High-filled modified-surface strengthened polyamide composition

Abstract

The invention discloses a high-filled modified-surface strengthened polyamide composition, which consists of semi-aromatic polyamide, aliphatic polyamide, a polycarbonyl compound and an inorganic strengthened filler, and is mainly used in the fields of electronic and electrical appliances, automobiles, furniture, building materials and fibers. The composition has the advantages that: as the polycarbonyl compound is added into a polyamide composition, so the branching reaction of polyamide in a melt extrusion process can be performed to obtain branched polyamide, and the composition of the branched polyamide has high mechanical performance and high flowability; and 2, part of low-molecular-weight branched polyamide can be produced in the system and the viscosity of the melt in the system can be reduced due to the amide exchange and branching reaction in the melt extrusion process, and thus, the surface of the product is smooth, and the product can be used in place of metal and is very suitable for shell materials of electronic consumer equipment and automobile parts.

Description

technical field [0001] The invention relates to a reinforced polyamide composition with high filling and good surface. Background technique [0002] Polyamide resin has excellent mechanical strength, heat resistance, chemical resistance, wear resistance and self-lubrication, and low friction coefficient, and is widely used in the fields of electronic appliances, automobiles, furniture, building materials and fibers. Reinforced semi-aromatic polyamide materials have good mechanical properties and high heat distortion temperature, and are expected to replace metals in many applications, mainly through high-filling and reinforced molding materials, especially high-glass Molding compound with reinforced fiber content. However, materials with high glass fiber content will inevitably lead to poor fluidity of the material. It is difficult to inject smoothly in some thin-walled and larger parts, and the surface of the injection molding is very serious. [0003] European patent EP ...

AI Technical Summary

Problems solved by technology

However, since the prepolymer has a high concentration of end groups, there will inevitably be subsequent reactions in the later processing process, which will reduce the fluidity.

Chinese patent CN 1368994A discloses a method of melting and mixing high molecular weight polyamide and polyamide oligomer having a higher melting point than the high molecular weight polyamide at a melt temperature equal to or lower than the melting point of the polyamide oligomer To improve the fluidity of high molecular weight polyamide composition, but this method has its limitations, it can only be effective in some specific resin combinations, and in other systems, it will appear oligomerization at the processing temperature of high molecular weight matrix resin The material is poorly plasticized or even does not melt, for example, it will occur in a system that uses PA66 oligomers to improve the fluidity of high molecular weight PA6 materials

Chinese patent CN 101193982B discloses that linear or branched polyamide oligomers with a number average molar mass of 800-5000 g / mol can effectively improve the processing performance and surface quality of high molecular weight polyamide materials, but require a separate Steps for end group modulation of polyamide oligomers, thus limiting their large-scale use

However, the current production technology with a flat ratio of glass fiber cross-sectional area greater than 2 is expensive, which greatly limits the application of this method

[0004] The improvement of other flow properties is generally achieved by adding flow improvers, the main examples are low molecular weight polyesters (DE 4127720A), polyolefin waxes modified with polar chains (BE 820472A) or salts of magnesium, zinc and aluminum (WO 97 / 19131) or monovalent or divalent metal salts of aliphatic carboxylic acids (CN 1470565A, CN 1230467C), but its disadvantage is that the mechanical properties are greatly reduced while the fluidity is improved, and the substitution The meaning of metal parts