CAJ | 학술논문

低分子聚醚减缩剂是目前市场上应用最为广泛的一类减缩剂,但其减缩机理尚不明确。选用两亲性二乙二醇单丁醚作为减缩剂,与其分子结构不同但同为两亲性的二丙二醇作为对比样,探索两亲性低分子聚醚减缩机理。通过收缩性能实验表明,二乙二醇单丁醚减少干燥收缩与自收缩的能力明显优于二丙二醇,掺量为2%时,二乙二醇单丁醚与二丙二醇分别减少干燥收缩44.4%与19.2%,减少自收缩73.1%与23.8%。通过等离子光谱（ICP）、有机碳分析仪（TOC）探索了二丙二醇及二乙二醇单丁醚对水泥浆体孔溶液性能的影响,结果表明,减缩能力与减缩剂的分子结构密切相关。水泥水化基本完全后,两亲性二丙二醇与二乙二醇单丁醚不同程度地进入到水泥浆体孔溶液中,28d龄期时使孔溶液中K＋含量分别降低13.8%和35.4%,Na＋含量分别降低15.6%和39.6%,而孔溶液的表面张力也分别降低9.2%与46.2%。由此可见,两亲性减缩剂的减缩能力与其孔溶液中K＋、Na＋浓度成反比且会不同程度地降低孔溶液的表面张力,从而表现出不同的减缩能力。
저분자취미감축제시목전시장상응용최위엄범적일류감축제,단기감축궤리상불명학。선용량친성이을이순단정미작위감축제,여기분자결구불동단동위량친성적이병이순작위대비양,탐색량친성저분자취미감축궤리。통과수축성능실험표명,이을이순단정미감소간조수축여자수축적능력명현우우이병이순,참량위2%시,이을이순단정미여이병이순분별감소간조수축44.4%여19.2%,감소자수축73.1%여23.8%。통과등리자광보（ICP）、유궤탄분석의（TOC）탐색료이병이순급이을이순단정미대수니장체공용액성능적영향,결과표명,감축능력여감축제적분자결구밀절상관。수니수화기본완전후,량친성이병이순여이을이순단정미불동정도지진입도수니장체공용액중,28d령기시사공용액중K＋함량분별강저13.8%화35.4%,Na＋함량분별강저15.6%화39.6%,이공용액적표면장력야분별강저9.2%여46.2%。유차가견,량친성감축제적감축능력여기공용액중K＋、Na＋농도성반비차회불동정도지강저공용액적표면장력,종이표현출불동적감축능력。
The low molecular polyether shrinkage reducing agent is most widely used on the market at present,but the shrinkage mechanism is still unclear.In order to explore the shrinkage mechanism of water-soluble polyether,the diethylene glycol monobutylether was selected as shrinkage reducing agent（SRA）,and the dipropylene glycol which has a different structure was used as a contrast sample.The shrinkage performance experiments showed that the diethylene glycol monobutylether reduced the drying shrinkage and the autogenous shrinkage at 28d by about 44.4% and 73.1% while the dipropylene glycol reduced the drying shrinkage and autogenous shrinkage by about 19.2% and 23.8%.The properties of the cement paste’s pore solution were measured by ICP and TOC,and the results showed that the shrinkage reducing ability is closely related to the molecular structure of SRA.The pore solutions are filled with dipropylene glycol and diethylene glycol monobutylether in different concentrations after hydration.The K＋ concentrations of the pore solution were reduced by about 13.8% and 35.4% at 28d by dipropylene glycol and diethylene glycol monobutylether respectively while the Na＋ concentrations were reduced by about 15.6% and 39.6%,and the surface tensions were also reduced by about 9.2% and 46.2%.It can be seen that,for the amphiphilic SRAs,the shrinkage reducing ability is inversely proportional to the K＋,Na＋ concentrations and why they perform different shrinkage reductions is that the pore solutions were filled with them in different amounts which can reduce the surface tension and the K＋,Na＋ concentrations in different degrees.