Keywords: polymethylmethacrylate, PMMA, carbon nanotubes, CNT, nanocomposites, vibration spectroscopy, dielectric barrier discharges, DBDs, dental nanomaterials, dielectric nitrogen doping, atmospheric plasma, bonding reconfiguration
Properties of CNT reinforced: PMMA nanocomposites and PMMA treated in NH3-gaseous atmospheric dielectric barrier discharge
Polymethylmethacrylate (PMMA) polymer is a common dental laboratory and clinical material attracting various applications in plastic and adhesive dentistry. In direct contact with cellular tissues, PMMA may have toxic and inflammable properties which may limit use in contact with living dental tissues. By reinforcing PMMA with carbon nanotube and dielectric Nitrogen doping (in ammonia atmosphere), it is believed that the emerging PMMA-CNT nanocomposites could have improved mechanical, chemical and biocompatible properties, improved wear and corrosion resistance, that may not be obtainable with PMMA alone. The exposure to atmospheric plasma seems to play some role in homogenisation of the composites and in increasing matrix-filler interfacial bonding, as several radicals are generated in the plasma atmosphere leading to bonding reconfiguration. Initially, we compared the DBD surface induced properties of PMMA treated in air, ammonia and chloroform atmospheres, and then the properties of the emerging PMMA-CNT nanocomposite. The resulting composite in this preliminary investigation is, however, short of complete homogenisation as evidenced from residues/particles dislodging from the materials surface following exposure to DBD. Thus, further investigation is required in order to obtain an optimal mixture for various applications. The PMMA-CNT was produced by simple sol-gel technique with ultrasonication, and the characterisation of the resulting nanocomposite was achieved by the use of Fourier Transform Infra Red (FTIR) spectroscopy, Raman spectroscopy, X-ray Photoelectron Spectroscopy (XPS), Secondary Ion Mass Spectroscopy (SIMS) and optical contact angle meter.