摘要
以单滴法评价了单一聚氧乙烯-聚氧丙烯-聚氧乙烯三嵌段共聚物(Pluronic L61、L64、F68、F108)和卵磷脂(PC)以及二者混合作为乳化剂对油/水界面膜的稳定效果。结果表明,当乳化剂分子在界面上排列紧密时,具有较长PEO嵌段的Pluronics有利于形成稳定的油/水界面膜。但以单一Pluronic嵌段共聚物作为乳化剂时,由于PPO嵌段长度限制了其弯曲插入油相的自由度,导致较长PEO嵌段间相互推挤,降低了分子在界面上排列的紧密程度。加入PC可促进混合吸附膜中分子的紧密排列,进而发挥长PEO嵌段包裹油滴外壳的稳定优势。实验表明,F68+PC和F108+PC 2种混合乳化剂形成了稳定的混合膜,二者组成以Pluronics(0.0125 g/mL)与PC(0.0167 g/mL)较佳。
The stabilities of the adsorption films of the o/w emulsions were investigated with a home made drop stability apparatus in which isopropyl myristate（IPM） was used as the oil and Pluronic copolymers（ L61, L64, F68 and F108）, lecithin（PC） and their mixture were used as the emulsifier, respectively. The results show that Pluronic molecule with a long PEO block benefited the stabilization of the film. When single Pluronic copolymer was used as the emulsifier, however, the limited length of the PPO blocks restricted their bending to insert the oil drop, resulting in the reduction of the compactness of the molecules arranging at the oil/water interface because of the repulsion between the long PEO blocks. The addition of PC improved the arrangement of the emulsifier molecules at the oil/water interface and promoted them to pack tightly. Thus the long PEO blocks wrapped on the surface of oil drop stabilized the oil-drops in water. The 13resent work has demonstrated that the mixed emulsifiers of F68 ＋ PC or F108 ＋ PC with 0. 012 5 g/mL Pluronics and 0. 016 7 g/mL PC can form a stable adsorption film at the oil/water interface.
出处
《应用化学》
CAS
CSCD
北大核心
2007年第7期747-751,共5页
Chinese Journal of Applied Chemistry
基金
国家自然科学基金(20373012)
福建省教育厅科技项目(jb05022)资助项目
