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报道了油相在高度分散状态下的结晶特性 .应用超声波检测技术分别研究了降温和升温过程中体积分数为 2 0 %的O/W型乳状液中油相 (正十六烷 )粒子 (平均直径d32 =0 .3 6± 0 .0 2 μm)内部晶体的形成和熔化、在结晶点的晶体生长情况以及在高于结晶温度的情况下结晶粒子对未结晶粒子的诱导结晶等 .结果表明 ,与体相结晶相比 ,分散相的结晶需要更深的过冷程度 (数值取决于乳化剂类型和粒子大小 ) ;在结晶温度下 ,粒子内晶体的成核和生长过程与粒子间的相互作用关系不大 ;油相成分相同时 ,结晶了的粒子会诱使未结晶的粒子发生固化 .在乳状液体系中 ,完全液态的粒子的成核被认为是一种均相成核 ,而液固态粒子共存的体系的结晶有可能遵循一种异相成核机理 .
The crystallization characteristics of the oil phase in a highly dispersed state were reported.The oil phase (n-hexadecane) particles (average particle diameter) in O / W emulsions with a volume fraction of 20% d32 = 0.36 ± 0.020 μm), the crystal growth and crystallization at the crystal point, and the induced crystallization of the un-crystallized particles by the crystal particles at a temperature higher than the crystallization temperature, etc. As a result, The crystallization of the dispersed phase requires a deeper degree of supercooling compared to bulk crystallization (the magnitude depends on the type of emulsifier and the size of the particles); at the crystallization temperature, the intergranular interaction between the nucleation and growth of the crystals within the particle Not large; the same oil phase ingredients, the particles will induce the crystallization of non-crystalline particles to solidify in the emulsion system, completely liquid particles nucleation is considered a homogeneous nucleation, and liquid-solid particles The coexistence of the crystallization system may follow a heterogeneous nucleation mechanism.