JPH0352492B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to polyolefin compositions having a high degree of flame retardancy. Since polyolefins are composed of hydrocarbons, they have the disadvantage of being easily ignited and combustible, and for this reason, various proposals have been made to make polyolefins flame retardant. In recent years, there has been a tendency for polyolefins used in electrical products, building materials, etc. to be required to have an increasingly high degree of flame retardancy. For example, in the US UL standard,
Parts of electrical products such as the outer frames of televisions were previously allowed to have a flame retardancy of V-2, but now they are required to have a higher flame retardancy of V-1 to V-0. Therefore, products exported to the United States must have a flame retardancy of V-1 to V-0, and naturally a higher degree of flame retardancy is required in our country as well. In this background, various attempts have been made to use organic flame retardants and inorganic flame retardants. Organic flame retardants generally have self-extinguishing properties compared to polyolefins, but they have the disadvantage of causing firedrops when burned. In this regard, inorganic flame retardants do not cause firedrops and have some degree of self-extinguishing properties, but when trying to impart a high degree of flame retardant effect such as V-1 to V-0, extremely large amounts of flame retardants, such as 300 parts by weight must be added to 100 parts by weight of polyolefin. Generally 200 parts per 100 parts by weight of polyolefin
The composition up to the weight part is the rigidity of the molded product,
It is preferable because it improves dimensional stability etc.
If the amount is as large as 300 parts by weight, pelletizing becomes extremely difficult and impractical. That is,
When molded, the fluidity in the molding machine and mold is reduced, and when molded, the impact strength is reduced. The present inventors have found that pelletizing is not difficult;
Moreover, as a result of various studies to develop a polyolefin composition with high flame retardancy equivalent to V-1 to V-0, we found that by using an inorganic ammonium salt in combination with a specific organic flame retardant and antimony trioxide. It was discovered that satisfactory results could be obtained, and the present invention was completed. In the present invention, based on 100 parts by weight of polyolefin,
This is a flame-retardant polyolefin composition containing 35 to 90 parts by weight of an inorganic ammonium salt, 15 to 45 parts by weight of an aliphatic bromine compound having a triazine ring, and 5 to 20 parts by weight of antimony trioxide. Examples of the polyolefin used in the present invention include homopolymers of α-olefins such as ethylene, propylene, and butylene, copolymers of the α-olefins with other α-olefins, block copolymers, and mixtures thereof. In particular, polyolefin containing polypropylene as a main component is preferably used. Further, as the inorganic ammonium salt, any known salt can be used, such as ammonium chloride, ammonium bromide, ammonium sulfate, ammonium phosphate, and ammonium carbonate, among others,
Ammonium chloride, ammonium sulfate or ammonium bromide are preferably used. For these inorganic ammonium salts, by using fine powders with a particle size of 0.1 to 50 μ and a specific surface area of 30 m ² /g or less, it is possible to improve impact resistance and mold with a good surface condition without silver streaks. You can get the goods. Further, it is preferable to surface-treat the inorganic ammonium salt in advance with a surfactant such as sodium stearate or sodium lauryl sulfonate, since this can improve the dispersibility and fluidity of the polyolefin. The amount of inorganic ammonium salt blended in the present invention is 35 to 90 parts by weight per 100 parts by weight of polyolefin.
Preferably it is 40 to 85 parts by weight. If the amount of inorganic ammonium salt blended is less than the above 35 parts by weight, sufficient sagging prevention effect cannot be exhibited, and even if it is greater than the above 90 parts by weight, the effect is limited, and it is rather difficult to produce polyolefin molded products. , it is difficult to knead and pelletize in an extruder, so it is not industrially suitable. The main feature of the present invention is that an aliphatic bromine compound having a triazine ring and antimony trioxide are used in combination with an inorganic ammonium salt. An aliphatic bromine compound having a triazine ring is a compound in which a brominated aliphatic group is bonded to carbon or nitrogen of the triazine ring via an ether bond, an ester bond, an amide bond, etc., or directly.
For example, brominated alkyl cyanurates such as tris(dibromopropyl) cyanurate, bis(dibromopropyl) cyanurate, tris(tetrabromopentyl) cyanurate, bis(tetrabromopentyl) cyanurate; tris(dibromopropyl)thiocyanurate, bis( Brominated alkyl thiocyanurates such as dibromopropyl) thiocyanurate, tris(tetrabromopentyl)thiocyanurate, bis(tetrabromopentyl)thiocyanurate; brominated tris(dibromopropyl)isocyanurate, bis(dibromopropyl)isocyanurate, etc. Examples include alkyl isocyanurates. Among these, compounds having a bromine content of 55% or more are particularly preferably used. In the present invention, it is extremely important to use a particularly selected aliphatic bromine compound having a triazine ring among aliphatic bromine compounds known as flame retardants. That is, compounds that do not have a triazine ring even if they are aliphatic bromine compounds, such as tetrabromide bisphenol A bis (dibromide propyl ether), tetrabromide dihydroxy, diphenyl sulfone (dibromide propyl ether), tetrabromide Bromobutane, tribromopropane, etc. cause fire dripping and cannot be applied to the present invention. The amount of the aliphatic bromine compound having a triazine ring in the present invention is 15 to 45 parts by weight, preferably 20 to 40 parts by weight, based on 100 parts by weight of the polyolefin. If the amount of this bromine compound is less than 15 parts by weight, the self-extinguishing property will be insufficient, and if it is more than 45 parts by weight, the thermal decomposition effect will be strong and foaming, decomposition and discoloration will easily occur. , and also makes extrusion difficult, which is not preferable. In addition, polyolefin
