A　viscosity-reducing　polycarboxylate　superplasticizer　VR-PCE-TR　with　a　narrow　molecular　distribution　was　synthesized　from　thermally　initiated　reversible　addition-fragmentation　chain　transfer　(RAFT)　polymerization　of　polyoxyethylene　polyoxypropylene　isopentenol　ether　(IPEPPG),　2-methyl-2-butylsulfanyl-thiocarbonylsulfanyl-propionic　acid　and　maleic　anhydride　in　a　continuous　tubular　reactor,　and　characterized　by　1HNMR,　FTIR　and　GPC.　VR-PCE-TR　was　then　evaluated　for　its　influence　on　the　working　performance　and　rheological　properties　of　concrete,　and　for　performance　comparison　with　viscosity-reducing　polycarboxylic　acid　superplasticizers　prepared　by　conventional　aqueous　free　radical　polymerization　in　tank　reactor.　The　results　showed　that,　when　the　mass　fraction　of　polycarboxylate　superplasticizer　solution　was　10%,　VR-PCE-TR　exhibited　the　lowest　surface　tension　(30.65　mN/m).　When　the　superplasticizer　mass　fraction　was　0.8%,　VR-PCE-TR　displayed　a　higher　adsorption　capacity　for　cement　particles　(2.803　mg/g).　When　the　dosage　(based　on　the　mass　of　cement,　the　same　below)　of　superplasticizer　was　0.13%,　the　cement　slurry　with　VR-PCE-TR　showed　better　dispersion　and　dispersion　retention　performance,　while　when　the　dosage　of　superplasticizer　was　0.4%,　the　cement　slurry　with　VR-PCE-TR　showed　a　lower　yield　stress　(1.3　Pa)　and　lower　plastic　viscosity　(0.26　Pa·s).　The　continuous　tubular　reactor　avoided　the　material　deoxygenation　step　and　could　maintain　the　polymerization　control　and　polymerization　reaction　rate,　therefore,　the　prepared　VR-PCE-TR　had　a　narrower　relative　molecular　mass　distribution　(polydispersity　index　was　1.19),　and　thus　had　better　viscosity　reduction　effect　and　application　performance.　©　2024　Fine　Chemicals.　All　rights　reserved.