The latex of acrylate copolymer with gradient structure of molecules was synthesized by gradient emulsion polymerization with using sodium dodecyl biphenylate disulfatepoly(DSB) as emulsifier, sodium 1-allyloxy-2-hydroxypropyl sulfonate(COPS-1), sodium acrylamide-2-methylpropane sulfonate (AMPS-Na) or HS-10 as surface active monomer separately, BA, MMA and MAA as co-monomers. The effect of the amount of COPS-1 on the size and distribution of particles, as well as mechanical stability, thermal property, microphase separation, water absorptivity and tensile strength of the film formed by the latex were investigated. The experimental results show that, when the COPS-1 content is fixed at 70％ (mass), the monomers have high conversion(x=97.5％) and the film has good mechanical stability, low water absorptivity (w=4.25％) and high tensile strength (μ=0.85 MPa). The DSC analysis shows that the coplymer only has a single wide glass transition peak, this indicates that the copolymer has gradient structure. SEM shows that the microphase separation in the copolymer is few.%采用梯度乳液聚合法,以十二烷基联苯醚二磺酸钠(DSB)为乳化剂,分别引入表面活性单体1-烯丙氧基-2-羟丙基磺酸钠(COPS-1),2-丙烯酰胺基-3-甲基丙磺酸钠(AMPS-Na)以及烯丙基烷基酚聚氧乙烯醚硫酸盐(HS-10),通过丙烯酸丁酯(BA)/甲基丙烯酸甲酯(MMAA)甲基丙烯酸(MAA)三元共聚反应,制备了具有分子间梯度结构的丙烯酸酯乳液.讨论了表面活性单体对乳液转化率、平均粒径及分布和机械稳定性、涂膜的热性能、微相分离、吸水率和拉伸强度的影响.实验结果表明当COPS-1质量分数为70%时,单体的转化率高(x=97.5%)、乳液的机械稳定性好,涂膜吸水率低(w=4.25%),且拉伸强度高(μ=0.85 MPa).DSC和SEM分析表明丙烯酸酯梯度共聚物的玻璃化转变区为单一的宽峰,微相分离也得到明显改善.
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