The Chemistry of Carbon Black in Rubber Reinforcement

Abstract

1. The removal of chemisorbed oxygen from channel black and furnace black, without alteration of the underlying carbon surface, results in only minor effects in reinforcement potential regardless of the curative system employed, whether polar or free radical. 2. When the underlying carbon surface is changed by heat treatment to a state of lower energy, a significant decrease in the reinforcing ability of the carbon black results. 3. Different types of oxygen functional groups added to the carbon surface produce similar effects upon rubber properties. 4. These effects are limited to retardation of cure rate in sulfur curing systems. Only small effects of any kind are produced in the natural rubber-peroxide system. 5. The net conclusion to be drawn is that combined oxygen on the carbon surface plays a relatively minor role in the chemical effect of carbon black upon reinforcement; the nature of the carbon surface itself is of primary importance.

Reinforcement of Elastomers by Particulate Fillers

“…The change is accompanied by formation of a more regular graphitic crystal structure and by the disappearance of active sites for chemisorption. some 30-35% faster than treads containing the precursor black [27,28]. Table I shows results of one of several reported studies with graphitized carbon blacks [26], all of which are in excellent agreement.…”

Effects of Oxidation of Carbon Black Surface on the Properties of Carbon Black–Natural Rubber Systems

“…The compoite was cut into small pieces (about 2 mm in diameter) approximately 2 g of which was loosely packed in a cage of 150 mesh size. The cage was immersed in a sufficiently large amount of toluene (about 400 cm 3 ) and extraction was carried out at room temperature for 72 h. There was no indication of leaching out of the carbon black during the extraction. The carbon gel was suspended in acetone to exchange the toluene with the more volatile solvent and then filtered.…”

“…Tzu and fe was found in other carbon gel samples prepared from the composites of various kinds of oxidized carbon blacks (Carbon Black No. [2][3][4][5][6] with natural rubber. Therefore, the Tzu Tzo and fractions of loosely and tightly bound rubber components at 40°C (reference temperature) were used to evaluate the bound rubber structure.…”

Effect of modified carbon black on the filler–elastomer interaction and dynamic mechanical properties of SBR vulcanizates

“…There was an early report that the treatment of carbon black played a prominent role toward the abrasion resistance. 19 It has come to an agreement that abrasion resistance of filled compounds is mainly determined by morphology of carbon black and polymer-filler interaction. Because of the similar morphology of the two kinds of carbon black, the higher filler-elastomer interaction of vulcanizate employing GCB contributes to the higher abrasion resistance.…”