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考察了表面活性剂存在条件下利用脲醛树脂杂化沉淀制备氧化硅微球的反应过程.不同表面活性剂条件下所得的氧化硅微球产物各不相同.焙烧后P123(PEO20-PPO70-PEO20)条件的杂化微球分解成壳状氧化硅碎片,CTAB(十六烷基三甲基溴化铵)条件的氧化硅严重变形,体积收缩到前体粒子的九分之一,而SDBS(十二烷基苯磺酸钠)条件的产物球形貌良好的保留了下来.BET分析揭示P123和CTAB条件下的氧化硅比表面分别增加了20%和13%,而SDBS(十二烷基苯磺酸钠)条件的产物在表面积不变的条件下孔体积和孔径减少了一半.定量分析证明SDBS条件下氧化硅纳米粒子的杂化受到了明显抑制,而正硅酸乙酯浸渍方式的补硅量接近一倍,这种优化的几何结构保证了氧化硅微球产物的完整性和稳定性.
The reaction process of preparing silica microspheres by urea-formaldehyde resin hybrid precipitation was investigated in the presence of surfactants.The products of silica microspheres obtained under different surfactants were different.P123 (PEO20-PPO70-PEO20) Under the conditions of hybrid microspheres decomposed into shell-like silica fragments, the silicon oxide under CTAB (cetyltrimethylammonium bromide) conditions deforms severely, shrinking in volume to one-ninth of the precursor particles while SDBS Sodium dodecylbenzenesulfonate) .BET analysis revealed a 20% and 13% increase in the specific surface areas of silica at both P123 and CTAB conditions, whereas SDBS (dodecylbenzene Sodium sulfonate), the pore volume and pore diameter were reduced by half under the condition of the same surface area.Quantitative analysis showed that the hybridization of silica nanoparticles under SDBS was significantly inhibited, while the addition of tetraethoxysilane The amount of silicon is nearly doubled. This optimized geometry ensures the integrity and stability of the silica microsphere product.