[C14MIM]Br离子液体对聚丙烯超临界CO2发泡性能的影响

本文对PP/C₁₄MIM]Br体系的熔融过程和对CO₂的吸收, 以及C₁₄MIM]Br在PP基体中的分散状态进行了研究, 并初步考察了C₁₄MIM]Br对PP发泡性能的影响.

Effect of [C14MIM]Br Ionic Liquid on Foaming Behavior of Polypropylene by Supercritical CO2

Effects of an ionic liquid, 1-n-tetradecyl-3-methylimidazolium bromide(C14MIM]Br), as a foaming additive on the foaming behavior of polypropylene(PP) by supercritical CO2 technique was reported. Mass ratio of PP/C14MIM]Br up to 100∶10 was incorporated via melt blending. The melting behavior and fractured morphology of PP/C14MIM]Br samples were investigated by differential scanning calorimetry(DSC) and scanning electron microscopy(SEM), respectively. The CO2 sorption was measured by commonly accep-ted gravimetric method. The results of DSC and CO2 sorption experiments show that C14MIM]Br has little effect on the crystallinity, melting point and the mass uptake of CO2 of PP. SEM images reveal that C14MIM]Br forms a well-dispersed phase, whose size increases with C14MIM]Br content, in the PP matrix. The foamed PP/C14MIM]Br samples exhibit close cell structure, increased cell size and decreased un-foamed region and bulk density, compared with pure PP foamed under the same saturation conditions of 155 ℃/10 MPa, indicating ionic liquid C14MIM]Br has significant effect on the foaming behavior of PP.