Why the rubber material will produce too high or too low plasticity?

The main reason for this situation is that the plasticizer plasticity is not appropriate; mixing time is too long or too short; mixing temperature is not appropriate; and with the rubber is not mixed well; plasticizer added more or less; carbon black less or more added or varieties with the wrong and so on will be produced. Improvement is appropriate to grasp the plasticity of the plasticizer, control the mixing time and temperature, and with the rubber needs to be mixed evenly, with the agent should be weighed accurately and strengthen the inspection.