KR930002002B1 - Polyamide resin composition - Google Patents

Abstract

The fire reardant polyamide resin composition is prepared by adding, at a time, 5-20 wt.% of 9,10- dihydro-9-oxo-10-phosphapeneantrene-10-melamine and 1-5 wt.% of polyvinylidene difluoride to 75-94 wt.% of the polyamide resin. The obtd. polyamide resin compsn. has excellent moldability and anti- arctracking property. The process prevents corrosion of the mold and machine. The obtd. polyamide resin composition has good thermal properties and electrical properties.

Description

Composition of Flame Retardant Polyamide Resin

The present invention relates to a composition of a flame retardant polyamide resin, and more particularly to 9,10-dihydro-9-oxo-10-phosphaphenanthrene-10-melamine and polyvinylidene difluoride in a polyamide resin. Both thermal and electrical properties added at the same time relate to good flame retardant polyamide resin compositions.

Conventionally, in order to impart flame retardancy to a polyamide resin, a method of adding a flame retardant, for example, a halogen-containing compound, a mixture of metal oxides, a nitrogen-containing compound, a phosphorus-containing compound, and the like to a polyamide resin has been mainly used. In the case of use, since the intrinsic physical properties of the polyamide resin change, the flame retardant had to be selected appropriately according to the physical properties. In other words, when the halogen-containing compound and the metal oxide compound are used as the flame retardant, an excessive amount of the flame retardant must be added, resulting in deterioration of processability and mechanical properties, as well as the generation of toxic gases, which corrode molds and molding equipment. In addition, in the case of using a nitrogen-containing compound, when the compound is used between the flame retardant and the fiber used, there is a small amount of compatibility and affinity between the flame retardant and the fiber used. Due to the lack of heat resistance, there was a problem that the surface state of the molded product was not good, and even when using a phosphorus-containing compound as a flame retardant, a toxic gas was also generated to corrode the mold and the molding machine, and red phosphorus was used as a flame retardant. In case of fire, low flash point There was a disadvantage, and the color of the molding was also a disadvantage.

On the other hand, U.S. Patent No. 3,660,344 describes that melamine, which is a nitrogen-containing compound, is used as a flame retardant. However, in this case, it is excellent in flame retardancy but poor in compatibility and affinity with the resin, so that it is evenly dispersed in the resin. It is difficult, and mold injection is a phenomenon in which a flame retardant precipitates in a mold during injection molding, and a blooming phenomenon occurs due to the sublimability of melamine.

In addition, U.S. Patent No. 3,980,616 describes a method of using cyanuric acid as a flame retardant, but this method has improved the flame retardancy and blooming phenomenon than the case of using the melamine described above as a flame retardant. , Because cyanuric acid used as a flame retardant is weak and unstable to heat, foaming occurs on the surface of the molded article. In addition, Japanese Patent Publication No. 56-106, 955 describes the use of cyanuric acid melamine as a flame retardant, although some of the above problems have been improved. There was a drawback that the silver surface phenomenon occurred on the surface of the molded article when it rose, and the color change occurred, and the affinity between the flame retardant and the resin was not good, and the mechanical properties of the final product were greatly reduced.

In order to solve the problems of the prior art, the present invention solves the state of the molded product during the manufacturing process or the molding process of the flame retardant polyamide resin composition, the corrosion of the mold and the molding machine, and especially the flame retardant polyamide resin having excellent arc tracking resistance. The purpose is to provide a composition.

Hereinafter, the present invention will be described in detail.

In the polyamide resin composition, polyamide resin melamine and 9, 10-dihydro-9-oxo-10-phosphaphenanthrene-10-chloride and 75 to 94% by weight relative to the total resin amount and 5 to 20% by weight of 9, 10-dihydro-9-oxo-10-phosphaphenanthrene-10-melamine, a compound synthesized by reacting the derivative in a molar ratio of 1: 1 to 1: 6, polyvinylidene It is a flame-retardant polyamide resin composition characterized by adding 1-5 weight% of difluorides simultaneously.

Hereinafter, the present invention will be described in more detail.

