There are many factors that go into nylon toughening, and the key factor is the equipment – the twin-screw extruder is best to choose the right length-to-diameter ratio and high torque. So what are the benefits of a high-torque extruder? It produces one of the best points, that isReduces shear heat
From two aspects, first of all, in nylon toughening, when using a twin-screw extruder to do nylon toughening modification, it can often be plasticized well, rather than providing heat by barrel heating. The shear heat generated during the rotation of the screw is enough to melt and plasticize the nylon.
At this time, it will be found that in the normal production and operation of the twin-screw, in fact, in addition to the first few sections of the 1 to 4 zones, there is heating work, in fact, the cooling is often carried out after the fifth and sixth sections, that is to say, in the process of rotation, it will actually produce a lot of shear heat.
Excessive shear heat is a bad result for nylon materials, and it will lead to the destruction of performance during nylon toughening, resulting in a decrease in performance.
Second, under the three conditions of a certain screw combination, a certain viscosity of the material, and a certain speed of the main engine, when the material passes through a certain area of the extruder, the shear heat it receives is also certain.
If the extruder with higher torque is used, it also means that more material passes through the unit time, so the average shear heat of the material is relatively low, and the shear heat can be effectively reduced in the state of full plasticization and melting, so that the performance of the modified material can be better maintained.
Therefore, when the torque is high, it can bring about a reduction in shear heat.