Studies on effect of ethyl 4-amino cinnamate functionalized multiwall carbon nanotubes (f-MWCNTs) on properties of millable polyurethane rubber (MPU) nanocomposites

摘要

Multiwall carbon nanotubes (MWCNTs) were prepared using chemical vapor deposition (CVD) technique in presence of nano Co/Mo-MgO as an efficient catalyst. Further the as-synthesized MWCNTs were functionalized using ethyl 4-amino cinnamate (f-MWCNTs) to improve its wettability or compatibility with the chains of polymer. The as-synthesized MWCNTs and f-MWCNTs were subjected to various characterization techniques Raman spectroscopy, X-ray diffraction, FTIR, FESEM and TGA to investigate its size, presence of functional groups and stability. It was observed that diameter of f-MWCNTs were found to be ～ 45 nm with thermally more stable. Further, f-MWCNTs (0 to 1 ) were reinforced in MPU rubber using two roll mill and molded on compression molding machine. The dumbbell shape specimens were then subjected to mechanical and thermal study. It was observed that both the tensile strength and elongation at break of MPU nanocomposites increases significantly up to 0.8 wt loading and decreases thereafter. This improvement in properties was due to uniform dispersion of f-MWCNTs into the chains of MPU rubber with homogeneity in bonding, while the decrement in properties at 1wt loading was due to agglomeration of f-MWCNTs at some places. Also the functionalization using ethyl 4-amino cinnamate increases the compatibility of MWCNTs with MPU rubber chains. Besides this, functionalization makes the surface of MWCNTs smooth with enhancement in bonding between the two surfaces that is filler as well as matrix counterpart. Significant improvement in mechanical and thermal properties are achieved due to modification MPU with functionalized MWCNT.