Single-screw extruder barrel structure for ultra-high molecular weight polyethylene

Abstract

The invention discloses a single-screw extruder barrel structure for ultra-high molecular weight polyethylene, belongs to the technical field of extrusion of ultra-high molecular weight polyethylene,and provides a barrel structure capable of driving a screw of an extruder to continuously and stably convey ultra-high molecular weight polyethylene to the direction of an extruder head and guaranteeing extruding quality. The barrel structure comprises a barrel body, wherein the barrel body comprises a feeding section, a compression section and a molten pool section which are sequentially connected in the material extruding direction; a drum cavity is formed in the molten pool section; and a plurality of bulging convex dam structures are distributed on corresponding inner walls of the compression section and the molten pool section at intervals respectively. With adoption of the barrel structure, stable extrusion of ultra-high molecular weight polyethylene can be realized by the corresponding extruder, furthermore, compacted of ultra-high molecular weight polyethylene melt is sufficiently relaxed in the drum cavity of the molten pool section, so that internal stress of the melt is eliminated, and finally, quality of an extruded product of ultra-high molecular weight polyethylene is improved.

Description

technical field [0001] The invention relates to the technical field of ultra-high molecular weight polyethylene extrusion, in particular to a barrel structure of a single-screw extruder for ultra-high molecular weight polyethylene. Background technique [0002] UHMWPE is used as the viscosity average molecular weight (M η ) is a thermoplastic with more than 1.5 million. Because of its extremely regular, non-polar and ultra-long molecular chain structure, UHMWPE has many unique properties, including excellent impact resistance and wear resistance. properties, excellent mechanical strength and good biocompatibility, etc. However, the unique molecular structure of ultra-high molecular weight polyethylene also brings great difficulties and challenges to its processing and application. There are a large number of crossings and entanglements between ultra-long molecular chains. Above the melting point, it is also difficult to completely remove it. Macroscopically, it shows that ...

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Problems solved by technology

However, these methods have their own shortcomings and defects, and cannot completely solve the processing problems of ultra-high molecular weight polyethylene: the preparation of ultra-high molecular weight polyethylene with low entanglement requires the development of new synthesis methods and processes, high cost and harsh synthesis conditions , the output is low, and it is difficult to realize industrial production; although adding a flow modifier can reduce the viscosity of UHMWPE, the presence of the flow modifier as an impurity in UHMWPE will affect the performance of the material itself, making UHMWPE The superior and unique properties of high-molecular-weight polyethylene are difficult to bring into play; although the production of ultra-high-molecular-weight polyethylene products by compression molding can effectively solve the problem of difficult flow, compression molding takes a long time and is difficult to achieve continuous production. Both greatly limit the production efficiency of the product, and for thick-walled products, the heat transfer speed of the compression molding method to the inside of the thick-walled product is slow, and it is easy to form raw materials that have not been plasticized inside the product, which greatly affects The quality and performance of the products are improved; although the gel spinning process successfully solves the spinning problem of ultra-high molecular weight polyethylene and realizes industrial production, it cannot meet the requirements for the preparation of large-scale products or various types of materials such as pipes and rods. requirements, and a large amount of organic solvent decahydronaphthalene needs to be used in the jelly spinning process, which not only increases the production cost, but also causes serious pollution to the environment

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