纳米SiO2/聚氨酯-含氟丙烯酸酯杂化乳液的合成与表征

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。

Synthesis and characterization of nano-SiO2/polyurethane-fluorinated polyacrylate hybrid emulsion

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.