多壁碳纳米管在聚氨酯基涂覆材料中分散性能的研究

Study on Dispersion Properties of Multi-walled Carbon Nanotubes in Polyurethane-Based Coating Materials

采用混合酸对多壁碳纳米管(MWCNTs)进行处理,得到具有反应性基团的功能化多壁碳纳米管(O-MWCNTs);以聚乙二醇(PEG1000)和异佛尔酮二异氰酸酯(IPDI)为主要原料反应生成聚氨酯(PU)预聚体,然后通过原位复合法制备了PU/MWCNTs、PU/O-MWCNTs复合乳液;通过透射电子显微镜(TEM)、扫描电子显微镜(SEM)、X射线光电子能谱仪(XPS)及红外光谱仪(FTIR)等仪器表征分析了MWCNTs和O-MWCNTs的微观结构、表面形貌和分散性能,并通过FTIR对PU、MWCNTs/PU、PU/O-MWCNTs进行了结构特征分析。结果表明,混合酸处理使MWCNTs侧壁引入了约自身质量10.2%的含氧官能团,极大地提高了MWCNTs在PU基体中的分散性;O-MWCNTs在PU预聚体形成之后加入时,会与PU链嵌段或者接枝,更利于分散;PU/O-MWCNTs复合乳液外观细腻呈黑灰色,静置36 h后O-MWCNTs仍呈现良好的分散性。

Multi-walled carbon nanotubes(MWCNTs)were treated with mixed acid to obtain functionalized MWCNTs(O-MWCNTs)with reactive groups. Polyethylene glycol(PEG1000)and isophorone diisocyanate(IPDI)were used as main raw materials to produce polyurethane(PU)prepolymer,and then the MWCNTs/PU and PU/O-MWCNTs composite materials were prepared through an in-situ composite method. The microstructure,surface morphology and dispersion performance of MWCNTs and O-MWCNTs were investigated using TEM,SEM,XPS and FTIR. The structure characteristics of PU/MWCNTs and PU/O-MWCNTs composites as well as pure PU were characterized by use of FTIR. The results indicated that the treatment with mixed acid introduced 10. 2 % of oxygen-containing functional groups into the sidewalls of MWCNTs. This greatly improves the dispersibility of MWCNTs in the polyurethane matrix. When O-MWCNTs was added with the formation of prepolymers,O-MWCNTs could be grafted into the PU chains. This may facilitate the dispersion more effectively. The PU/O-MWCNTs composite emulsion exhibited a fine and dark aspect,and the O-MWCNTs still presented good dispersibility after standing for 36 h.