Abstract: A core-shell type nano-SiO₂/polyurethane-fluorinated acrylate（SiO₂/FPUA)hybrid emulsion was synthesized by seeded emulsion polymerization using polyurethane（PU)as seed, which served as shell phase in the hybrid emulsion mentioned above, with the core phase consisting of nano-SiO₂ modified by γ-(methacryloxy)propyltrimethoxy silane（KH-570), methyl methacrylate（MMA), butyl acrylate（BA)and dodecafluoroheptyl methacrylate（DFMA).The influence of the amount of nano-SiO2 and fluorine-containing monomer（DFMA)on emulsion polymerization process and surface hydrophobic properties of the latex films were discussed.The nano-SiO₂/fluorinated polyacrylate emulsion and the latex film were characterized by Fourier transform infrared spectrum（FT-IR), transmission electron microscopy（TEM), contact angle（CA), thermogravimetry （TG)， differential scanning calorimetry（DSC)and mechanical properties test（MPT）analysis.The results indicated that the latex particles showed a “reverse core-shell” structure, with PA as core and PU as shell, and the hydrophobicity and comprehensive properties of the latex film were greatly improved owing to the synergistic effect of DFMA and nano-SiO₂.

Key words: seeded emulsion polymerization, modified nano-SiO₂, fluorinated acrylate, hydrophobicity, inverse core-shell structure

摘要： 采用种子乳液聚合法，以聚氨酯（PU）乳液为种子（在聚合过程中为壳相），甲基丙烯酸甲酯（MMA）、丙烯酸丁酯（BA）、甲基丙烯酸十二氟庚酯（DFMA）和γ-甲基丙烯酰氧丙基三甲氧基硅烷（KH-570）改性的纳米SiO₂组成的混合物为核相，合成了具有核壳结构的纳米SiO₂/聚氨酯-含氟丙烯酸酯（SiO₂/FPUA）复合乳液。考察了纳米SiO₂和DFMA用量对乳液聚合过程及乳胶膜性能的影响。通过傅里叶红外光谱（FT-IR）、接触角（CA）、透射电子显微镜（TEM）、热重（TG）、差示扫描量热仪（DSC）和力学性能测试（MPT）等表征乳液的结构形态、乳胶膜的表面性能和综合性能。结果表明：乳胶粒子呈现“反相核壳”结构，以聚丙烯酸酯（PA）相为核，PU相为壳；由于纳米SiO₂和DFMA的协同作用，涂膜的疏水性和综合性能得到了较大的提高。

关键词: 种子乳液聚合, 改性纳米SiO₂, 含氟丙烯酸酯, 疏水性, 反相核壳结构