Low pressure plasmachemical processing of multi-walled carbon nanotubes for the production of polyurethane composite films with improved mechanical properties

• Published in: Thin solid films Vol. 538; pp. 7 - 15
• Main Authors: ZAJICKOVA, Lenka, ELIAS, Marek, BURSIKOVA, Vilma, STUDYNKOVA, Zuzana, MAZANKOVA, Vera, MICHLICEK, Miroslav, HOUDKOVA, Jana
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Amsterdam Elsevier B.V 01.07.2013; Elsevier
• Subjects: Carbon nanotubes; CCP; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Depth sensing indentation; Exact sciences and technology; FTIR; Materials science; Mechanical and acoustical properties of condensed matter; Mechanical properties of nanoscale materials; Methods of nanofabrication; Nanoscale materials and structures: fabrication and characterization; Nanotubes; Physics; Plasma functionalization; Polyurethane composites; XPS; CCP; Plasma functionalization; Polyurethane composites; FTIR; Carbon nanotubes; XPS; Depth sensing indentation; Composite film; Fourier transform spectroscopy; Deformation; Creep; Gas mixtures; Functionalization; Nanomaterial synthesis; Elastic modulus; Fillers; Polymerization; Mechanical properties; Hardness; Carbon; Indentation; Polyurethanes; Ammonia; Composite materials; Multiwalled nanotube; Low pressure; Nanostructured materials; X-ray photoelectron spectra
• ISSN: 0040-6090; 1879-2731
• DOI: 10.1016/j.tsf.2012.11.126

Multiwalled carbon nanotubes (CNTs) were modified in low pressure capacitively coupled discharges (13.56 and 27.12MHz) in Ar/NH3 and oxygen-containing gas mixtures. A direct functionalization by nitrogen groups was not possible but 1–3 percentage of carbon–oxygen bonds increased with the total oxygen content on the expenses of sp2C almost independently on the plasma conditions. The plasma modified CNTs were used as fillers for polyurethane (PU) composites prepared by in situ polymerization. The composites were investigated by depth sensing indentation that revealed the existence of surface harder layer caused probably by different polymerization process in the bulk and at the surface that was in a contact with air. The significant improvement of the hardness and elastic modulus was observed when plasma-modified CNTs with high amount of oxygen were added to PU. It also improved the creep resistance of the PU, whereas the ability to recover from a deformation, i.e. anelastic recovery, did not change much. ► We functionalized carbon nanotubes in low pressure capacitive discharges. ► Carbon nanotubes (CNTs) can be easily functionalized by oxygen-containing groups. ► We have prepared polyurethane composites filled by plasma-modified CNTs. ► The mechanical properties of the composites were significantly improved.