Low-filling efficient synergistic flame-retardant nylon 66 and preparation method thereof

Abstract

The invention belongs to the technical field of modified nylon materials, and particularly relates to low-filling efficient synergistic flame-retardant nylon 66 and a preparation method thereof. The low-filling efficient synergistic flame-retardant nylon 66 comprises the following components in parts by mass: 88-92 parts of nylon 66; 6.5 to 10 parts of a composite flame retardant; 0.1 to 0.2 part of a dispersant; 0.1 to 0.2 part of an antioxidant; 0.7 to 3 parts of an inorganic nano filler; wherein the composite flame retardant comprises the following components in parts by mass: 2-4 parts of aluminum hypophosphite; 0 to 1 part of hexaphenoxy cyclotriphosphazene; 1 to 3 parts of aluminum diethyl hypophosphite; 0-2 parts of ammonium polyphosphate; 0 to 3.5 parts of nano aluminum hydroxide; and 0-2 parts of magnesium oxide. The inorganic nano filler comprises nano silicon dioxide with the particle size of 10-50nm, montmorillonite and nano aluminum oxide. The flame-retardant nylon 66 at least comprises one or more of the composite flame retardant and the inorganic nano filler, when the adding amount of the composite flame retardant is 10% or below, the flame-retardant level of the prepared flame-retardant nylon 66 can reach the UL94 V-0 level, and the tensile strength and the impact strength of the prepared flame-retardant nylon 66 are greatly improved.

Description

technical field [0001] The invention belongs to the technical field of modified nylon materials, and in particular relates to a low-filling high-efficiency synergistic flame-retardant nylon 66 and a preparation method thereof. Background technique [0002] PA66 (polyamide 66) has been widely used in electronics, transportation, aerospace and other industries due to its excellent physical properties, chemical properties and processing properties. However, due to the poor flame retardancy of PA66, such as the limiting oxygen index of 24.0%, and the UL94 vertical combustion rating of V-2, it is a flammable material, which limits its use in special environments (such as high temperature). [0003] Patent CN105111735A discloses a halogen-free, low-toxic, low-smoke, flame-retardant nylon 66 compound prepared by using melamine cyanurate halogen-free flame retardant and melamine orthophosphate as halogen-free flame retardant. But the notched impact strength of the flame retardant m...

AI Technical Summary

Problems solved by technology

However, because the added red phosphorus changes the color of nylon 66, it can only be used for dark-colored products, which limits its scope of use.

[0005] Patent CN104746168B discloses a kind of flame retardant nylon 66 fiber and its preparation method. The flame retardant PA66 is prepared by the polymerization reaction of aminomethylphenyl hypophosphorous acid, nylon 66 salt and water in the reaction kettle, but by bonding PA66 While branching new groups to achieve flame retardancy, it affects the crystallinity of PA66 itself, causing PA66 to lose its original excellent mechanical properties

[0006] Patent CN102337029B discloses a preparation method of a halogen-free flame-retardant nylon 66 composite material. This method prepares a flame-retardant composite material by melting and blending a flame retardant, a nucleating agent, and glass fibers. Although the flame-retardant performance of the composite material is Good, but the total amount of additives in the composite material is as high as 50%, and its mechanical properties drop greatly

[0007] Patent CN104762688A discloses a flame-retardant nylon 66 polymerized by nylon 66 salt, water and aminomethylphenylphosphinic acid. The flame-retardant nylon 66 of this invention has certain flame retardancy, but it is connected to the PA66 chain. Groups with more branches have a greater impact on the crystallinity of PA66 and have a greater impact on the mechanical properties of PA66

[0008] Patent CN 104211954 A discloses a method of copolymerizing reactive flame retardant DOPO derivatives with dibasic acids or diamines to form salts, and then copolymerizing the salts with nylon 66 salts to obtain halogen-free flame-retardant nylon 66 polymer method, although the composite PA66 prepared by this method has certain flame retardancy, the amount of flame retardant in the reaction kettle of this method needs to be added up to 30%, which has caused a large impact on the mechanical properties of nylon 66. reduce

[0009] As mentioned above, the existing technology discloses a variety of preparation methods of flame-retardant nylon 66, but the mechanical properties of nylon 66 after modification are greatly reduced, especially the toughness loss of nylon 66 is relatively large

In addition, most of the flame retardant effects need to add a large amount of flame retardants, and the amount of flame retardants is more than 30% or even higher.

The addition of flame retardants is too high, which will affect the mechanical properties of nylon 66, or the addition of flame retardants will change the appearance of nylon 66, limiting its use

Images