TITLE:
Carbon Nano Material Synthesis from Polyethylene by Chemical Vapour Deposition
AUTHORS:
Pravin Jagdale, Madhuri Sharon, Golap Kalita, Noor Mahmad Nabi Maldar, Maheshwar Sharon
KEYWORDS:
Polyethylene; Pyrolysis; LDPE; HDPE; LLDPE; Carbon Nano Material (CNM); Carbon Nano Beads (CNB); Carbon Nano Tubes (CNT)
JOURNAL NAME:
Advances in Materials Physics and Chemistry,
Vol.2 No.1,
March
19,
2012
ABSTRACT: Three different types of Polyethylene family, High Density Polyethylene, (HDPE), Low Density polyethylene (LDPE) and Linear Low Density polyethylene (LLDPE) polymers having different molecular weight and density; were pyrolyzed in the temperature range of 550°C - 1050°C under H2, N2 and Ar gases. Taguchi Optimization technique was applied to find out the best operating conditions to get maximum yield of carbon nano material (CNM). For Taguchi op- timization, experimental set up was done in two different temperature ranges i.e. 550°C - 750°C and 850°C - 1050°C. CNMs synthesized were characterized by SEM, TEM, Micro Raman and XRD analysis. HDPE was found to yield maximum CNM. Its pyrolysis at 750°C under hydrogen atmosphere for 2h gave carbon nano beads and some carbon nano tubes. Whereas under same conditions at 1050°C more multi wall carbon nano tubes (MWCNT) were produced, with some carbon nano beads. XRD data confirmed the graphitic nature of carbon-nanotube. The intensities of G-band and D-band of Raman spectra suggested that CNM has more defect sites and spectra were similar for CNM obtained in both the temperature ranges. The TGA analysis of CNM obtained at 550°C - 750°C, indicated that they are not amor- phous carbon and CNM obtained at 850°C - 1050°C decomposed at 624°C - 668°C; suggesting that CNT synthesized at this temperature range were more crystalline than what was obtained at the 550°C - 750°C.