Method of preparing pipe by double-melting-point composite film

Abstract

The invention discloses a method for preparing a pipe by a double-melting-point composite film. The double-melting-point composite film comprises an upper surface layer, an interlayer and a lower surface layer which are combined together. Each of the upper surface layer and the lower surface layer is a PE layer or a first PET layer, the interlayer is a second PET layer, and the melting point of the first PET layer is lower than that of the second PET layer. When the pipe is prepared, the double-melting-point composite film is wound around a pipe die along a spiral line to form a pipe-shaped winding shell, the winding shell is heated, the upper surface layer and the lower surface layer are molten, seep into and cover all winding overlapped positions of the winding shell, and after cooling, demolding is conducted, and the pipe with the surface with the good sealing effect is obtained. According to the method, the high-melting-point PET is a framework, the pipe is prepared by the double-melting-point composite film with the low-melting-point PET or PE as the skin layer, and the cost is low; and by means of the double-melting-point composite film, the higher modulus and the modulus of stretch are reached through bidirectional stretching, and the strength of the pipe is higher.

Description

technical field [0001] The invention relates to the field of pipe material preparation, in particular to a method for preparing pipe material by using a double-melting point composite film. Background technique [0002] In the prior art, pipes are usually injection-extruded from plastic materials such as PVC, PP, PB or PA. Since these plastics are not stretched to achieve a higher modulus, the strength of the pipe is relatively low. In order to improve the strength of the pipe, it can usually only be achieved by increasing the wall thickness of the pipe, thus increasing the production cost. The cost of PET is low, and people are discussing the direction of using PET to make pipes. Since PET cannot be directly injected into pipes, it must be modified before it can be used for injection pipes, which also increases production costs. Contents of the invention [0003] The purpose of the present invention is to provide a method for preparing pipes with double melting point com...

AI Technical Summary

Problems solved by technology

The cost of PET is low, and people are discussing the direction of using PET to make pipes. Since PET cannot be directly injected into pipes, it must be modified before it can be used for injection-molded pipes, which also increases production costs.

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