Principle twin-screw extruder, introduced first twin-screw extruder has a single screw extruder principle extruder: solid conveying melt mixing and pumping pressurized stripping and devolatilization, but do not be so simple. Twin screw extrusion theory study started late, along with its many types, screw geometry complex, complicated extrusion process, which has brought many difficulties to study. On the whole study of twin-screw extrusion theory yet in the initial stage, which is called "art than science" from the study of its extrusion process, about three aspects:

  1, the polymer material during the extrusion process changes of state, transport conveying truth and law principles exhaust solid melts, and establish a physical model of mathematics, used to guide the design of a twin-screw extruder and extrusion process Optimization.

  2, to figure out two or more polymers and materials during the extrusion phase change real situation, hybrid form, the process of structural change, and the relationship between the performance of the final mixture.

  3, as the twin-screw extruder, extrusion reaction process intrinsically linked reaction molding, speed, performance and screw configuration, operating conditions between the model used to guide reaction molding extrusion.