Brochure: Carbon Additives for Polymer Compounds - Timcal Graphite

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Conductive carbon black is used in semicon
compounds for conductor and insulator shields.
The requirements for those compounds are besides
processing, a sufficient electrical conductivity,
a smooth or even supersmooth surface
finish, and high purity.
For strippable or easy strippable compounds
these requirements are added to a specific adhesion
strength between the insulating layer
and the insulator shield. These strippable or
easy strippable layers have to peeled of by hand
or using a specific peeling device.
Typical polymer compositions are polyolefins or
copolymers; for strippable compounds quite often
blends of EVA and NBR are used.
TYpICAL EvA/nBR STRIppABLE CoMpoundS
Compound
n-472
Compound
EnSACo® 210
TYpICAL EEA/EBA SEMICon CoMpoundS
Compound
EnSACo® 250
Levaprene 450 90 90 90
Perbunan NT 8625 10 10 10
Rhenogran P60 3 3 3
N-472 40
E 210 40
E 250 40
N-550 40 40 40
Antilux 654 10 10 10
Zn Stearate 1 1 1
Rhenovin DDA-70 1.4 1.4 1.4
Rhenofit TAC/CS 4.3 4.3 4.3
Percadox BC-408 5 5 5
Viscosity ML (4+1) 56 44 48
Rheometer@180 t90% 3.6 3.6 3.8
Mechanical properties
Non aged (diff. aged)
Tensile strength MPa 16.5 (-19) 16.9 (-15) 16.9 (-15)
Elongation at break % 215 (-58) 180 (-50) 170 (-53)
Modulus 100% MPa 11 12.2 12.7
Shore A 87 (+7) 90 (+4) 89 (+7)
Peel strength hot air 100°C N
- after 3 days N
- after 21 days N
Volume resistivity (Ohm.cm) 210 6600 410
7
5
5
3
4
3
Compound
EEA
EEA 100
4
3
4
Compound
EBA
EBA 100
E 250 30 30
Peroxide
Mixing cond. L/d15; Feed BC; Truput 30
Resistivity @ RT 7.2 5.6
Resistivity @ 90°C 37 22
Carbon black dispersion: