支化型交替聚(苯乙烯-alt-马来酸酐)自组装胶束的制备及其乳化性能

Emulsifying Performance of Self-Assembled Micelles Based on Branched Alternating Copolymer Poly(styrene-alt-maleic anhydride)

利用支化型交替聚（苯乙烯-alt-马来酸酐） （BPSMA）在选择性溶剂DMF-H2O中自组装制备球形胶束，以该胶束作为新型颗粒乳化剂稳定油-水体系，探讨胶束浓度和pH对BPSMA胶束乳化性能的影响。用紫外分光光度计（UV-Vis）追踪了聚合物溶液自组装过程；粒径及Zeta电位分析仪和透射电子显微镜（TEM）表征了BPSMA胶束的基本性质；利用光学显微镜分析了乳液性质，扫描电子显微镜（SEM）观察了胶束在固化后的油滴表面的形貌。结果表明：BPSMA胶束具有优异的乳化效率，在极低的质量浓度下（0.25 -1.00 mg/mL）亦可长期稳定乳液；BPSMA胶束所稳定的乳液具有明显的pH响应性，当pH≤6时，胶束呈球形颗粒状吸附并稳定于油水界面，当pH〉6时，胶束从油水界面脱离，乳液破乳；此外，BPSMA胶束作为颗粒乳化剂还具备良好的普适性，可以长效稳定碳酸二辛脂、辛酸丙基庚酯、硅油、棕榈酸异辛酯和润肤油脂等。

Spherical micelles self-assembled from branched alternating copolymer poly（styrene-alt-maleic anhydride） （BPSMA） in selective solvent DMF-H2O was utilized as novel particulate emulsifiers to stabilize white oil-water interface. The influence of both micelle concentration and pH in micelle solution on the emulsifying performance of micelles was investigated. The self-assembly of BPSMA in solution was traced by UV-Vis and the properties of the formed BPSMA micelles were characterized by particle size and Zeta potential analyzer and Transmission Electron Microscopy （TEM）. The morphology of emulsion droplets was characterized by optical microscope, the morphologies of micelles at oil-water interface was obserbed by Scanning Electron Microscope （SEM）. BPSMA micelles exhibit excellent emulsifying efficiency, and the emulsions stabilized by BPSMA micelles shows distinguish long-term stability, even with very low micelle mass concentration of 0.25—1.00 mg/mL. The emulsions are pH-dependent. Stable emulsions could be obtained with micelles adsorbing at the interface as pH≤6, while most oil separated out as pH〉6. Additionally, BPSMA micelles also can stabilize dicaprylyl carbonate, propylheptyl caprylate, silicone oil, isooctyl palmitate and sensoft oil, etc.