微波辐射梳形聚羧酸共聚物合成及其分散性能

以自制顺丁烯二酸聚乙二醇(n=9)单酯(MAPEG)、烯丙基磺酸钠(SAS)和顺丁烯二酸酐(MA)为单体,过硫酸铵为引发剂,在微波辐射下合成了梳形聚羧酸共聚物,并用傅里叶变换红外光谱对其结构进行了表征。考察了辐射功率和时间对梳形聚羧酸共聚物分子结构及分散性能的影响。实验结果表明,在微波辐射下,共聚反应所需时间很短,且梳形聚羧酸共聚物的分散性稳定。在n(SAS)∶n(MA)∶n(MAPEG)=3.6∶4.3∶1、引发剂用量1.0%(占总单体的质量)、辐射功率650W、辐射时间5min条件下,所得梳形聚羧酸共聚物的特性黏数为2.63×10-2dL/g;在水与水泥的质量比为0.35、梳形聚羧酸共聚物(n(SAS)∶n(MA)∶n(MAPEG)=3.6∶4.3∶1、引发剂用量1.0%、辐射功率260W和辐射时间5～10min或辐射功率130～650W和辐射时间6～10min)掺杂量(质量分数)为0.4%时,水泥净浆流动度稳定在230mm左右。

Synthesis of Comb-Shaped Polycarboxylic Acid Copolymer Under Microwave Irradiation and Its Dispersibility

Comb-shaped polycarboxylic acid copolymer was synthesized by copolymerization of self-made maleic acid polyethylene glycol(n=9)momo ester(MAPEG),sodium allylsulfonate(SAS)and maleic anhydride(MA)initiated by ammonium persulfate(APS)under microwave irradiation.Structure of copolymer was characterized by means of FTIR.Effects of microwave irradiating power and irradiating time on structure and dispersibility of copolymer were studied.The copolymerization time is short and dispersibility of copolymer is stable.Under conditions of n(SAS) ∶n(MA) ∶n(MAPEG)3.6 ∶4.3 ∶1,mass fraction of APS in total monomers 1.0%,micro irradiating power 650 W and irradiating time 5 min,intrinsic viscosity of the copolymer is 2.63×10-2 dL/g.When 0.4%(mass fraction)of the copolymer(irradiating power 260 W for 5-10 min or 130-650 W for 6-10 min)is doped and mass ratio of water to cement is 0.35,fluidity of cement slurry can reach 230 mm and is stable.