A polyamide composition resistant to glow wire and non-flammable, its preparation method and application

Abstract

The invention discloses a polyamide composition resistant to glow wire and non-ignition, a preparation method thereof and an application in the field of electronic appliances. In terms of weight percentage, the raw material composition of the polyamide composition includes: 30%-80% of thermoplastic polyamide resin, 5%-20% of microcapsule red phosphorus flame-retardant masterbatch, and 3%-12% of flame-retardant synergist , 10% to 50% of reinforcing components, 0% to 5% of other additives; the mass ratio of microcapsule red phosphorus flame retardant masterbatch to flame retardant synergist is 1 to 5:1; the total weight of raw materials is 100% In total, the flame retardant synergist includes: 1% to 8% of DOPO modified inorganic flame retardant, and 0.5% to 4% of glow wire incombustible additive. The preparation method is to mix all the raw materials except the reinforcing component according to the proportion and then add them to the twin-screw extruder. Cool, dry and cut into pellets.

Description

technical field [0001] The invention relates to the technical field of polymer materials, in particular to a polyamide composition which is resistant to glow wire and does not burn, and its preparation method and application. Background technique [0002] In recent years, due to electric leakage, overload, short circuit, arc and other reasons in the process of using electronic and electrical equipment, local overheating and ignition of plastic materials have caused frequent fires, posing a serious threat to human life and property. As a result, the International Electrotechnical Commission IEC has greatly strengthened the flame retardant standards, especially the resistance of plastic parts used in household appliances with high current (over 0.2 amperes) that are unattended for a long time in the safety standards for household and similar electrical appliances (IEC60335). The flammability requirements are the most stringent, and the most severe third-level flammability eval...

AI Technical Summary

Problems solved by technology

Unfortunately, the red phosphorus composition is poorly reproducible in GWT750 <= 2s glow wire and depends on part geometry

[0004] Chinese patent document CN103492488A (application number 201280020075.5) discloses a flame-retardant polyamide molding composition, which uses red phosphorus and melam chemicals as compound flame retardants to pass the flame-retardant requirements of GWIT775°C , but the poor compatibility between melam chemicals and polyamides greatly reduces the impact performance of the material, which requires a toughening agent to make up for it, increasing the cost

[0005] Chinese patent document CN105121552 A (application number 201480022006.7) discloses a polyamide resistant to glow wire. type, making it resistant to glow wire, although the material can pass GWFI960°C (1.5mm) and UL94 (0.8mm), it fails in the test of glow wire GWT750 total burning time <= 2 seconds, and the dialkyl Phosphate flame retardants are expensive and difficult to promote on a large scale

[0006] Chinese patent document CN107216648 A (application number is 201710628997.9) discloses a flame-retardant polyamide composite material. Salt and magnesium hydroxide or a mixture of silicate) to obtain a flame retardant grade of 0.8mm UL94 V-0 grade, and the glow wire under three thicknesses (3.0mm / 1.5mm / 0.75mm) is ignited The temperature (GWIT) can reach a severe level of 750°C, but the impact performance of the material is insufficient, and it is difficult to meet the application requirements of high-stress snap-connected thin-walled parts

[0007] If the material wants to pass the GWT glow wire test directly, the total burning time at 750 ° C is required to be <= 2 seconds, which actually means that the material is not allowed to have an open flame during the entire 60s of the glow wire test, so it is more non-ignitable than the glow wire (GWIT, 775°C) requirements have been greatly increased, and red phosphorus itself is flammable when exposed to open flames, which seriously restricts the cost-effective advantages of red phosphorus-based polyamide compositions and their application in the field of electronic appliances

Images