“Semiconductor” Model of the “Polymer-CNTs” Composite Strengthening

Abstract

We analyzed “semiconductor” model of the “polymer-CNTs” composite strengthening at 300 K and low (0.1-0.5) wt% CNTs concentration. Carbon nanotubes are among the most anisotropic materials known and have extremely high values of Young's modulus. We investigated influence of vibration bonds on polymer crystallization and strengthening in composite films of polyethylenimine, polyamide, polypropylene and rubber with multiwall carbon nanotubes. IR absorbance maxima we evaluated after formation of composite “polyethylenimine-carbon nanotube” in the spectral area of the sp³ hybridization bonds at the frequency of primary amino groups of polyethylenimine. High IR absorption in the spectral area of sp³ hybridization bonds of polypropylene, polyamide-6 with carbon nanotubes is determined by γ_ω(CН) and γ_ω(CH₂) vibrations. We measured IR reflectance maxima of composite “rubber-carbon nanotube” in the spectral area of CH valence and deformation vibrations. The IR peak dependence on the carbon nanotube content corresponds to 1D Gaussian curve for the diffusion equation in the electric field between electrons of nanotubes and protons in polymer according to “semiconductor” model of the composite structuring. For our case of the long-acting hundreds nanometer interactions, the polymer crystallization depends on sp³ C-C bonds organization in the intrinsic electric field according to the semiconductor n-p model. Tensile strength for polyamide-6 composites at 0.25% CNTs increases 1.7 times and tensile deformation – 2.3 times.