ИСТИНА

Nowadays one of the most actively developing approaches for improving polymeric materials performance is the creation of composites with carbon nanotubes. Functional groups grafted to nanotubes provide a homogeneous dispersion of the latter in the solvent or polymer and can favor the formation of covalent bonds with the polymer matrix, which substantially affects the properties of the final nanocomposites. Two methods for the modification of single-walled carbon nanotubes (SWCNTs) were proposed: covalent and non-covalent functionalization by polyimides. Aromatic polyimides soluble in ε-caprolactam melt and, moreover, act as ε-caprolactam polymerization activators1.Such modification allows for the preparation of stable nonsagging SWNTs dispersions in the melted ε-caprolactam. These dispersions were further utilized for in situ ring-opening anionic polymerization of ε-caprolactam. Being active in anionic polymerization of ε-caprolactam both types of functionalized SWCNTs allow overcome the weak interfacial interaction between the nanotubes and the polymer matrix as well as promote occurrence of covalent bonds. The modified nanotubes as well as Nylon-6/SWCNTs composites were thoroughly examined by the series of instrumental techniques including thermogravimetric and elemental analysis, XPS, SEM, TMA, mechanical tests, etc. It was shown both methods of nanotubes modification increase the thermal stability; enhance the compression modulus and impact strength of polymer blocks and advance the tensile strength and elongation of polymer films. Obtained composites were used as coatings for optical fibers. These composites as the coatings have high adhesion to the optical fibers, feature sufficient resistance to the aggressive medium and possess a combination of valuable mechanical properties. References 1. [1] T. V. Volkova, Y. S. Vygodskii, O. N. Zabegaeva, et al. Synthesis and characterization of grafted copolymers of aromatic polyimides and ε-caprolactam, Journal of Applied Polymer Science 2009; 114: 577-586. This work was supported by the Russian Science Foundation (Grant No. 14-13-01273).