乳液聚合接枝聚苯乙烯/多壁碳纳米管复合材料的制备及性能研究

Preparation and Properties of Multi-walled Carbon Nanotubes Composites with Polystyrene Prepared by Emulsion Polymerization

采用乳液聚合的方法制备了多壁碳纳米管接枝聚苯乙烯（MWNTs—g-PS）聚合物，然后与聚苯乙烯（PS）熔融共混制得MWNTs-g-PS／PS复合材料。红外光谱分析（FTIR）证实了PS在MWNTs上的接枝反应的发生，透射电镜（TEM）照片显示PS可以有效地接枝到MWNTs上，并且分布比较均匀。通过对样品的热性能进行研究，得出纯的多壁碳纳米管具有良好的热稳定性，基本无失重。MWNTs—g-PS在100—500℃范围内的失重是由于MWNTs—g-PS表面的Ps的热分解而形成的。通过扫描电子显微镜（SEM）对MWNTs在PS基体中的分散状态进行研究。MWNTs—g-PS在Ps基体中的分散情况比纯MWNTs在Ps集体中分散情况好得多。这是由于PS链段在MWNTs表面的接枝包覆，一方面克服了碳纳米管分子间范德华力的作用，另一方面提高了MWNTs与Ps之间的相容性，从而提高了MWNTs在Ps基体中的分散性。

Multi-walled carbon nanotubes graft polystyrene copolymers （MWNTs-g-PS） were synthesized by emulsion grafting polymerization. These MWNTs-g-PS copolymers were then blended with polystyrene to prepare MWNTs-g-PS/PS composites. confirmed the gtafting reaction between PS and Fourier transform infrared spectroscopy （FTIR） results MWNTs. Transmission electron microscopy （TEM） photographs showed PS were grafted on the MWNTs effectively and distributed evenly. Through studying the thermal properties, pure multi-walled carbon nanotubes had a good thermal stability with almost no weight loss. The weight loss of MWNTs-g-PS from 100 ~C to 500 ~C was formed due to the thermolysis of PS. Moreover, the dispersion was observed by scanning electron microscope （SEM）, and the result showed MWNTs-g-PS had a much better dispersion in PS matrix compared with pure MWNTs. This was because of the grafting of PS on MWNTs： on the one hand, the Van der Waals force between the molecules of carbon nanotubes was overcame, on the other hand, the compatibility between the MWNTs and PS was improved, which improved the dispersion of MWNTs in PS matrix.