【摘要】 采用辛胺改性海藻酸钠,并以其通过物理混合和化学接枝2种途径活化SiO2纳米粒,利用红外光谱、核磁共振氢谱和动态光散射等对产物进行了表征,并超声乳化制备了其相应的Pickering乳液,进而对乳液的形貌进行了观察。结果表明:海藻酸钠上成功接枝了辛胺侧链;经2种途径活化后的SiO2纳米粒粒径均大于未活化的SiO2纳米粒,分别增至467.0和414.4 nm;其Zeta电位较SiO2纳米粒自身的-17.0 mV也发生了变化,分别为-43.9和-35.2 mV。同时,活化后的纳米粒具有了较好的乳化性能,尤其是通过表面化学接枝改性海藻酸钠的SiO2纳米粒,其形成的Pickering乳液液滴分散性好,大小均一,平均粒径为5μm。更多还原

【Abstract】 SiO2nanoparticles were activated by octylamine modified sodium alginate via two ways,physical mixing and chemical grafting. The activated SiO2nanoparticles were characterized by FTIR,1HNMR and DLS, et al. Then Pickering emulsions were prepared with the activated SiO2nanoparticles under assistance of ultrasonic wave,and morphology of the emulsions was observed. Experimental results showed that octylamine side chain was successfully grafted onto the sodium alginate. The particle size of activated SiO2nanoparticles via both physical mixing and chemical grafting ways is larger than that of unactivated SiO2nanoparticles,and increases to 467. 0 and 414. 4 nm respectively. Surface potential of activated SiO2nanoparticles changes to- 43. 9 and- 35. 2 mV respectively,which is lower than that of unactivated SiO2nanoparticles,which shows a surface potential of- 17. 0 mV. Meanwhile,the activated SiO2nanoparticles reveal better emulsifying properties,especially the nanoparticles activated by chemical grafting way could produce a more stable Pickering emulsion with better droplet dispersion,uniform size and with average particle diameter of 5 μm.更多还原