The present invention relates to 9, 10-dihydro-9-oxo-10- synthesized by reacting melamine with 9, 10-dihydro-9-oxo-10-phosphaphenanthrene-10-chloride (hereinafter referred to as DOPC). A polyvinylidene difluoride (hereinafter referred to as PVPE) obtained by polymerizing phosphaprene anthren-10-melamine (hereinafter referred to as DOPM) and vinylidene fluoride (hereinafter referred to as PVPE) is a composition obtained by simultaneously adding a polyamide resin. In the description of the properties and functions, 9,10-dihydro-9-oxo-10-phosphaphenanthrene-10-melamine is a compound containing phosphorus and nitrogen, which is caused by incombustible gas generation and Non-combustible bullets are produced, resulting in synergistic effects and mutually flame retardant effect. However, this flame retardant has an effect of facilitating accumulation and the resulting carbide forms a conductive path, which results in a slight lack of arc-tracking resistance (capacity of polymer carbide at discharge). At this time, the added PVDF is non-flammable by itself, and exhibits a central effect of raising the melt viscosity of the polyamide resin while preventing dripping and preventing the generation of conductive length.

DOPM used in this flame retardant polyamide resin composition has an average particle diameter of 5 to 10 mu, a phosphorus content of 10 to 20% by weight, and PVDF has an average molecular weight of 30,000 to 80,000, a melting point of 160 to 180 ° C, and a melt viscosity of 210 to It is about 2,000 to 10,000 poise at 270 degreeC.

Meanwhile, in the present invention, polyamide resins include nylon 6, nylon 66, nylon 6/66, nylon 6,10, nylon 6,12, nylon 11, nylon 12, nylon 46, and the like. In order to make the flame retardancy of the composition correspond to the V0 standard of ULSubject 94, the amount of DOPM added to the polyamide resin is preferably about 5 to 20% by weight of the total resin amount. When 20 weight% or more is added, coloring power becomes high and coloring becomes difficult, melt flow property falls and workability becomes poor. In addition, the amount of PVDF is preferably about 1 to 5% by weight of the total resin amount. If less than 1% by weight is added, the inherent effect of preventing dropping and improving arc-tracking resistance is insignificant. Phase separation with the resin occurs and various physical properties deteriorate.

In the present invention, when the DOPM and PVDF are added to the polyamide resin at the same time, a special method is not used, and a method of adding the polyamide resin and the DOPM in the form of molten polyamide powder or pallet and then dispersing them is used. It is preferable to mix PVDF to make a molding chip through a kneading extruder and then injection molding it.

Unlike the conventional resin composition, the flame retardant polyamide resin composition according to the present invention is excellent in flame retardancy and thermal properties and especially arc carbonization resistance, and thus may be usefully used as an insulating material for electric and electronic products.

Hereinafter, the present invention will be described in more detail with reference to Examples. Evaluation methods relating to the Examples and Comparative Examples of the present invention are as follows.

1) Evaluation method of flame retardancy

It was carried out according to the combustion test method specified in UL Subject 94 STANDARD.

2) Blooming phenomenon occurs and how to judge

A disc-shaped specimen having a thickness of 3.2 mm and a diameter of 100 mm was prepared and treated under a hot air oven at 150 ° C. for 100 hours, and then treated at 95 ° C. and 90% relative humidity for 200 hours to observe the surface state of the specimen. It judged by.

3) Evaluation method of mechanical and electrical properties

Using injection molded specimens, the tensile strength was ASTM D-638, the impact strength was ASTM D-256, and the arc resistance was according to the standard of ASTM D-495.

[Examples 1 to 6 and Comparative Examples 1 to 7]

The molding chip was prepared by kneading and extruding a medium-weight nylon 6 chip for general molding and an additive of a composition ratio as shown in Table I below in a melt kneading extruder maintained at a cylinder temperature of 230 to 250 ° C. The chip was dried to prepare the evaluation test specimen using an injection molding machine maintained at a cylinder temperature of 235 to 250 ° C. The results are shown in Table II.

TABLE 1

TABLE 2

V0: Best, V2: Normal

As can be seen from the results of Table II, the flame retardant polyamide resin composition according to the present invention was much better in flame retardancy, thermal properties and arc resistance than the conventional resin composition.

Claims (1)

In the polyamide resin composition, 5 to 20% by weight of 9, 10-dihydro-9-oxo-10-phosphaphen anthrene-10-melamine in a polyamide resin corresponding to 75 to 94% by weight relative to the total resin amount A flame retardant polyamide resin composition characterized by adding at the same time 1 to 5% by weight of polyvinylidene difluoride.