The order of feeding is improper during mixing, which affects the uneven dispersion of the compounding agent, and the scorching, de-rolling or over-refining of the compounding agent. Therefore, the feeding order is one of the important factors related to the quality of the rubber compound, so the feeding must have a reasonable order of.

The determination of the feeding sequence generally follows the principle of adding small amount, large effect, difficult to disperse the compounding agent, adding more amount, easily dispersing the compounding agent, adding the temperature sensitive compounding agent, and separately adding the vulcanizing agent and the accelerator.

Therefore, when mixing the mill, the first addition of raw rubber, reclaimed rubber, masterbatch and other wrapping rolls, if there is a solid softener such as paraffin in the formula, can be added after the rubber roll, and then add small materials such as activator (zinc oxide, stearic acid), accelerator, anti-aging agent, anti-scorching agent, etc., add carbon black, filler, add carbon black and filler, add liquid softener, if carbon black and liquid softener When the dosage is large, the two can be added alternately, and finally the vulcanizing agent is added.

If there is an overspeed accelerator in the formulation, it should be added at the end with the vulcanizing agent. If there is white carbon black in the formula, the surface of the white carbon black is highly adsorbed, and hydrogen bonds are easily formed between the particles, which are difficult to disperse. It should be added before the small material, and it should be added in batches. For NBR, since sulfur is poorly compatible with it and is difficult to disperse, it is necessary to add the accelerator in the small material to the final addition before the small material.