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1、http://www.taql.com.cn/http://www.dyqzjx.com/http://www.taianshiyantai.com/http://www.tshbcl.com/解读聚羧酸盐高性能减水剂的作用机理Interpretationofpolycarboxylicacidsalt,themechanismofthehighperformancewaterreducingagent聚羧酸盐高性能减水剂是由带有磺酸基、羧基、氨基以及含有聚氧乙烯侧链等的大分子化合物,在水溶液中
2、,经过自在基共聚原理合成的具有梳型构造的高分子外表活性剂。Polycarboxylicacidsaltofhighperformancewaterreducingagentismadewithasulfonicgroup,carboxyl,amino,andcontainingpolyoxyethylenesidechainofmacromolecularcompounds,suchasinaqueoussolution,afteracomfortablebasecopolymerization
3、principleofsyntheticpolymersurfaceactiveagentwiththecombtypestructure.合成聚羧酸盐高性能减水剂所需的主要原料有:甲基丙烯酸、丙烯酸、丙烯酸乙酯、丙烯酸羟乙酯、烯丙基磺酸钠、甲基丙烯酸甲酯、2-丙烯酰胺基-2-甲基丙烯酸、甲氧基聚氧乙烯甲基丙烯酸酯、乙氧基聚乙二醇丙烯酸酯、烯丙基醚等,在聚合过程中可采用的引发剂为:过硫酸盐水性引发剂、过氧化苯甲酰、偶氮二异丁氰;链转移剂有:3-疏基丙酸、疏基乙酸、疏基乙醇以及异丙醇等。http:
4、//www.taql.com.cn/http://www.dyqzjx.com/http://www.taianshiyantai.com/http://www.tshbcl.com/Synthesisofpoly(carboxylicacidsaltofmainrawmaterialforhighperformancewaterreducingagentare:methylacrylate,ethylacrylate,acrylicacid,hydroxyethylacrylate,sodiu
5、mallylsulfonicacid,methylmethacrylate,2-acrylamide-2-methylacrylate,methoxypolyoxyethylenemethylacrylateandethoxypolyethyleneglycolacrylate,allylether,etc.,canbeusedintheprocessofpolymerizationinitiatorfor:water-basedpersulfateinitiator,benzoylperoxi
6、de,azodiisobutylcyanogen;Chaintransferagenthas:3-hydrophobicthinbaseofpropionicacid,aceticacid,ethanolandisopropylalcohol.聚羧酸盐高性能减水剂是一种新型减水剂,具有许多突出的优点,但其作用机理目前尚未完整分明,以下是其中的一些观念:Polycarboxylicacidsaltofhighperformancewaterreducingagentisanewtypeofwate
7、rreducingagent,hasmanyprominentadvantages,butitsmechanismhasnotyetcompleteandclear,herearesomeideas:http://www.taql.com.cn/http://www.dyqzjx.com/http://www.taianshiyantai.com/http://www.tshbcl.com/聚羧酸类聚合物对水泥有较为显著的缓凝作用,主要由于羧基充任了缓凝成分,R-COO~与Ca2+离子作用构成络
8、合物,降低溶液中的Ca2+离子浓度,延缓Ca(OH)2构成结晶,减少C-H-S凝胶的构成,延缓了水泥水化。Polycarboxylicacidpolymersofcementhaverelativelysignificantretardingeffect,mainlybecauseofthecarboxylfilledretardedcomponents,R-COO~andCa2+ionsconstitutesacomplex,reducetheCa2+ionconcentrationinthe