A polypropylene composition

Abstract

The invention discloses a polypropylene combination, which comprises the following components in parts by weight: 40-55 parts of copolymerized polypropylene resin, 0-10 parts of low-density polyethylene resin, 5-20 parts of ethylene octene copolymer and 25 parts of talcum powder ~35 parts; the molecular weight distribution of the copolymerized polypropylene resin is ≤4.5. The polypropylene composition of the present invention adopts a copolymerized polypropylene resin with a narrow molecular weight distribution, which can effectively reduce the content of low molecular weight polypropylene in the copolymerized polypropylene, weaken the crystallization tendency of the polypropylene polymer, and reduce the linear expansion of the polypropylene material Coefficient, and the raw materials can be input through the main feeding port, which can be applied to the automobile polypropylene tailgate and polypropylene fender outer panel, to help the automobile lightweight business.

Description

Technical field [0001] The present invention belongs to the field of polymer material technology, specifically relates to a polypropylene composition. Background [0002] Polypropylene (REFERRed to as PP) material has the advantages of low density, good comprehensive performance and low price, which fits the development trend of lightweight and environmental protection in the automotive industry, and is gradually developing new automotive parts application scenarios. As a new branch of the traditional automotive field, the new energy automobile industry has a more pursuit of automobile lightweight, such as the tailgate and fender material of new energy vehicles, which were originally steel or aluminum alloys, and are gradually being replaced by plastic tailgate and plastic fender materials. The biggest advantage of plastic parts for metal parts is that it is lightweight, and the tailgate and fender materials are non-stressed structural parts, which do not encounter large stress o...

AI Technical Summary

Problems solved by technology

However, compared with metal materials, general polypropylene materials have several obvious disadvantages: First, polypropylene materials, as semi-crystalline polymer materials, are prone to dimensional changes in the application environment of alternating cold and heat, and the change range is larger than that of metal materials. The metal is high, and it is easy to cause the assembly gap to be too large, and the assembly parts to interfere with other problems

The second is that polypropylene material needs to be sprayed as a material for the tailgate and fenders of the car to achieve the same appearance as the metal body. If the flow marks that appear during the injection molding process are too obvious, the spraying cannot completely cover them, which will lead to There are obvious flow marks similar to "tiger skin" on the surface, which affects the appearance of the car

[0005] To sum up, there are few reports on polypropylene products and patents for low linear expansion coefficient and good appearance of automobile polypropylene tailgate and polypropylene fender outer panel

Images