Surface shear plasticization method and device

Abstract

The invention discloses a surface shear plasticization method and device. The device comprises an outer sleeve (1), an inner sleeve (2), a conveying material cylinder (3), a conveying screw (4), a speed reducer (5), a rotating motor (6), sliding guide rods (7), a movable nut (8), a movable lead screw (9), a circulating cooling coil (10), a feeding hopper (11), a movable motor (12) and a heating coil. The inner sleeve (2) is sleeved with the outer sleeve (1). Inner circle grinding discs in the inner sleeve (2) and outer circle grinding discs in the outer sleeve (1) are nested in the opposite directions and not in contact with each other. Annular comb teeth are in butt joint with each other to form surface shear grinding. Materials can pass a gap between the butt-jointed annular grinding disc sleeves and also can pass tooth gaps of the annular comb teeth in turn, the grinding disc gap resistance is lowered, the flowing route of the materials is changed ceaselessly, and the mixing degree of the materials is increased greatly; and the sleeve grinding discs are designed to be with tapered surfaces, and the gaps of the grinding discs can be adjusted by changing the axial distance of the inner sleeve and the outer sleeve.

Description

technical field [0001] The invention relates to a method and device for surface shear plasticization, in particular to the use of comb-shaped butt sleeve grinding discs to form surface shear grinding to achieve the purpose of high-efficiency plasticization, and belongs to the technical field of polymer material forming and processing. Background technique [0002] Good plasticizing quality is a necessary prerequisite for the molding and processing of all polymer materials. The traditional plasticizing methods include two-roll milling, banbury mixing, single-screw or twin-screw mixing, and its basic plasticizing principle is to force the material to form a spatial change, which produces shearing, kneading, dragging, and position-exchanging mixing of the material. effect. That is to say, drag shearing and extrusion deformation kneading, the plasticizing shearing method is not surface shearing, and the common problem is that the shearing effect is weak and the mixing and dispe...

AI Technical Summary

Problems solved by technology

That is to say, drag shearing and extrusion deformation kneading, the plasticizing shearing method is not surface shearing, the common problem is that the shearing effect is weak and the mixing and dispersion are poor

Various improvements have also been made around the screw extruder, such as gradually changing the depth of the screw groove to produce volume compression, and a twin-screw extruder with a kneading unit has also been developed, but the basic structure of the screw or kneading has not changed substantially. ——Kneading and dragging shear plasticization, the plasticizing pressure is only 30MPa

[0006] Injection machines generally use split shuttles or short screws for plasticization, and the plasticization quality is relatively poor

Chinese patent CN201310402782.7 discloses "A New Disc Extruder for Trace Material Blending". The principle is that a disc is added to one end of the screw to achieve surface shear plasticization. The disadvantage is that the gap between the discs is too small and the resistance is large. If the gap increases, the plasticization will be poor; Chinese patent CN201410004634.4 discloses "A Tandem Disc Extruder with Different Diameters and Different Gap Screw Channel Volume Changes", which uses two sections of screws with different diameters in series, and the front section has a large diameter. The screw has a grinding disc for surface shear plasticization, which uses the volume change of the screw groove with unequal gaps for plasticization. The disadvantage is that the two sections of the screw are connected in series, the axial dimension is too large, and the residence time of the material in the barrel is too long, which is easy to last for a long time. thermal decomposition

[0007] Zhou Haiying and others disclosed "A Conical Grinding Disc Extruder" in the journal "China Plastics" (2006, 07:65-68). The disadvantage is that there is a problem of large resistance of the grinding disc gap

Its disadvantage is that if you want to increase the area of ​​the shearing surface of the grinding disc, you need to increase the diameter of the grinding disc, which will lead to an increase in the axial pressure on the grinding disc surface, and if you do not increase the axial pressure, it will reduce the pressure of the material in the grinding disc gap (unit area pressure), on the other hand, the assembly and maintenance of the grinding disc with this structure is very inconvenient, and the assembly accuracy is very high, which increases the maintenance cost

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