A 10-a editie a Seminarului National de nanostiinta si nanotehnologie

18 mai 2011 Biblioteca Academiei Romane

The Morphology of Laser-Synthesized Carbon Nano-Fillers: the Influence on Polymer-Based Composites

Lavinia Gavrila-Florescu1*, Ion Sandu1

1National Institute for Lasers, Plasma and Radiation Physics, P.O. Box MG-36, Bucharest, Romania

*IMT-Bucharest, 126A, Erou Iancu Nicolae street, 077190, PO-BOX 38-160, 023573, Bucharest, Romania

Carbon nanoparticles are considered high-potential filler materials for the improvement of mechanical and physical polymer properties; the focus of the work was to drive these materials into a regime where they can favorably interact with the matrix.

MOTIVATION

GENERAL FEATURES OF CARBON NANOPOWDER SYNTHESIZED BY LASER-INDUCED PYROLYSIS

Size depends on gas composition and experimental parameters (10-60 nm) Coalescence in bigger particles. Agglomeration occurs already in the flame.

Bending through the graphite nano-ribbons

MAIN CARBON POWDER MORPHOLOGIES

TURBOSTRATIC (C6H6/C2H4) TURBOSTRATIC (C2H2/SF6) Carbon nano-ribbons (C2H2/SF6) C/F=3 Fullerene-like (C6H6/C2H4/N2O)

TESTS FOR POSSIBLE APPLICATIONS

Laser induced pyrolysis morphologically different carbon nanopowders with specific chemical properties; Experimental confirmation by their particular behavior during interaction with different chemical and biological systems; Electrical conduction of polymer/carbon composite strongly influenced by electrical resistivity of filler

(C/F)at ratio sp2 bonded C [%] Particle size [nm] La [Å] Resistivity*

[X105cm]d002 [Å]

0.8 92.5 19 18.1 5.8 4.45

1.3 94.2 21 18.4 3.5 3.77

3 96.8 30 20.5 4.6 3.58

* sample’s density: 1.2 g/cm3

-0.10 -0.08 -0.06 -0.04 -0.02 0.00 0.02 0.04 0.06 0.08 0.10 0.12-100

-80

-60

-40

-20

0

20

40

60

80

100

I [A

]

U [V]

Ohmic behavior

0.5 1.0 1.5 2.0 2.5 3.01.5

2.0

2.5

3.0

3.5

4.0

4.5

5.0

5.5

cm

] x1

04

C/F

Resistance vs soot structure and morphology

0.5 1.0 1.5 2.0 2.5 3.0

1.8

2.0

2.2

2.4

2.6

2.8

3.0

C/F atomic ratio

1/d002

[nm-1]

La [nm]

1/d002 and La vs (C/F)at ratio

Resistivity vs carbon content

CONCLUSIONS

characteristics of the obtained nanocomposite are affected by properties and dispersion of the addition material; the morphology of the carbon nanopowder depends on both gas mixture and experimental parameters; optimal concentration of the filler was around 2% (wt); better results obtained by addition of laser-synthesized carbon nanopowder; the additional

reinforcement with carbon/glass fibers led to an important enhancement of mechanic characteristics; the studies are in progress.

Acknowledgement: Some of the results were obtained in the frame of the Project POSDRU/89/1.5/S/63700.