共溶剂对超临界CO2注入技术制备聚丙烯/SiO2纳米复合材料的影响

采用超临界CO2注入技术制备聚合物-无机纳米粒子复合材料, 以乙醇作为共溶剂, 在超临界CO2中将正硅酸乙酯(TEOS)注入到聚丙烯(PP)中, 重点研究共溶剂乙醇对TEOS在PP中注入率的影响. 实验结果表明注入率随着共溶剂加入先增加后减小. 同时研究了在共溶剂的存在下其他实验条件对注入率的影响. 并采用卢瑟福背散射能谱法(RBS)分析了聚丙烯/SiO2纳米复合材料的注入元素深度分布, 发现Si元素在PP中的浓度分布不均匀, 随着深度的增加而减小.

Synthesis of Polypropylene/Silica Hybrid Materials by Supercritical CO2 Impregnation Using a Co-Solvent

Polymer/inorganic hybrid materials were prepared by supercritical carbon dioxide (scCO2) impregnation. Tetraethyl orthosilicate (TEOS) was infused into polypropylene (PP) strips in scCO2 using ethanol as the co-solvent. The effect of this co-solvent on mass uptake was investigated. We found that the mass uptake of TEOS into PP strips increased to a maximum and then decreased after the addition of more co-solvent. The effects of other impregnation conditions on the mass uptake were also investigated with using ethanol. Moreover, the depth profile of the infused elements inside the polymer/inorganic hybrid material was obtained by Rutherford backscattering spectrometry (RBS). The RBS spectrum demonstrated that the concentration of Si in the PP strips was not uniform and decreased with infusion depth.