Swift cooling crystallization of vanillin was investigated in water, ethanol, isopropanol and ethyl acetate. Morphology and polymorph evolution of vanillin were discussed in terms of solvent, supersaturation ratio and silica template. PXRD, DSC, FTIR and microscope were used to identify polymorphs of vanillin. Results showed that the nucleated polymorphs of vanillin depended largely on the solvent, supersaturation ratio and silica template. Low supersaturation ratios favor the nucleation of stable form I in water, and high supersaturation ratio exceeds 7 generating 100% metastable form II. However, if the supersaturation ratio is too high (S>8), liquid–liquid phase separation will occur, and no crystals could be obtained. In other solvents such as ethanol, isopropanol and ethyl acetate, only form I was obtained. However, it should be noted that the morphology of form I prepared in ethanol, isopropanol and ethyl acetate is distinct from that obtained in water, the former is flake-like and the latter is rod-like. The nucleation of vanillin from different solution was also studied with the presence of SiO₂, SiO₂–NH₂ and SiO₂−COOH templates, which did not change the nucleated polymorph of vanillin, but changed the nucleation and growth rate of stable form I.

研究了香兰素在水、乙醇、异丙醇和乙酸乙酯中的快速冷却结晶。从溶剂、过饱和比和硅胶模板方面讨论了香兰素的形态和多晶型演变。PXRD、DSC、FTIR和显微镜被用来鉴定香兰素的多晶型物。结果表明，香兰素的成核多晶型在很大程度上取决于溶剂、过饱和比和硅胶模板。低过饱和比有利于稳定形式 I 在水中的成核，高过饱和比超过 7 产生 100% 亚稳形式 II。但是，如果过饱和比太高（S>8)，会发生液-液相分离，无法获得晶体。在其他溶剂如乙醇、异丙醇和乙酸乙酯中，仅获得晶型 I。但需要注意的是，I型在乙醇、异丙醇和乙酸乙酯中制备的形态与在水中制备的形态不同，前者呈片状，后者呈棒状。在SiO ₂、SiO ₂ -NH ₂和SiO ₂ -COOH模板的存在下，研究了不同溶液中香兰素的成核，这些模板没有改变香兰素的成核多晶型，但改变了稳定形式I的成核和生长速率.