrete used are improved, the corresponding performance requirements of water reducer will be higher, and the traditional comb-shaped polycarboxylic acid water reducer can not be applied gradually. Meet the requirements of high performance concrete. The traditional comb-shaped polycarboxylic acid superplasticizer is a random copolymer, and its molecular structure is not clear, so it can not reveal the relationship between structure and properties in essence. Therefore, in order to make up for the shortage of comb-shaped polycarboxylic acid superplasticizer, the four-arm AB type diblock polycarboxylic acid superplasticizer FAPC was synthesized by atom transfer radical polymerization. In this study, pentaerythritolol (PET) was used as the core, tert-Butyl acrylate (tert-Butyl acrylate) and isopentenol polyoxyethylene ether (TPEG) as monomers, and pentamyldiethylenetriamine (Pentamyldiethylenetriamine) (Cubr) as catalyst. Four-arm AB type diblock polycarboxylic acid superplasticizer FAPCs was synthesized by atom transfer radical polymerization (ATRP). The optimum experimental conditions are as follows: (1) the ratio of each substance is: n (PET): n (BIBB): n (t BA): n (TPEG) 1: 2: 1 43: 25 n (initiator): n (Cubr): n (PMDETA) 1: 4: 8; other experimental conditions: (1) preparation of small molecule initiator: in ice bath (0 鈩，

本文編號：2061702