Polyamide mold composition

Abstract

The invention discloses a polyamide mold composition, which consists of at least one polyamide resin, glass fiber, hydro-oleophobic master batches, a heat stabilizer and other additives, wherein the melting point of the polyamide resin is between 270 DEG C and 340 DEG C, and the relative viscosity of the polyamide resin, measured by 96 percent concentrated sulfuric acid at the temperature of 25 DEG C, is between 2.0 and 2.4. The composition is prepared by the following steps of: preparing the hydro-oleophobic master batches; extruding and pelletizing; drying and uniformly mixing the obtained hydro-oleophobic master batches with the polyamide resin, the heat stabilizer and other additives by using a high speed mixer; adding the mixture through a main feeding hole of a double screw extruder; adding the glass fiber from a second feeding hole of the extruder; and extruding and pelletizing at resin melting temperature, and drying to obtain a corresponding polyamide mold composition. The invention has the advantages that: 1, the hydro-oleophobic master batches are added into the polyamide resin, so that the physical corrosion resistance and the mechanical property of the polyamide mold composition can be enhanced; and 2, a fluorine-containing copolymer in the master batches is beneficial to the dilution and the dispersion of the fluorine-containing copolymer in the master batches during secondary processing.

Description

technical field [0001] The present invention relates to a polyamide molding composition, and more particularly, to a polyamide molding composition suitable for radiator water tanks of automobiles. Background technique [0002] The radiator is an indispensable and important part in the cooling system of the automobile water-cooled engine. With the continuous increase of the speed and power of the automobile engine, the heat load is increasing, and the requirements for the cooling system are also getting higher and higher. In order to reduce weight, improve corrosion resistance and save non-ferrous metals, in practical applications, the materials of radiator upper and lower water chambers are gradually made of engineering plastics instead of traditional copper materials. Compared with traditional copper materials, plastic water chambers have many advantages such as light weight, corrosion resistance, simple manufacturing process, short molding cycle, low cost, and long life. ...

AI Technical Summary

Problems solved by technology

However, the activity of the active group in the preparation process tends to increase the viscosity of the material during processing, decrease the fluidity, and even produce gel, which requires strict production control; in order to obtain good surface products, it is necessary to increase the amount of flow modifier , and these additives usually reduce the heat resistance and hydrolysis resistance of the material; at the same time, due to the influence of diffusion, the collision probability of the reactive active group and the polyamide end group is also controlled by the position, and its water (alcohol) resistance ) solution needs to be improved