Plasticizing is a processing process that changes rubber from an elastic state to a certain plastic state. Properly masticated rubber, the compounding agent is easily mixed into the rubber compound during mixing, which is convenient for calendering and extrusion. The pattern of the molded product is clear and the shape is stable. It is worth noting that styrene-butadiene rubber, cis-butadiene rubber, and isoprene rubber have been adjusted to the viscosity value during manufacture, and usually do not need to be masticated; neoprene generally does not need to be masticated separately, as long as 3-5 thin passes are passed. Direct mixing is possible.