When blending 40 to 85 parts by weight of an inorganic ammonium salt with respect to 100 parts by weight, a higher degree of flame retardancy is imparted by increasing the amount of the bromine compound to 30% by weight or more based on the inorganic ammonium salt. preferred for. Furthermore, antimony trioxide is 5 to 20 parts by weight, especially 9 to 16 parts by weight, based on 100 parts by weight of polyolefin.
It is preferable to add 1 part by weight in order to impart a higher degree of flame retardancy. In the present invention, the mixing order of polyolefin, inorganic ammonium salt, aliphatic bromine compound having a triazine ring, and further antimony trioxide is not particularly limited, and each component may be mixed simultaneously, or several components may be mixed in advance and the remaining may be mixed later. The mixing method is also not particularly limited, and is generally carried out using a tumbler blender, a V-type blender, a Henschel mixer, a ribbon mixer, or the like.
Furthermore, several types were mixed in advance with a Henschel mixer,
It is also possible to adopt a method of changing the mixing order and device, such as adding the remaining ingredients and mixing in a tumbler blender. Further, the extrusion method is not particularly limited either, and the composition of the present invention mixed in a predetermined ratio may be extruded and pelletized at once, or some components may be mixed and pelletized in advance, and then the remaining components may be mixed to achieve the desired ratio of the predetermined ratio. A composition may be obtained. The polyolefin composition in the present invention basically consists of the polyolefin, an inorganic ammonium salt, an aliphatic bromine compound having a triazine ring, and antimony trioxide, but in addition to these components, conventionally known stabilizers, Coloring agents, antistatic agents, lubricants, nucleating agents, various fillers, glasses, various coupling agents, etc. may be added. The polyolefin composition of the present invention has an extremely high degree of flame retardancy, and has a V-
It is also possible to have a high degree of flame retardancy, corresponding to V-1 to V-0. The reason why such flame retardancy is obtained is not clear, but it is thought that aliphatic bromine and nitrogen in the triazine ring interact with inorganic ammonium salt and antimony trioxide to exhibit high flame retardancy. I'm guessing. Furthermore, the amount of inorganic ammonium salt is 35% per 100 parts by weight of polyolefin.
Since it contains up to 90 parts by weight, it has the advantage of good dimensional stability and high rigidity when molded. EXAMPLES In order to explain the present invention more specifically, Examples and Comparative Examples will be described below, but the present invention is not limited to these Examples. The experimental results shown in Examples and Comparative Examples were conducted in accordance with the vertical method of the UL94 standard, and the average self-extinguishing time was
The average self-extinguishing time after flaming each of the 10 combustion test pieces twice, ie, 20 times in total, is shown. Furthermore, the maximum autolysis time was the maximum value among the autolysis times after the 20 times of inflammation. The extent to which the cotton under the test piece ignited due to "flame" from the test piece was expressed by how many out of 10 cotton strands were ignited. For example, if 3 out of 10 lights were ignited, it would be displayed as 3/10. The shape of the test piece is 5 inches x 0.5 inches x 1/1
I went with 6 inches. Example 1 An inorganic ammonium salt, an aliphatic bromine compound having a triazine ring, and an aliphatic bromine compound having a triazine ring in the proportions shown in Table 1 based on 100 parts by weight of polypropylene (ME240 manufactured by Tokuyama Soda Co., Ltd.)
Antimony trioxide and a heat stabilizer were mixed using a super mixer (manufactured by Kawada Seisakusho). The heat stabilizers include 2,6-di-tert-butyl-4-methylphenol, dilaurylthiopropionate, and calcium stearate, each containing 0.1% of the total composition.
It was added at a concentration of 0.2% and 0.1%. Then,
Using an extruder with a kneader (manufactured by Nakatani Kikai Co., Ltd.),
The mixture was melt-kneaded and pelletized. This pellet
A test piece was obtained by molding using a 1.5oz injection molding machine (manufactured by Kawaguchi Churchill Co., Ltd.). Using this test piece, a combustion test (UL standard SB94 vertical method) was conducted, and the average and maximum values of self-extinguishing time and cotton ignition rate were measured, and these values are also listed in Table 1.

[Table] * corresponds to a comparative example.
Comparative Example 1 Test pieces were prepared in the same manner as in Experiment No. 6 of Example 1, except that the amounts of ammonium chloride, tris(dibromopropyl) isocyanurate, and antimony trioxide were changed as shown in Table 2. It was created. A test similar to that in Example 1 was conducted using the obtained test piece. The results are also listed in Table 2.

【table】

Claims (1)

[Scope of Claims] 1. A compound comprising 100 parts by weight of polyolefin, 35 to 90 parts by weight of an inorganic ammonium salt, 15 to 45 parts by weight of an aliphatic bromine compound having a triazine ring, and 5 to 20 parts by weight of antimony trioxide. Flammable polyolefin composition. 2. The composition according to claim 1, wherein the polyolefin is polypropylene. 3. Claim 1, wherein the inorganic ammonium salt is at least one selected from ammonium chloride, ammonium bromide, and ammonium sulfate.
Compositions as described in Section. 4. The composition according to claim 1, wherein the aliphatic bromine compound having a triazine ring is an ester of isocyanuric acid and a brominated aliphatic alcohol. 5. The composition according to claim 1, wherein the aliphatic bromine compound having a triazine ring is tris(dibromopropyl)isocyanurate.