溶剂抽提对硫化胶试样扫描电子显微镜成像的影响

Effect of Solvent Extraction on SEM Imaging of Vulcanizate Sample

以白炭黑填充的丁苯橡胶/顺丁橡胶并用胶(硫化胶)为例,采用有机溶剂甲苯和丙酮对硫化胶进行抽提,再冷冻切片,对切片试样进行扫描电子显微镜(SEM)分析,以评价硫化胶中填料的分散状况。结果表明:在SEM分析中,未对硫化胶进行溶剂抽提,析出的填充油和其他助剂遮盖试样表面的部分区域,影响对硫化胶中填料分散状况的判断;使用弱极性甲苯或强极性丙酮在不同温度下对硫化胶进行抽提,可以消除硫化胶中其他助剂析出的影响,试样的成像效果明显改善,可以很好地观察试样表面的填料分散状态;溶剂抽提温度对试样的SEM成像效果无明显影响。

In this study,the effect of solvent extraction on scanning electron microscope(SEM)imaging of vulcanizate samples was studied by taking SBR/BR blend(vulcanizate)filled with silica as an example.The vulcanizate was extracted with toluene and acetone,then frozen and sectioned,and the sectioned samples were analyzed by SEM to evaluate the dispersion of the filler in the vulcanizate.The results showed that,in SEM analysis,without solvent extraction of vulcanizate,some areas on the surface of the sample were covered by precipitating filling oil and other additives,which affected the judgment of filler dispersion of the vulcanizate.When solvent such as toluene with weak polarity or acetone with strong polarity was used to extract the vulcanizate at different temperatures,the influence of other additives precipitated from the vulcanizate could be eliminated,and the imaging effect of the sample was improved significantly,so the dispersion of the fillers on the sample surface could be well observed.In addition,the solvent extraction temperature had no significant effect on SEM imaging of the sample.