The Influence of Conductive Carbon Blacks on Rubber Properties Distributor of Ensaco Products The Influence of Conductive Carbon Blacks on Rubber Properties - New Developments & Applications -

Conductive Carbon Blacks Structure Main carbon black properties Surface Area Surface Quality Rheological Mechanical Electrical properties Main rubber properties

Conductive Carbon Blacks High Structure CB aggregate High ‘void volume’ High ‘DBP absorption’ DBP > 170 ml/100g

Conductive Carbon Blacks High Structure other parameters being similar Longer incorporation times Easier ultimate dispersion Better surface finish Higher extrusion speed Higher Mooney viscosity Lower cure time Higher hardness Higher modulus Lower tensile and tear strengths More compounding flexibility Higher conductivity at lower loading

Conductive Carbon Blacks High Structure Blacks bring Higher Conductivity at Lower Loading +CB Conductive Network ++CB e- CONDUCTOR Polymer _ + ! e- rv ~ 108 - 100 Ohm ·cm ? e- Polymer INSULATOR + _ rv ~ 1012 - 1014 Ohm ·cm All CB … but ...

Conductive Carbon Blacks High Structure Blacks bring Higher Conductivity at Lower Loading ‘Structure-Volume SV ’ equivalency * SV= j * (CDBP+24) r [W*cm] CB % 105 1015 10 20 30 Percolation Curve SV r jc * G. Kraus, J. Polymer Sci., 13, 8, 601 (1970)

Conductive Carbon Blacks As high structure blacks take up more space/volume, one can achieve the same filling level and consequently the same conductivity at a lower concentration

Conductive Carbon Blacks Structure Main carbon black properties Surface Area Surface Quality Rheological Mechanical Electrical properties Main rubber properties

Conductive Carbon Blacks High Structure & High Surface Area ‘Furnace Process’ porosity High Structure & Low Surface Area ‘MMM Process’ - ENSACO™ no porosity

Conductive Carbon Blacks High Structure & Low Surface Area Good dispersibility and excellent ultimate dispersion better mechanical performance and smoother surface finish tend to minimize curing time reduced inhibition of cure agents temper the viscosity increase imparted by the high structure

Conductive Carbon Blacks

Conductive Carbon Blacks

Conductive Carbon Blacks Structure Main carbon black properties Surface Area Surface Quality Rheological Mechanical Electrical properties Main rubber properties

Conductive Carbon Blacks Surface Quality A high oxygen content inhibits cure agent and increase cure time A high graphitization favors electrical conductivity thermal conductivity ENSACO™ - ‘MMM Process’ TOF-SIMS surface analysis: VERY LOW O― CONTENT RX Crystallographic analysis: HIGH GRAPHITIZATION

Conductive Carbon Blacks Some Rubber Applications BELTS: conveyor belts, transmission belts... HOSES: fuel hoses, discharge hoses… PROTECTIVE COATINGS, LININGS... FLOORING POWER CABLES: easy strippable, insulator and conductor shielding... FOOTWEAR: shoe sole... AUTOMOTIVE INDUSTRY: fuel injection systems... HEALTH: surgical tubing... SAFETY: safety systems for windows & doors ROLLERS: printing rolls... SEALS: o-rings, pipe gaskets... CEMENTS & PUTTY HEATING ELEMENTS PTC SWITCHES ANTICORROSION SYSTEMS Engine mount ANTI-VIBRATION SYSTEMS ...

Conductive Carbon Blacks Incorporation in an unlimitted number of elastomers and elastomer blends

Practical Applications Conductive NEOPRENE conveyor belt cover compounds NBR conductive hose compounds FKM conductive compounds NR engine mount / anti-vibration system

Conductive Carbon Blacks HS & High SA HS & Low SA

Practical Applications Conductive CR Conveyor Belt Cover Compound 30 phr

Practical Applications NBR Conductive Hose Compounds 25 phr

Practical Applications FKM (Fluoroelastomer) Conductive Compounds Experimental data provided by DuPont Dow Elastomers, Japan

FKM Conductive Compounds rejected Lower Mooney Viscosity

FKM Conductive Compounds Cured properties: 177°C / 10 min Shorter Vulcanization Time

FKM Conductive Compounds Same Volume Resistivity

FKM Conductive Compounds Lower Compression Set

FKM Conductive Compounds Higher Moduli

FKM Conductive Compounds Higher Tensile Strength

FKM Conductive Compounds Lower Elongation at Break

FKM Conductive Compounds Same Hardness

FKM Conductive Compounds High Structure & Low Surface Area Carbon Blacks enable to compound and make Viton® A conductive (20 phr) Special thanks to DuPont Dow Elastomers, Japan

Practical Applications NR engine mount / anti-vibration system Ensaco 150 G Medium-high structure black with a VERY LOW surface area DBP = 165 ml/100g BET = 44 m²/g required hardness and modulus at low loading higher rebound / lower hysteresis excellent resistance to fatigue / dynamical properties: lower storage modulus much lower tangent delta

Carbon Black Conduction Mechanisms N. Probst, E. Grivei, Third International Conference on Carbon Black, Mulhouse (F), Proceedings 171-176 (10/2000). Conductive CB ’s build a ‘ network ’ at low concentration the ultimate conductivity depends on the DBP at a given pressure the contact resistance low [O-] content ==> pure CB ’s ==> [CB + polymer]

Carbon Black Conduction Mechanisms N. Probst, E. Grivei, Third International Conference on Carbon Black, Mulhouse (F), Proceedings 171-176 (10/2000).

Carbon Black Conduction Mechanisms CB as such, in air 0.4 0.35 0.3 0.25 Resistivity (W·cm) 0.2 0.15 0.1 0.05 100 200 300 400 500 Pressure (kg/cm 2 ) No Significant Difference

Carbon Black Conduction Mechanisms CB as such, in air 0.4 0.35 0.3 0.25 Resistivity (W·cm) 0.2 0.15 0.1 0.05 0.2 0.4 0.6 0.8 1 1.2 1.4 3 Density (g/cm ) Clear Differentiation of Conductive Carbon Blacks

Carbon Black Conduction Mechanisms CB in polymer versus CB as such, at the same VOLUME fraction >> jc ‘ tunneling ’ / polymer film between the CB particles 100 SBR, NR... crystalline elastomers 10 Resistivity in Polymer (W cm) polyolefins 1 ‘ direct contact ’ between the CB particles 0.1 0.1 1 10 Resistivity in Air (W·cm)

Conductive Carbon Blacks Another vision of conductive CB networking New generation of compounds More compounding flexibility Higher conductivity at lower CB loading Another combination of properties Rheological Cure Compounding Mechanical Dynamical Electrical