Beta crystal polypropylene tensile expandable material and preparation method thereof

Abstract

The invention discloses a beta crystal polypropylene tensile expandable material and a preparation method thereof. N,N'-dicyclohexyl-2,6-naphthalenedicarboxamide (DCNDCA) is used as a single beta crystal nucleating agent of isotactic polypropylene, and the adding amount of the DCNDCA is more than 0 and not more than 2 percent of the mass of the isotactic polypropylene. The nucleating agent and the isotactic polypropylene are blended by multiple modes of melt blending, solution blending and the like, so that the nucleating agent is uniformly dispersed in the polypropylene material. The material shows tensile expandable property in a certain strain range; and the tensile expandable property of the material is conveniently and flexibly controlled by formation control of polypropylene beta crystal, so that an alternative raw material with flexibility, convenience for making and high economical efficiency, isotropy and mechanical strength is provided for design and manufacture of more tensile expandable material products, the category of the domestic tensile expandable material is enriched, and support is provided for wider application of the tensile expandable material.

Description

technical field [0001] The invention relates to a polypropylene material and a preparation method thereof, in particular to an auxetic material mainly composed of polypropylene and a preparation method thereof. Background technique [0002] Stretch expansion materials, or negative Poisson's ratio materials, sometimes referred to as auxetic materials, are relative to some common materials that are usually familiar to people, such as ordinary rubber materials, whose Poisson's ratio (definition The ratio of negative transverse strain to axial strain) is about 1 / 2. When stretched (or compressed) in a certain direction, this type of ordinary material will shrink (or expand) in the direction perpendicular to it. . Stretch-expandable materials have significantly different or opposite characteristics. Its Poisson's ratio is negative. When stretched (or compressed) in a certain direction, it will expand (or shrink) in a direction perpendicular to it. [0003] In fact, according to ...

AI Technical Summary

Problems solved by technology

For example, the strength of some tensile expansion materials based on polymer microcellular structure is low, while the flexibility of some tensile expansion materials based on cellular structure or crystal structure of metal materials or non-metallic materials is insufficient, through polymer blending Or some tensile expansion materials obtained by compounding often lead to a relative decrease in the mechanical strength of the material due to the existence of the interface

In addition, it should also be noted that the anisotropic characteristics of some tensile expansion materials will limit their applications, and the preparation techniques of many tensile expansion materials are also relatively complicated.

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