Bardash L. Synthesis and study of nanostructured polymer composites based on heterocyclic esters and carbon nanotubes

The object of the research - obtaining of new nanostructured polymeric composites by in situ synthesis of polymers with oligomeric heterocyclic esters containing a filler. The aim of the study is to develop the methods of synthesis of heat-resistant polymer nanocomposites from oligomers of heterocyclic esters of different chemical structure in the presence of multiwalled carbon nanotubes (MWCNT) and to establish a relationships between the conditions of synthesis, composition and viscoelastic, thermal-physical, thermal and electrical properties of the nanostructured materials obtained. Methods: Fourier Transform Infra-Red spectroscopy; melt rheometry, Raman spectroscopy; Scanning Electron Microscopy, Transmission Electron Microscopy; Differential Scanning Calorimetry; Dynamic Mechanical Thermal Analysis; Thermogravimetric Analysis, etc. For the first time, the optimal conditions of synthesis of novel thermostable nanostructured polymer composites from oligomers of cyclic butylene terephthalate (CBT) using method of reactive extrusion and from oligomers of dicyanate ester of bisphenol A (DCBA) using method of reactive forming in the presence in reactive mixture of effectively dispersed MWCNT, were determined. For the first time, catalytic effect of carbon nanotubes in reactions of Ring-Opening Polymerization of CBT oligomers (synthesis of poly(butylene terephthalate), PBT) and polycyclotrimerization of DCBA oligomers (synthesis of polycyanurate network, PCN) have been established. It has been determined that the percolation thresholds for conductivity for the obtained nanocomposites is low and equal to 0.22 wt. % for cPBT/MWCNTs and 0.38 wt. % for PCN/MWCNTs, thus for these nanocomposites the possibility to change the electrical properties in wide range by varying the MWCNTs content has been established. The practical significance of the work is the possibility of creation of nanomaterials of improved mechanical and thermal characteristics, conductors or insulators (depending on CNTs content), applicable as adhesives, coatings or matrixes in airspace industry, microelectronics, etc.