Rubber is deformed by external forces, and when the external forces are removed, the ability of rubber to maintain its deformation is called plasticity. Increase rubber plasticity process is called plasticizing. Rubber has plasticity in order to mix with a variety of matching agents in the mixing evenly; in calendering is easy to penetrate into the textile; in the press out, injection pressure with good mobility. In addition, plasticizing can also make the rubber properties uniform, easy to control the production process. However, the transition of plasticizing will reduce the strength of vulcanized rubber, elasticity, abrasion resistance and other properties, so the plasticizing operation needs to be strictly controlled.  Rubber plasticity is usually expressed in William's plasticity, Menni viscosity and Devereux hardness.

1、Opening machine molding  

The advantage is that the quality of plasticized rubber is good, small shrinkage, but low production efficiency, labor intensity. This method is suitable for more changes in the rubber and less glue consumption of the factory.  Opening machine plasticizing belongs to low temperature plasticizing. Therefore, reduce the rubber temperature in order to increase the force is the key to the opening machine plasticizing. With the temperature and mechanical effects related to the characteristics of the equipment and process conditions are important factors affecting the effect of molding.

2, dense machine molding (high temperature, intermittent)  

Refiner refining production capacity, low labor intensity, low power consumption; but because it is a closed system, so cleaning is more difficult, so only for the occasions of less change in the type of rubber.  Complex structure of the smelter, raw rubber in the smelting chamber on the one hand, between the rotor and the cavity wall by shear stress and friction, on the other hand, also subject to the external pressure on the top of the bolt.

3, screw machine molding (high temperature, side continued)  

Screw molding is characterized by continuous molding at high temperatures. In the screw molding machine in the raw rubber on the one hand by the strong stirring effect, on the other hand, due to the raw use of screw and barrel wall friction produces a lot of heat, accelerated oxidation cracking.