Datasheet: Absorptometer-C

The oil absorption number of carbon black is directly related to the processing and vulcanization properties of the rubber compounds prepared with these carbon blacks.

The industry renowned BRABENDER® Absorptometer "E" for running precise and reproducible absorption tests has now been retouched in order to fully meet ASTM D 2414 including new procedures B and C as well as ASTM d 3493.

A maximum torque (saturation) is reached, followed by a state change from liquid into solid to solid into liquid.

In contrast to former Absorptometer models, the instrument and burette no longer automatically stop -- enabling evaluation acc. to the new procedures B and C of ASTM 2414.

INSTRUMENT DESCRIPTION
The Absorptometer "C" Data Acquisition System comprises the following major components:

• Frequency inverter drive unit with precise torque measurement
• High-precision measuring mixer with special blades
• Cooling jacket with temperature indication for mixer (option)
• High-precision burette, sequencer controlled titration rate for optimum test procedure
• 32-bit software for Windows 98, ME, XP, and 2000

THE PRINCIPLE
The principle consists in measuring the resistance which the carbon black puts up against the rotating blades during oil addition and in determining the carbon black absorption. The highprecision burette adds liquid as a titrant to the powder sample in the mixing chamber.

As the liquid wets the sample, three distinct phases can be observed in the torque curve:

• Free flowing phase
• Agglomeration phase
• End phase

During the free flowing phase, liquid is absorbed into the structure of the carbon black. Upon absorption of sufficient liquid, the particles begin to adhere to each other and form agglomerates. Resistance to mixing rises, indicated by a sharp increase in torque.

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