CO2 multi-component cooperative foaming and combined cooling screw rod

Abstract

The invention provides a CO2 multi-component cooperative foaming and combined cooling screw rod which comprises a screw rod body, wherein the screw rod body is sequentially composed of a leakage-proof section, a pressurization section, a low shearing section, a large-lead multi-thread reversely-slotted reflux section, an intensive cooling and mixing section and a multi-thread slotted intensive mixing section from back to front. The screw rod provided by the invention can be used for continuously and stably producing CO2 foaming XPS (extruded polystyrene) sheet materials and solving the problems that large and irregular bubbles exist and the sheet materials can not be continuously produced by a method of producing the XPS sheet materials on a CFC foaming PS screw rod.

Description

technical field [0001] The present invention relates to a CO 2 The multi-component synergistic foaming mixing cooling screw belongs to the plastic processing equipment of polymer materials. Background technique [0002] At present, most domestic plastic physical foaming enterprises use HCFC22 or 142B as foaming agent. Because it contains fluorine and chlorine molecules, it has a certain destructive effect on the atmospheric environment and the ozone layer. According to the "Montreal" agreement, developing countries should gradually reduce and freeze their production before 2030, and this product has been banned in developed countries, CO 2 Foam technology will become an ideal substitute for HCFC, CO 2 Foamed PS materials are very sensitive to pressure, temperature, and shear force. The screw of HCFC foamed PS has no booster section, the pressure is low, the material stays for a long time, the shear force is large, the screw has less grooves, and the mixing and cooling The...

AI Technical Summary

Problems solved by technology

According to the "Montreal" agreement, developing countries should gradually reduce and freeze their production before 2030. In developed countries, this product has been banned. CO2 foaming technology will become an ideal substitute for HCFC , CO2 foamed PS material is very sensitive to pressure, temperature, and shear force. The screw of HCFC foamed PS has no booster section, the pressure is low, the material stays for a long time, and the shear force received The force is large, the screw has less slots, the mixing and cooling effect is poor, and the normal and stable production cannot be performed.

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