Strengthening of mechanical properties of polymethylmethacrylate doped by carbon nanotubes

Polymerization of acrylic monomer in the presence of multi-walled carbon nanotubes, original and functionalized by carboxyl groups, produced new polymer composites with improved mechanical characteristics. The thermal stability of composites based on polymethyl methacrylate doped with carbon nanotubes was studied, and the glass transition temperatures of polymers were determined. The most promising for dispersing carbon nanotubes in monomers are multi-walled carbon nanotubes with a surface functionalized by carboxyl groups. The time of dispersion of nanotubes in monomers to obtain a stable system during ultrasonic processing depends on their percentage in monomer, the structure of the monomer and the viscosity of the medium. The value of ultimate tensile strength of polymethylmethacrylate with an increase in the concentration of nanotubes in the composite increases by 1.8 times, microhardness - 2.1 times compared with the polymer without nanotubes. A significant increase in the concentration of nanotubes leads to a decrease in tensile strength.