两亲性树形-线团大单体的合成及其丙烯酸共聚乳液的流变行为

将3,4,5-三(十六烷基氧基)苯甲酰氯先后与分子量为1000的聚乙二醇、甲基丙烯酰氯反应合成了一种新的可聚合两亲性树形-线团大单体——3,4,5-三(十六烷氧基)苯甲酰氧基聚氧乙烯甲基丙烯酸酯(6).通过核磁、红外、元素分析等对产物进行了表征.然后将其与甲基丙烯酸、丙烯酸乙酯进行乳液共聚合,制备了一种疏水树形侧链改性...

SYNTHESIS OF AMPHIPHILIC DENDRON-COIL MACROMONOMER AND RHEOLOGICAL PROPERTIES OF ITS ACRYLATE COPOLYMER EMULSION

A novel amphiphilic dendron-coil macromonomer —— 3,4,5-tri(n-hexadecyloxy)benzoyloxy polyoxyethylene methacrylate was synthesized by esterification of polyoxythylene(molecular weight M=1000) with 3,4,5-tri(n-hexadecyloxy)benzoyl chloride and followed by methacrylic chloride.The compound was then characterized by means of NMR and FTIR,elementary analysis.Moreover,a new kind of hydrophobically modified alkali-soluble emulsion copolymer(DHASE) was synthesized by emulsion copolymerization of amphiphilic macromonomer 6 with mathacrylic acid and ethyl acrylate.As a comparison,an alkali-soluble emulsion copolymer(MAAEA) of mathacrylic acid and ethyl acrylate was synthesized also.The rheological properties of DHASE and MAAEA aqueous solutions under different solid contents and pH values were studied using controlled stress rheometer.It was found that DHASE aqueous solutions had outstanding alkali-thickening and thixotropy properties and larger zero shear rate viscosity than MAAEA aqueous solutions when pH ≥ 6.8 and the solid content of copolymer ≥1.0 wt%.At the same time,the storage modulus G′ was always larger than the loss modulus G″ over the entire range of frequencies for DHASE aqueous solutions,suggesting formation of physical network structure due to hydrophobic associations of dendron alkyl trails in DHASE aqueous solutions.On the contrary,the MAAEA aqueous solution exhibited Newtorian fluid behavior and its G″ was always smaller than G′ under the same condition.The results demonstrated the potential of this novel amphiphilic dendron-coil macromonomer in hydrophobically modified alkali-soluble emulsion copolymers and associative thickeners in the future.