Nanocomposites and nanomaterials

Morphology and physicomechanical properties of antifriction polymer nanocomposite
Havrylova V.S.1, Zhyltsova S.V.2, Mаmunia Е.P.3, Babkina N.V.3, Tkach V.M.1
1 V. Bakul Institute for Superhard Materials, Natl. Acad. of Sci. of Ukraine, Avtozavodska, 2, Kyiv-04074, Ukraine 
E-mail: vsgavrilova@gmail.com
2 Vasyl’ Stus Donetsk National University, vul. 600-richchia, 21, Vinnytsia-21021, Ukraine
3 Institute of Macromolecular Chemistry of the NAS of Ukraine, 48, Kharkivske Shosse, Kyiv-02160, Ukraine

The formation of the nanostructured state of technological polymer coatings is an effective way to achieve a high level of their physical, mechanical and antifriction properties. To obtain coatings with improved adhesion and cohesion properties, the nanodisperse organosilicon modifier synthesized in situ by the sol-gel method was introduced into a matrix based  on anhydride cured epoxy resin. Molybdenum disulfide was added to improve the mechanical and antifriction properties.
The data obtained by scanning electron microscopy indicate a homogeneous single-phase structure of the initial polymer. The introduction of the modifier causes the formation of regions with a pronounced layered morphology, and the addition of MoS2 leads to a decrease in the grain size of the matrix and the formation of a heterophase laered structure with a uniform distribution of phases. This significantly improves the mechanical properties of the nanocomposite.
The results of TMA and DMA methods indicate that the incorporation of 1 wt. % of modifier leads to plasticization of the composite, which is expressed in a decrease in the glass transition temperature caused by a decrease in the effective crosslink density of the epoxy-anhydride matrix. At the same time, this results to the increase of: : tensile strength of the adhesive joints of the composite with D16 aluminum alloy – by 35%, stress at break – by 14%, Young's modulus – by 17%.
When MoS2 is added to the specified composition, the value of the highly elastic deformation of the composite decreases by 46%, the dynamic modulus of elasticity increases by 48%, and the mechanical loss tangent decreases by 15%.
The developed antifriction nanocomposite is a promising coating for friction pairs.