Brochure: Carbon Additives for Polymer Compounds - Timcal Graphite

TYpICAL AppLICATIonS FoR EnSACo® ConduCTIvE CARBon BLACk
EnSACo® ConduCTIvE CARBon BLACkS In LdpE
Infl uence of the carbon black type and of the
MFI of the starting polymer on the resistivity
Compounding: laboratory Brabender internal mixer.
Processing: compression moulding.
The higher the structure of the carbon black,
the lower the percolation threshold.
At equal structure, the carbon black of lower
surface area gets an advantage on resistivity
that may be coming from the easier dispersion
resulting in smoother compounding. The higher
the meltfl ow index of the starting polymer, the
lower the percolation threshold.
EnSACo® ConduCTIvE CARBon BLACkS In pp
Infl uence of the carbon black type on the
resistivity. Relation between resistivity and
melt fl ow index
Compounding and processing: twin screw extruder Haake PTW16
and realization of tapes.
At same structure level, the carbon black with
the lowest surface area has the smallest impact
on fl uidity reduction.
Infl uence of carbon black loading and
processing on the resistivity
Compounding: ZSK25 twin screw extruder.
Processing: injection moulding.
Injection moulding generates more shear than
compression moulding. The closest to the percolation,
the more visible is that eff ect. A concentration
safety margin can overcome this
phenomenon.
12
various carbon black in LdpE MFI 0.3 and 36 (g/10 min)
Volume Resistivity [Ohm.cm]
Volume Resistivity [Ohm.cm]
Volume Resistivity [Ohm.cm]
10 8
10 6
10 4
10 2
10
0 5 10 15 20 25 30 35
0
10 4
10 3
10 2
10 1
10 0
10 6
10 5
10 4
10 3
10 2
10 1
10 0
Carbon Black Concentration [%]
ppH MI54 (230 °C/5 kg) with various conductive carbon blacks
0 10 100
171
MFI [230 °C/5 kg] [g/10 min]
24
10
6
4.6E + 10
strands pellets + pressed pellets +
plaques injection moulding
54
E250 G LD 0.3
E250 G LD 36
N472 LD 0.3
N472 LD 36
P-type LD 0.3
P-type LD 36
E250 G
high structure
low surface area
N472
high structure
high surface area
13.50% E250 G
15% E250 G